Prolene hernia system versus Lichtenstein repair for inguinal hernia: a meta-analysis

Abstract

Background

Lichtenstein repair is standard practice for inguinal herniorrhaphy, but there is increasing public concern in the use of mesh and postoperative chronic pain. New mesh technology, such as the prolene hernia system, has a preperitoneal component to reinforce the myopectineal orifice aim to reduce the risk of recurrence and chronic pain. This meta-analysis compares outcomes using prolene hernia system versus lichenstein repair for inguinal hernias.

Methods

Randomized-controlled trials comparing prolene hernia system and Lichtenstein repair were identified using Embase, Medline, and published conference abstracts. Primary outcomes were recurrence and chronic pain. Secondary outcomes were mean operating time, composite complications, surgical reintervention, and time to normal activities. Odds ration and standardized mean differences were calculated.

Results

1377 hernia repairs were identified from a total of 7 trials. Mean follow-up was 12–91 months. There was no difference between the techniques for recurrence [pooled analysis odds ratio: 0.86 (95% CI 0.32–2.28); p = 0.76] and chronic pain [pooled analysis odds ratio: 1.00 (95% CIs 0.65–1.55); p = 1]. Prolene hernia system demonstrated a shorter time to return to normal activities [pooled weighted mean difference − 0.54 (95% CI − 1.07 to − 0.01); p = 0.04]. Other outcomes were similar in mean operating time, composite complications, and surgical reintervention.

Conclusion

Both prolene hernia system and Lichenstein repair appear comparable acceptable techniques for inguinal herniorrhaphy. Further longer-term studies of new mesh technologies will improve information available to surgeons and their patients.

http://bit.ly/2TUiouY

Robotic retromuscular ventral hernia repair and transversus abdominis release: short-term outcomes and risk factors associated with perioperative complications

Abstract

Background

Retromuscular ventral hernia repairs have become increasingly popular, both with and without transversus abdominis release. We aim to describe our 90-day outcomes in patients who underwent robotic retromuscular ventral hernia repair (RRVHR).

Methods

All patients were subcategorized into those who underwent a TAR (TAR+) as part of their repair, and those who did not (TAR−). Patient demographics, comorbidities, hernia characteristics, and LOS were studied. Perioperative complications were reviewed in four different time frames up to 90 days. All hernias and complications were classified using the recommended classification systems. Appropriate univariate analyses and multivariate regression analyses were performed to determine the hernia characteristics which required a TAR technique, and risk factors which associated with the development of complications.

Results

Of 454 robotic ventral hernia repairs, 101 patients who underwent RRVHR were included into the study. Of these, 54 patients underwent RRVHR with TAR while the remaining 47 patients underwent repair without TAR. Incisional hernias, off-midline locations, and larger size defects were factors that required the addition of a TAR. In 9.9% patients, an unplanned TAR was performed. Postoperative pain assessment was similar in both groups. LOS was significantly longer for TAR + group (p < 0.001). The median Comprehension Complication Index^® score was 8.7 (range: 0–42.4) for all patients and was significantly higher for TAR+ group (p = 0.014). Complications were higher in the TAR+ group as compared to the TAR− group (p = 0.028), though this difference did not persist in follow-up. Most complications were minor (Clavien–Dindo grade-I and -II). The development of complications was only associated with the presence of an incarcerated hernia at repair.

Conclusion

RRVHR is safe and feasible. 9.9% of our cohort required a TAR that was unplanned, particularly incisional hernias. TAR patients may be more prone to complications in the immediate post-operative period, however, the difference between patients with and without TAR adjuncts resolved at 90 days.

http://bit.ly/2BzyBhR

Risk factors and control of seizures in 778 Chinese patients undergoing initial resection of supratentorial meningiomas

Abstract

This retrospective study explored the risk factors for the occurrence of seizures in the pre- and postoperative period in patients undergoing supratentorial meningiomas surgery to investigate those who are likely to benefit from prophylactic antiepileptic drugs (AEDs). We reviewed the medical records of 778 supratentorial meningiomas patients who were operated at our institution between 2011 and 2012. A total of 100 (12.9%) patients experienced preoperative seizures; 41 patients (5.3%) experienced postoperative in-hospital seizures, and 91 (13.5%, n = 673) patients experienced postoperative seizures after discharge. Multivariate analysis revealed that motor cortex involvement (odds ratio [OR] 3.243, P < 0.001) and peritumoral edema ≥ 1 cm (OR 3.936, P < 0.001) were significant risk factors of preoperative seizures. Whereas presenting with headache (OR 0.259, P < 0.001) and age ≥ 55 years at surgery (OR 0.514, P = 0.009) showed decreased incidence of preoperative seizures. The involvement of motor cortex (OR 3.290, P = 0.003), postoperative Karnofsky Performance Scale (KPS) ≤ 70 (OR 5.389, P < 0.001), preoperative seizure (OR 4.003, P < 0.001), and occurrence of any medical/surgical complication (OR 3.925, P = 0.001) were significant risk factors for postoperative in-hospital seizures. Postoperative seizures after discharge were associated with tumor maximal diameter ≥ 3.5 cm (OR 1.903, P = 0.022), preoperative seizures (OR 4.350, P < 0.001), postoperative in-hospital seizures (OR 6.385, P < 0.001), and tumor recurrence/progression (OR 7.642, P < 0.001). The probability of seizure freedom in the 5-year follow-up was roughly 59% among patients with preoperative seizures, and 87% among patients without preoperative seizures. Cox regression analysis showed that tumor recurrence/progression (relative risk 2.987, 95% CI 1.517, 5.879, P = 0.002) was the only predictor of postoperative seizures in patients without a history of preoperative epilepsy. The use of postoperative prophylactic antiepileptic drug (AED) did not reduce the incidence of seizures in our analysis. Understanding the risk factors for seizures might help clinicians to predict their occurrence and develop effective anti-epileptic treatment strategies. Further prospective randomized controlled trials are needed to determine the risk factors for seizures and the efficacy of AED prophylaxis.

http://bit.ly/2TSgLxU

Fractal study on Saraswati supercluster

Abstract

The study of galaxies and superclusters is a major field of interest of astrophysicists. With the development of modern advanced telescopes and data acquisition systems, scientists could gather more information about the universe. Investigations using Sloan 2.5-m telescope, the multi-fiber spectrograph and the galaxy redshift data recorded enabled the discovery of Saraswati—an extremely massive and giant supercluster. Fractal analysis is an established powerful mathematical technique for the analysis and study of complex systems extending from microcosm to macrocosm. Fractal dimension is related to the complexity of the system. In the present work, an attempt has been made to analyze the recently reported supercluster Saraswati by box-counting method. It is found that fractal dimension is very high for the supercluster and low for the voids. The fractal dimension of 1.75–2 in the Saraswati region suggests a sheet-like morphology to it. Complexity mapping is carried out by plotting contour plot of fractal dimension and percentage occupancy plot, which enable greater understanding of the distribution of galaxies in the universe.

http://bit.ly/2DEvm96

Features of horizontal magnetic field intensity over northern island of Malaysia

Abstract

This study utilized magnetic field records of the horizontal component obtained from magnetic data acquisition system at northern island of Malaysia to delineate the diurnal variations of SqH and their monthly mean MSqH for a period of 4 years. The results show that for the entire period of study, the daytime SqH amplitudes increase from \(\sim 20\) to \(\sim 160\)  nT and their MSqH amplitudes increased from \(\sim 40\) to about 135 nT in 2008 to 2013, respectively. These variabilities of SqH and MSqH reached peak amplitudes between 10:00 and 12:00 LT hrs. The standard deviation fairly responds to the daily variability of SqH with a phase shift in January 2008 and 2013 which may likely have connection to the sudden stratospheric warming event that occurred in these months. We observed the extension of eastward field that continued beyond the sunset (18:00 LT) hours is more prevalent with higher magnitudes during the deep minimum solar activity and the probable causes are discussed. The observed counter equatorial electrojet associated with late reversal of night-time westward electric field (WEF) shows inverse relationship with increasing solar activity and those that are not associated to late reversal of night-time WEF seems to indicate linear relationship exception of deep minimum solar activity year (2008). We also observed a gradual shift of ECEJ to the morning sector with increasing solar activity. Throughout the years, days with stronger morning counter equatorial electrojet magnitudes generally weaken the expected strong eastward current and shifted its peak to earlier local time. The annual and seasonal variations of SqH show semiannual variation with equinoctial maxima and solstitial minima. About 40% of the SqH shows positive night-time to pre-sunrise variations which suggest the existence of weak electric currents not necessarily of ionospheric origin with appreciable influence at this longitude sector. The extension of eastward field beyond the sunset hours suggests likely modification of the evening side ionosphere over this region.

http://bit.ly/2SDULdB

Neck Injuries: a Complex Problem in the Deployed Environment

Abstract

Purpose of Review

Evaluation and treatment of injuries to the neck has received a lot of attention over the past 20 years. New evaluation protocols and treatment recommendations have been developed. The goal of this review is to examine these strategies and evaluate their suitability for treatment of patients in a deployed setting.

Recent Findings

Studies from several large trauma centers have changed common practice with regard to both penetrating and blunt neck injuries. The requirement to explore all zone II neck injuries has largely been replaced by a selective exploration based on physical examination and imaging. Also, blunt cerebrovascular injuries, once thought to be rare, have been demonstrated to be common and treatment dramatically reduces the morbidity and mortality.

Summary

Injuries to the neck are a significant problem in the deployed environment. The blast injuries that are common in Iraq and Afghanistan produce multiple injured casualties. In addition to injuries to other body regions, injuries to the neck can involve both blunt and penetrating mechanisms as well as injuries to the spinal column. The extent and outcome of these complex injuries has not been fully evaluated and would remain an area worthy of study.

http://bit.ly/2Ed94Nq

Three-stage laparoscopic surgery in a morbidly obese patient with Hinchey III diverticulitis: a case report

Abstract

Background

Perforated diverticulitis with purulent peritonitis (Hinchey III diverticulitis) has traditionally been treated with a Hartmann's procedure in order to avoid the considerable postoperative morbidity and mortality associated with one-stage resection and primary anastomosis. Although there have been reports regarding laparoscopic lavage as the initial treatment of perforated Hinchey III diverticulitis, a formal treatment strategy has not been established yet. We performed a three-stage surgery, including laparoscopic lavage and drainage with diverting ileostomy (first stage), laparoscopic sigmoidectomy (second stage), and ileostomy closure (third stage) in a morbidly obese patient with Hinchey III diverticulitis.

Case presentation

A 31-year-old man who presented with abdominal pain was diagnosed with perforated diverticulitis and sent to our hospital for evaluation. He had morbid obesity (body mass index (BMI) 50 kg/m²), acute renal failure, and uncontrolled diabetes. We performed an emergency operation including laparoscopic lavage and drainage with a diverting ileostomy for this case of Hinchey III diverticulitis. Fifteen months after the first-stage surgery, we performed laparoscopic sigmoidectomy as the second stage. Finally, 5 months later, we performed ileostomy closure. The patient recovered without significant complications.

Conclusion

Three-stage surgery including early laparoscopic lavage and proximal diversion for morbidly obese, comorbid patients with Hinchey III diverticulitis may be indicated in the acute phase to avoid perioperative complications and permanent colostomy creation.

http://bit.ly/2V6lqg1

Esophageal metastasis of breast cancer during endocrine therapy for pleural dissemination 21 years after breast surgery: a case report

Abstract

Background

The esophageal metastasis of breast cancer is rare. Moreover, it is extremely unusual for patients to experience the symptoms of esophageal metastasis during their lifetimes. We present a case of dysphagia caused by esophageal metastasis after a long interval following a primary mastectomy.

Case presentation

A 77-year-old woman with a history of heterochronous bilateral breast cancer and under treatment for pleural dissemination recurrence originating from right breast cancer complained of dysphagia. At the age of 56, she had undergone a right radical mastectomy for right breast cancer. The histopathological findings revealed invasive ductal carcinoma, pT3N1M0, which was estrogen receptor (ER)- and progesterone receptor (PgR)-positive. At the age of 73, she underwent a second operation, a left modified radical mastectomy. The histopathological examination revealed invasive ductal carcinoma, pT1N0M0, which was negative for ER, PgR, and human epidermal growth factor receptor 2 (HER2). Four years after completion of adjuvant therapy for the left breast cancer, pleural effusion on her left side was observed and histopathological examination of a sample revealed pleural dissemination resulting from the right breast cancer. After initiation of therapy for recurrence, she developed dysphagia and, therefore, underwent an upper gastrointestinal tract endoscopic examination. The examination revealed whole circumferential stenosis and a band unstained by Lugol's solution located 30 cm from her incisors. Examination of a biopsy specimen revealed a subepithelial luminal structure and dysplastic cells. Immunostaining was positive for CK7 and negative for CK20; furthermore, the sample was ER and PgR-positive. Considering the pathological findings, the patient was diagnosed with esophageal metastasis of her right breast cancer.

Conclusions

Metastatic lesions in the esophagus are often located in the submucosa; therefore, they may not be definitively diagnosed by histopathological examination of mucosal biopsy specimens. Esophageal metastasis originating from breast cancer often occurs as a part of multiple organ metastases; however, esophageal metastasis is usually not considered a prognostic factor for patients. Therefore, treatment should be determined according to the severity of the other metastatic sites and the degree of esophageal stenosis.

http://bit.ly/2EcWXQq

Non-occlusive intestinal ischemia in the ascending colon and rectum: a pediatric case occurring during encephalitis treatment

Abstract

Background

Non-occlusive mesenteric ischemia (NOMI) is a rare and severe pathological condition that can cause intestinal necrosis without mechanical obstruction of the mesenteric artery. NOMI often develops during the treatment of severe disease in elderly patients and mostly occurs in the intestine supplied by the superior mesenteric artery (SMA). We experienced a 12-year-old patient with NOMI that was segmentally localized in the ascending colon and rectum during encephalitis treatment.

Case presentation

A 12-year-old boy was hospitalized with limbic encephalitis. On day 41 after admission, he abruptly developed hypotension following diarrhea and fever, and presented abdominal distension. A computed tomography scan revealed pneumatosis intestinalis localized in the ascending colon and rectum coexisting with portal venous gas. The presence of peritoneal signs required an emergency laparotomy. Intraoperatively, skip ischemic lesions were found in the ascending colon and the rectum without bowel perforation. SMA and superior rectal arterial pulsation were present, and the patient was diagnosed with NOMI. The remaining colon, from the transverse to the sigmoid colon, appeared intact. We performed a distal ileostomy without bowel resection. Postoperative colonoscopies were carried out and revealed rectal and ascending colon stenosis with ulceration but demonstrated the patency of the two lesions. We confirmed the improvement of the transient bowel strictures; therefore, the ileal stoma was closed 14 months after the previous laparotomy.

Conclusion

NOMI can be present in childhood during encephalitis treatment and can be segmentally localized in the ascending colon and the rectum. Although NOMI is most often seen in elderly patients, we should also consider the possibility of NOMI when pediatric patients with severe illness manifest abdominal symptoms.

http://bit.ly/2V0egtt

Beyond the conventional collisional absorption of laser light in under-dense plasma: A particle-in-cell simulation study

Abstract

Collisional absorption of laser light in an under-dense plasma is studied by particle-in-cell (PIC) simulation with Monte Carlo binary Coulomb collisions between charge particles. For a given plasma thickness of a few times the wavelength of 800 nm laser, fractional absorption ( \(\alpha \) ) of the laser light due to Coulomb collisions (mainly between electrons and ions) is calculated at different electron temperature \(T_\mathrm {e}\) with a total velocity \(v = ({ v}_\mathrm {th}^2 + { v}_0^2/2)^{1/2}\) dependent Coulomb logarithm \(\ln \Lambda (v)\) , where \({ v}_\mathrm {th}\) and \({ v}_0\) are thermal and ponderomotive velocity of an electron. In the low-temperature regime ( \(T_\mathrm {e}\lesssim 15\)  eV), it is found that \(\alpha \) increases with increasing laser intensity \(I_0\) up to a maximum corresponding to an intensity \(I_c\) , and then it drops (approximately) obeying the conventional scaling of \(\alpha \propto I_0^{-3/2}\) when \(I_0>I_c\) . Such a non-conventional increase of \(\alpha \) with \(I_0\) in the low-intensity regime was demonstrated earlier in experiments, and recently explained by classical and quantum models [Phys. Plasmas 21, 13302 (2014); Phys. Rev. E 91, 043102 (2015)]. Here, for the first time, we report this non-conventional collisional laser absorption by PIC simulation, thus bridging the gap between models, simulations, and experimental findings. Moreover, electron energy distributions naturally emanating during the laser interaction (in PIC simulations) are found to be anisotropic and non-Maxwellian in nature, leading to some deviations from the earlier analytical predictions.

http://bit.ly/2SEcJfO

Comparative study of discharge characteristics and associated film growth for post-cathode and inverted cylindrical magnetron sputtering

Abstract

In this study, an experimental investigation of a DC cylindrical magnetron discharge for argon gas in post-cathode (i.e. direct) and hollow-cathode (i.e. inverted) configurations was carried out. The discharge properties at different externally applied magnetic fields and operating pressures were measured and compared for both the configurations. The discharge current (I)–voltage (V) characteristics obey \({I\propto V^n}\) , where the value of n is in the range of 3–8. The discharge current increases linearly with the magnetic field in the post-cathode configuration, whereas it saturates at higher magnetic fields in the case of inverted configuration. Measurement of plasma potential indicated a considerable anode fall in the inverted magnetron configuration, whereas a negligible anode fall and strong cathode fall were observed in the case of post-cathode configuration. The plasma density and electron temperature, measured using a double Langmuir probe, were observed to be higher in the inverted magnetron configuration. The plasma density was found to be maximum at around 3–4 cm away from the respective inner electrode in both the configurations. A clear change in surface morphology of copper thin film was observed in the case of inverted magnetron configuration, which might be due to the extra ionisation near the anode owing to the anode fall.

http://bit.ly/2DMXRS8

Quantum quench dynamics of the one-dimensional Ising model in transverse field

Abstract

The quantum quench dynamics of the one-dimensional Ising model in transverse field is investigated using the quantum renormalisation group method. The analytic expression of concurrence C(t) is obtained, where the initial state is a superposition state which is constructed from the eigenstates of pure Ising system. The effect of parameter a in the period and range of concurrence are exhibited respectively in the vicinity of the critical point, which show scaling behaviour. When effective magnetic field g is big enough, the maximum limit value is 1.0. However, the minimum value is different, which is also dependent on the evolved time t.

http://bit.ly/2SFdvcu

A $$\mathcal{PT}$$ PT -symmetric simple harmonic oscillator

Abstract

We consider a simple harmonic oscillator with non-Hermitian term and study it classically and quantum mechanically. We conclude that this version of oscillator, which breaks parity and time reversal, displays all the features possessed by the usual harmonic oscillator. In particular, we calculate its spectrum, adiabatic invariance and Wigner functions, and show that there is a consistency between the classical and quantum descriptions.

http://bit.ly/2DLn4fH

A family of conservative chaotic systems with cyclic symmetry

Abstract

In this paper, we propose a family of circulant systems with conservative property. Various dynamical properties of the circulant systems are derived and investigated. Bifurcation plots are derived and presented for a system and the Lyapunov exponents are derived to show the existence of chaotic oscillations, and their sum being zero confirms the conservativeness for certain values of parameters. One of the proposed systems is then implemented in field programmable gate array (FPGA) to show the hardware reliability. We used the hardware–software co-simulation to see the phase portraits of the FPGA implemented system. The discrete integrators required for solving the initial value problem are implemented using the Euler's method. The register transfer level schematics of the FPGA implemented system and the resources used for the implementations are presented.

http://bit.ly/2SAIZAG

Determination of molybdenum target parameters for transmission X-ray tube: A Geant4 simulation study

Abstract

Carbon nanotube-based transmission X-ray tubes are widely used in different applications including mammography and X-ray fluorescence (XRF) experiment. Molybdenum (Mo) is one of the suitable target materials for this type of tube. In this paper, we used a well-known simulator, Geant4, to achieve some of the parameters of the Mo target. The optimum thickness for maximum production of usable X-ray from Mo target was obtained when it was exposed to the electron beam with an energy of 50 keV. In addition, according to the results, hemisphere geometry was recommended for the target at least for XRF application. By increasing target thickness, Mo acts as a filter resulting in limited X-ray energy. For estimating the target's temperature generation, the amount of deposited energy was also evaluated.

http://bit.ly/2DMXTcI

A statistical probe into the word frequency and length distributions prevalent in the translations of Bhagavad Gita

Abstract

A statistical study has been conducted on Bhagavad Gita. Four measures have been derived for the original text in Sanskrit and its translations in Hindi, English and French. First, word frequency distributions for the documents were modelled. Power law was observed with the longest tail in the case of Sanskrit. For other versions, the distributions well replicated the Zipf–Mandelbrot pattern. Second, the Kullback–Leibler (KL) divergence between the documents has been computed with the highest value recorded in all three translations from the Sanskrit text. Next, a Shannon entropy-based measure: vocabulary quotient has been calculated, which estimates the vocabulary richness the texts offer; the highest being in the case of Bhagavad Gita in Sanskrit. Finally, word-length distributions were obtained with the longest word length in Sanskrit. The results attribute to the inflectional nature of Sanskrit.

http://bit.ly/2SFdsxk

Minimal length Schrödinger equation via factorisation approach

Abstract

The fourth-order modified Schrödinger equation due to the generalised uncertainty principle is considered in one dimension with a box problem. The factorisation of fourth-order self-adjoint differential equations is then discussed and thereby the wave functions and energy spectra of the modified Schrödinger equation are derived.

http://bit.ly/2DTPvIL

Long-time dynamics of a vertical-cavity surface-emitting laser under optical feedback

Abstract

External optical feedback in vertical-cavity surface-emitting laser (VCSEL) is found to influence its output intensity. We studied the effect of the amount of total output polarisation feedback and polarisation-selective feedback on the output intensities of a VCSEL for a low-resolution sampling and for long temporal duration. A \(40~\mu \hbox {s}\) resolution time-series correlation analysis is performed for different feedback conditions and the characteristic dynamics is investigated. We found a correlated fluctuation in VCSEL output for a moderate amount of total feedback and polarised feedback. The period of such fluctuations is found to be reduced from total feedback to the polarised feedback of the system.

http://bit.ly/2SBUFDc

The impact of surface plasma on the total emission charge from PZST cathode induced by nanosecond electric pulse

Abstract

Electron emission from antiferroelectric ( \(\hbox {Pb}_{0.99}\hbox {Nb}_{0.02})\hbox {[(Zr}_{0.80}\hbox {Sn}_{0.20})_{0.952}\hbox {Ti}_{0.048}\hbox {]}_{0.98}\hbox {O}_{3}\) cathode has been investigated. The PZST cathode can maintain a metastable ferroelectric phase by the application of a high-enough field, thus implying three possibly pulse-loading configurations for electron emission measurements. The fact that emission charge is larger than the non-compensated charge indicates that the surface plasma contributes to the total emission charge. Furthermore, \(\chi _i \;(i=\text {A, B, C})\) , characterising the contribution of surface plasma to the total emission charge, was defined. It was found that the emission charge increases almost linearly with \(\chi _i \) . Our results are of great importance for a better understanding of electron emission in antiferroelectric / ferroelectric cathodes.

http://bit.ly/2DMXQxy

Electrical features in $$\hbox {AlGaN}/\hbox {GaN}$$ AlGaN / GaN high electron mobility transistors with recessed gate and undoped region in the barrier

Abstract

This study considers electrical parameters of \(\hbox {AlGaN}/\hbox {GaN}\) high electron mobility transistor (HEMT) with the recessed gate and un-doped region (URG-HEMT) in the barrier layer. We have investigated the main electrical factors such as the lateral electric field, breakdown voltage ( \(V_{\mathrm{B}})\) , drain current ( \(I_{\mathrm{D}})\) , threshold voltage ( \(V_{\mathrm{T}})\) , output conductance ( \(g_{\mathrm{o}})\) and gate capacitance ( \(C_{\mathrm{g}})\) . Simulation findings compare these parameters in the single heterostructure (SH-HEMT), recessed gate (RG-HEMT) and the proposed (URG-HEMT) structures. Regarding the simulation outcomes, the maximum lateral field in the URG is less than those in the SH and RG HEMTs. This improves the breakdown voltage of the suggested device up to 160 V, while the breakdown voltage in the SH and RG transistors is about 90 V. Therefore, breakdown voltage of the reported device is about 80% larger than that of the other transistors. Also, undoped region in the novel transistor reduces the output conductance and gate-to-drain capacitance. But, the recessed gate and undoped regions in the URG structure decrease in 2-DEG electron density and then reduce drain current.

http://bit.ly/2SAWRLp

Theoretical investigation of chemically reactive flow of water-based carbon nanotubes (single-walled and multiple walled) with melting heat transfer

Abstract

This study reports the chemically reacting flow of carbon nanotubes (CNTs) over a stretchable curved sheet. The flow is initialised due to a stretched surface. A heat source is present. Water is considered as the base liquid. The vital interest of this work is that heat phenomenon is studied via melting heat transfer. Xue relation of nanoliquid is implemented to explain the properties of both single- and multiwall CNTs. Mathematical systems (partial differential equations) for the flow field are obtained. Appropriate transformations are utilised in order to transform partial differential systems into nonlinear ordinary differential systems. Further, these systems are solved numerically. Variations in flow, temperature, concentration, skin friction coefficient and Nusselt number via the involved influential variables are illustrated graphically.

http://bit.ly/2DHj4wU

Comparison of substorm onsets during different levels of interplanetary magnetic field $$B_{z}$$ B z

Abstract

The magnetospheric response during the substorm events to solar wind driving, as determined by the level and sign of the interplanetary magnetic field (IMF) \(B_{z}\) , is analysed. Using the superposed epoch analysis, solar wind and geomagnetic conditions under three levels of \(B_{z}\) are characterised, i.e. northward or BZN ( \(B_{z} > 0~\hbox {nT}\) , 75 events), very weak or BZ0 ( \(B_{z } \sim 0~\hbox {nT}\) , 78 events) and southward or BZS ( \(B_{z} < 0~\hbox {nT}\) , 80 events). No northward turning is observed during BZS, while northward turning occurs 20 and 50 min prior to onset, during the BZN and BZ0 classes, respectively. IMF has a strong duskward component and the solar wind speed is also the fastest during BZN onsets. Auroral activity, as measured by the AL index, takes a longer time to decay to preonset values during BZ0 and BZS onsets compared to the BZN onsets. The level of IMF \(B_{z}\) does not seem to influence the oval thickness in the noon sector. The oval is the thinnest during BZ0 events in all the sectors. The rate of auroral widening in the dawn sector is found to be evidently slower than in the dusk sector during the BZS group.

http://bit.ly/2SDZ9sT

Synchronisation of integer-order and fractional-order discrete-time chaotic systems

Abstract

This paper studies the synchronisation of integer- and fractional-order discrete-time chaotic systems with different dimensions. Control laws are proposed for the full-state hybrid projective synchronisation (FSHPS) of a master–slave pair, where the difference equations of the master have an integer order while those of the slave have a fractional order. Moreover, inverse FSHPS laws are proposed for a fractional-order master and an integer-order slave. The Lyapunov stability theory of integer-order maps and the stability theory of linear fractional-order maps are utilised to establish the asymptotic stability of the zero equilibrium corresponding to the synchronisation error system. Numerical results are presented to verify the findings of the study.

http://bit.ly/2DHiXBu

Non-planar electron-acoustic waves with hybrid Cairns–Tsallis distribution

Abstract

Non-planar electron-acoustic waves having Cairns–Tsallis distributed hot electrons are investigated under multiple temperature electrons model in unmagnetised plasma. In this model, Korteweg–de Vries (KdV) equation is obtained in the cylindrical / spherical coordinates. On the basis of the solutions of KdV equation, variation of solitary wave features (amplitude, velocity and width) with different plasma parameters are analysed. Dispersion and nonlinear coefficients obtained depend on the particle density \(\alpha \) , non-extensive parameter q, electron temperature ratio \(\theta \) and non-thermal parameter \(\gamma \) . Combined effect of all these plasma parameters significantly changes the properties of the solitary waves in non-planar geometry. It is observed that increasing the number of non-thermal electrons in the medium increases the amplitude, velocity as well as width of the non-planar waves whereas with the increase in temperature, the velocity of waves decreases and this impact is dominant in spherical waves. This two-parameter \((\gamma , q)\) distribution model (C–T) is applicable to a wide range of observed plasmas, i.e. auroral region and magnetosphere of the Earth.

http://bit.ly/2SG7AE8

Histologic findings associated with laser interstitial thermotherapy for glioblastoma multiforme

Abstract

Background

Laser-interstitial thermal therapy (LITT) has been supported by some authors as an ablative treatment of glioblastoma multiforme (GBM). Although the effects of LITT have been modeled in vivo, the histologic effects in a clinical circumstance have not been described. We analyzed tissue from a patient who underwent LITT as primary treatment for GBM.

Case presentation

A 62-year-old male was diagnosed with a left temporal GBM and underwent LITT at an outside institution. Despite corticosteroid therapy, the patient was referred with increasing headache and acalculia associated with progressive peritumoral edema two weeks after LITT procedure. En bloc resection of the enhancing lesion and adjacent temporal lobe was performed with steroid-independent symptom resolution (follow-up, > 2 years). Histologic analysis revealed three distinct histologic zones concentrically radiating from the center of the treatment site. An acellular central region of necrosis (Zone 1) was surrounded by a rim of granulation tissue with macrophages (CD68) (Zone 2; mean thickness, 1.3 ± 0.3 mm [±S.D.]). Viable tumor cells (identified by Ki-67, p53 and Olig2 immunohistochemistry) were found (Zone 3) immediately adjacent to granulation tissue. The histologic volume of thermal tissue ablation/granulation was consistent with preoperative (pre-resection) magnetic resonance (MR)-imaging.

Conclusion

These findings are the first in vivo in humans to reveal that LITT causes a defined pattern of tissue necrosis, concentric destruction of tumor and tissue with viable tumor cells just beyond the zones of central necrosis and granulation. Furthermore, MR-imaging appears to be an accurate surrogate of tissue/tumor ablation in the early period (2 weeks) post-LITT treatment. Surgery is an effective strategy for patients with post-LITT swelling which does not respond to steroids.

http://bit.ly/2DHiM9i

A walk through tau therapeutic strategies

Abstract

Tau neuronal and glial pathologies drive the clinical presentation of Alzheimer's disease and related human tauopathies. There is a growing body of evidence indicating that pathological tau species can travel from cell to cell and spread the pathology through the brain. Throughout the last decade, physiological and pathological tau have become attractive targets for AD therapies. Several therapeutic approaches have been proposed, including the inhibition of protein kinases or protein-3-O-(N-acetyl-beta-D-glucosaminyl)-L-serine/threonine Nacetylglucosaminyl hydrolase, the inhibition of tau aggregation, active and passive immunotherapies, and tau silencing by antisense oligonucleotides. New tau therapeutics, across the board, have demonstrated the ability to prevent or reduce tau lesions and improve either cognitive or motor impairment in a variety of animal models developing neurofibrillary pathology. The most advanced strategy for the treatment of human tauopathies remains immunotherapy, which has already reached the clinical stage of drug development. Tau vaccines or humanised antibodies target a variety of tau species either in the intracellular or extracellular spaces. Some of them recognise the amino-terminus or carboxy-terminus, while others display binding abilities to the proline-rich area or microtubule binding domains. The main therapeutic foci in existing clinical trials are on Alzheimer's disease, progressive supranuclear palsy and non-fluent primary progressive aphasia. Tau therapy offers a new hope for the treatment of many fatal brain disorders. First efficacy data from clinical trials will be available by the end of this decade.

http://bit.ly/2S6qIG4

SET SUMOylation promotes its cytoplasmic retention and induces tau pathology and cognitive impairments

Abstract

PP2A is a major regulator of tau phosphorylation, which is principally regulated by an endogenous nuclear protein inhibitor 2 of PP2A (I₂^PP2A), also named SET. However, how SET is post-translationally regulated and translocates from the nucleus to the cytoplasm remain incompletely understood. Here we show SET is SUMOylated at K68 residue that induces its cytoplasmic retention, resulting in Alzheimer disease (AD) like tau pathology and cognitive defects. SET is predominantly SUMOylated at K68 that leads to its translocation from the nucleus to the cytoplasm and subsequently induces inhibition of PP2A and hyperphosphorylation of tau in HEK-293 cells. Moreover, overexpression of wild type SET significantly inhibits PP2A activity, leading to tau hyperphosphorylation, less synapse loss and cognitive deficits. Conversely, blocking SET SUMOylation via mutating Lys 68 to Arg rescues tau pathology and cognitive impairments in C57/BL6 mice infected with adeno-associated virus encoding SET. Further, β-amyloid exposure of rat primary hippocampal neurons induces a dose-dependent SUMOylation of SET. Our findings suggest that SET SUMOylation stimulates its cytoplasmic retention and inhibits PP2A activity, consequently leading to tau hyperphosphorylation and cognitive impairments, which provides a new insight into the AD-like tau pathology.

http://bit.ly/2X7ZVNI

Calcifying Epithelial Odontogenic (Pindborg) Tumor in a Child: A Case Report and Literature Review

Abstract

Calcifying epithelial odontogenic tumor (CEOT) is a rare neoplasm, which accounts for < 1% of all odontogenic tumors. CEOT occurs more frequently in adults with a peak incidence in the 5th decade of life and is extremely rare in the pediatric population. We present a case of a 13-year-old girl who was found to have a mandibular CEOT. We summarize the radiological features, pathological findings, clinical management and literature review focusing on this entity in children.

http://bit.ly/2SzYqJj

Efficacy of nintedanib and docetaxel in patients with advanced lung adenocarcinoma treated with first-line chemotherapy and second-line immunotherapy in the nintedanib NPU program

Abstract

Purpose

Both nintedanib/docetaxel and anti‐PD‐1/PD‐L1 immunotherapies have demonstrated efficacy as second‐line treatment of patients with advanced lung adenocarcinoma. This is the first report on the efficacy of the nintedanib/docetaxel combination following first‐line platinum‐based chemotherapy and subsequent immunotherapy in a real-world setting.

Methods/patients

From May 2014 to December 2015, 390 patients in 108 Spanish centres enrolled in the nintedanib named patient use program. Inclusion criteria were advanced lung adenocarcinoma with progressive disease following at least one line of platinum‐based doublet chemotherapy. The objective was to evaluate the efficacy of the nintedanib/docetaxel combination in patients who also received immunotherapy.

Results

Eleven patients met the inclusion criteria; with a median age of 67 years. PD‐L1 expression was positive in six patients. Median progression‐free survival (PFS) of first‐line platinum‐based chemotherapy was 3.3 months (95% CI 1.9–4.6). Second‐line immunotherapy was pembrolizumab (36.5%), atezolizumab (36.5%) or nivolumab (27%). Median PFS of second‐line immunotherapy was 2.3 months (95% CI 0–6.1). The overall response rate (ORR) to second‐line immunotherapy was 18% with a disease‐control rate (DCR) of 45%. Median PFS of nintedanib/docetaxel was 3.2 months (95% CI 1.9–4.5). Best response was partial response in four patients (36%), stable disease in five patients (46%), and progressive disease in two patients (18%), for an ORR of 36% and a DCR of 82%.

Conclusion

Our experience suggests an encouraging efficacy of nintedanib/docetaxel in patients with adenocarcinoma NSCLC pretreated with platinum‐based doublet chemotherapy and immunotherapy, reinforcing the importance of an optimal therapeutic sequence for managing advanced lung adenocarcinoma.

http://bit.ly/2IeLUdB

High-dose intravenous methylprednisolone therapy in patients with Graves’ orbitopathy is associated with the increased activity of factor VIII

Abstract

Purpose

Venous thromboembolic events (VTE), with their life-threatening manifestation as pulmonary embolism, are potential adverse effects of intravenous methylprednisolone (IVMP) pulse therapy, partially due to a hypercoagulable state. The aim of the study was to analyze the influence of IVMP on selected hemostatic parameters in patients with moderate-to-severe Graves' orbitopathy (GO).

Methods

26 euthyroid patients with GO were treated with 12 pulses of IVMP (6 × 0.5, 6 × 0.25 g every week). Hemostatic variables [factor (F) II, FV, FVII, FVIII, fibrinogen, antithrombin, activated partial thromboplastin time (aPTT), prothrombin time, international normalized ratio of prothrombin time, platelets and D-dimer] were analysed before, 24 and 48 h after 1st, 6th and 12th pulse.

Results

A constant, transient trend in changes of some hemostatic variables was observed after all assessed pulses. We discovered an increase in median activity of FVIII 24 and 48 h after pulses, with a shortening of aPTT 24 h after each IVMP pulse (p < 0.00005). FVII decreased 24 h after each pulse (p < 0.0005 after 1st and 12th, p < 0.00005 after 6th). Fibrinogen level decreased 48 h after each pulse (P < 0.00005). We did not observe any statistically significant changes in hemostatic parameters in the long-term evaluation. Therapy was concluded in one patient after the 9th pulse due to pulmonary embolism.

Conclusions

The increase of FVIII activity is a consequence of treatment with IVMP and occurs after each pulse. In patients with additional risk factors of VTE, anticoagulation prophylaxis should be considered.

http://bit.ly/2SSwzn7

Self-portrait with goiter: Antonio Ligabue

http://bit.ly/2NaFdIq

Guido Menzinger di Preussenthal (1934–2018)

http://bit.ly/2RwLvGP

Clinical analysis of cervical lymph node metastasis risk factors in patients with papillary thyroid microcarcinoma

Abstract

Purpose

Lymph node metastasis (LNM) is a vital prognosis factor in patients with papillary thyroid microcarcinoma (PTMC). The study tried to identify clinicopathological factors for LNM of PTMC.

Methods

The clinicopathological data of 1031 patients with PTMC were extracted and analyzed. Univariate and multivariate analyses were used to identify risk factors associated with cervical lymph node metastasis. ROC analysis was used to determine the ideal critical points of the sum of the maximum diameter of multifocal in a unilateral lobe.

Results

The probability of LNM, central lymph node metastasis (CLNM) and lateral lymph node metastasis(LLNM)of PTMC patients were 35.6, 33.7 and 5.6%, respectively. In addition, 1.9% PTMC had LLNM only. Male, age ≤ 40 years, tumor largest diameter ≥ 5 mm, multifocal, non-uniform echoic distribution, the sum of the maximum diameter of multifocal in a unilateral lobe ≥ 8.5 mm, tumors in the lower pole location were prone to CLNM. Ultrasound mix-echo, the sum of the maximum diameter of the multifocal ≥ 10.75 mm, tumors in the upper pole location were extremely prone to LLNM. T3 were prone to LLNM or skip LLNM.

Conclusions

According to the clinicopathological characteristics of PTMC, the cervical lymph nodes should be correctly evaluated to guide the surgical treatment.

http://bit.ly/2NaFbjM

In memory of Professor Domenico Andreani

http://bit.ly/2TiWRv6

Foetal radiation exposure caused by mechanical thrombectomy in large-vessel ischaemic stroke in pregnancy

Abstract

Purpose

There is overwhelming evidence for the clinical benefits that are derived following mechanical thrombectomy in large-vessel acute ischaemic stroke. The risk of stroke is elevated in pregnancy due to many factors. To date, there have been two reports, totalling five patients, who have undergone mechanical thrombectomy in pregnancy, thus demonstrating the feasibility of the procedure; however, there is no data on the radiation exposure to the mother or foetus related to this therapy.

Methods

We highlight the important technical considerations to minimise the risk of the procedure and report the estimated dose received by mother and foetus. We also compare these doses with those received during whole-body CT in trauma and CT pulmonary angiogram (CTPA) examinations.

Results

Three cases of mechanical thrombectomy were performed at separate tertiary referral neuroscience centres in the UK. Following diagnostic CT and mechanical thrombectomy, the total whole-body effective dose to the pregnant patient was significantly higher than in patients undergoing CTPA (p < 0.05), but not significant different compared to whole-body CT imaging in trauma patients. The estimated dose received by the foetus following diagnostic CT and mechanical thrombectomy was significantly lower than in whole-body imaging in trauma patients at p < 0.05, with no difference in estimated foetal dose compared to CTPA imaging.

Conclusion

The estimated doses received by the foetus during diagnostic stroke imaging and mechanical thrombectomy are equivalent to, or less than, purely diagnostic imaging in emergency situations.

http://bit.ly/2GLX2MC

Understanding Skin Screening Practices Among Children at Elevated Risk for Melanoma to Inform Interventions for Melanoma Prevention and Control

Abstract

Melanoma is the deadliest form of skin cancer. Screening can aid in early disease detection, when treatment is more effective. Although there are currently no consensus guidelines regarding skin screening for pediatric populations with elevated familial risk for melanoma, at-risk children with the help of their parents and healthcare providers may implement skin self-exams. Healthcare providers may also recommend screening practices for these children. The goal of the current study was to describe current screening behaviors and provider recommendation for screening among children of melanoma survivors. Parents of children with a family history of melanoma completed a questionnaire that included items on children's screening frequency, thoroughness, and who performed the screening. Seventy-four percent of parents reported that their children (mean age = 9.0 years, SD = 4.8) had engaged in parent-assisted skin self-exams (SSEs) in the past 6 months. Only 12% of parents reported that children received SSEs once per month (the recommended frequency for adult melanoma survivors). In open-ended responses, parents reported that healthcare providers had provided recommendations around how to conduct SSEs, but most parents did not report receiving information on recommended SSE frequency. Twenty-six percent of parents (n = 18) reported that children had received a skin exam by a healthcare provider in the past 6 months. The majority of children with a family history of melanoma are reportedly engaging in skin exams despite the lack of guidelines on screening in this population. Future melanoma preventive interventions should consider providing families guidance about implementing screening with their children.

http://bit.ly/2SzMOGl

Metachronous gastric cancer risk after endoscopic resection of early gastric cancer and H. pylori status

http://bit.ly/2S3diux

A Helicobacter pylor i screening and treatment program to eliminate gastric cancer among junior high school students in Saga Prefecture: a preliminary report

Abstract

Background

To present the strategies and preliminary findings of the first 3 years after implementing a Helicobacter pylori screening and eradication program to prevent gastric cancer in Saga Prefecture.

Methods

A screening and treatment program to eradicate H. pylori from third-grade junior high students was started in Saga Prefecture in 2016, using local governmental grants. Screening was with urinary anti-H. pylori antibody tests, followed by H. pylori stool antigen tests for students who were antibody positive. Those positive on both tests underwent H. pylori eradication by triple therapy based on a potassium-competitive acid blocker.

Results

From 2016 to 2018, the participation rate was 83.1% and the H. pylori infection rate was 3.1% (660/21,042). The participation rates were higher in 2017 (85.4%) and 2018 (85.9%) compared with 2016 (78.5%) (P < 0.0001), and the infection rate also decreased in a time-dependent manner (2016: 3.6%, 2017: 3.3%, 2018: 2.5%, P = 0.0001). In total, 501 students positive for H. pylori received eradication therapy (85.1% success) and adverse events occurred in 20 of these (4.0%). However, no serious complications occurred.

Conclusions

The H. pylori screening and eradication project for school students in Saga Prefecture has started successfully and we have seen both a steady increase in the participation rate and a steady decrease in the infection rate, without major safety concerns.

http://bit.ly/2X5NnX2

Artificial neural network-based prediction of effective thermal conductivity of a granular bed in a gaseous environment

Abstract

Artificial neural network (ANN), a machine learning technique, is employed to predict the effective thermal conductivity of granular assemblies in the presence of a stagnant gas. ANN is trained with the help of estimated thermal conductivities calculated through resistor network (RN) model. RN model considers the effect of the presence of stagnant gas and the gas pressure (Smoluchowski effect) for the calculation of effective thermal conductivity. Granular assemblies are generated and compacted through discrete element method (DEM). The ANN is trained to predict the effective thermal conductivity of a granular assembly for a set of measurable experimental parameters (stress and packing fraction) without requiring the knowledge of microstructural details (coordination numbers and overlaps) of the assembly. The predicted effective thermal conductivity values through ANN are in good agreement with the experimental results. Estimation of effective thermal conductivity through the trained ANN is much faster (few seconds compared to few hours required for DEM together with RN approach) with very good accuracy.

http://bit.ly/2SDSLlp

Dislocation of intra-abdominal drains after pancreatic surgery: results of a prospective observational study

Abstract

Purpose

The use of intra-abdominal drains after major surgical procedures represents a well-established but controversial practice. No data are available regarding both the occurrence and the potential impact of their postoperative accidental dislocation. The aim of this study is to assess the actual rate of dislocation of intra-abdominal drains postoperatively and to evaluate its clinical impact.

Methods

This is a prospective observational study using major pancreatic surgery as a model. Ninety-one consecutive patients undergoing pancreatoduodenectomy (PD) or distal pancreatectomy (DP) underwent low-dose, non-enhanced computed tomography (LDCT) on postoperative days (POD) 1 and 3 in a blinded fashion to assess the position of drains. We compared the outcomes of patients with dislocated and correctly placed drains.

Results

Overall, drains were dislocated in 30 patients (33%), without differences between PD and DP. Most of dislocations were already present on POD 1 (77%). Postoperative complications occurred in 57% of patients, and the rate of postoperative pancreatic fistula (POPF) was 27%. The dislocated cohort had lesser morbidity (40% vs. 66%; relative risk (RR), 0.35; 95% CI, 0.14–0.86; P = 0.020), and the rate of POPF (3% vs. 39%, respectively; RR, 0.05; 95% CI, 0.01–0.42; P < 0.001). After PD, patients with dislocated drains had a shorter hospital stay (12 vs. 20 days; P = 0.015). No significant differences in terms of need for percutaneous drainage procedures, abdominal collections, or grade C POPFs were found between the groups.

Conclusions

Dislocation of intra-abdominal drains is an early and frequent event after major pancreatic resection. Its occurrence might protect against the negative effects of maintaining drainage, eventually leading to better postoperative outcomes. This data reinforces the knowledge that surgical drains might be detrimental in selected cases.

http://bit.ly/2BDFUFs

Addition of Serine Enhances Protein Analysis by DESI-MS

Abstract

Previous studies have suggested that the loss in sensitivity of DESI-MS for large molecules such as proteins is due to the poor dissolution during the short time scale of desorption and ionization. An investigation into the effect of serine as a solvent additive leads to the interesting observation that there is a concentration-dependent improvement in protein signal intensity when micromolar to low millimolar concentrations of serine is combined with a suitable co-additive in DESI spray. This effect, however, was not observed during similar ESI-MS experiments, where the same solvents and proteins were sprayed directly into the MS inlet. This suggests that the mechanism of signal improvement in DESI is associated with the desorption step of proteins, possibly by facilitating dissolution or improving solubility of proteins on the surface in the solvent micro-layer formed during DESI. Other than poor dissolution, cation adduction such as by sodium ions is also a major contributing factor to the mass-dependent loss in sensitivity in both ESI and DESI, leading to an increase in limits of detection for larger proteins. The adduction becomes a more pressing issue in native-state studies of proteins, as lower charge states are more susceptible to adduction. Previous studies have shown that addition of amino acids to the working spray solution during ESI-MS reduces sodium adduction and can help in stabilization of native-state proteins. Similar to the observed reduction in sodium adducts during native-state ESI-MS, when serine is added to the desorbing spray in DESI-MS, the removal of up to 10 mM NaCl is shown. A selection of proteins with high and low pI and molecular weights was analyzed to investigate the effects of serine on signal intensity by improvements in protein solubility and adduct removal.

Graphical Abstract

http://bit.ly/2SGDbG1

Evidence for personalised medicine: mechanisms, correlation, and new kinds of black box

Abstract

Personalised medicine (PM) has been discussed as a medical paradigm shift that will improve health while reducing inefficiency and waste. At the same time, it raises new practical, regulatory, and ethical challenges. In this paper, we examine PM strategies epistemologically in order to develop capacities to address these challenges, focusing on a recently proposed strategy for developing patient-specific models from induced pluripotent stem cells (iPSCs) so as to make individualised treatment predictions. We compare this strategy to two main PM strategies—stratified medicine and computational models. Drawing on epistemological work in the philosophy of medicine, we explain why these two methods, while powerful, are neither truly personalised nor, epistemologically speaking, novel strategies. Both are forms of correlational black box. We then argue that the iPSC models would count as a new kind of black box. They would not rely entirely on mechanistic knowledge, and they would utilise correlational evidence in a different way from other strategies—a way that would enable personalised predictions. In arguing that the iPSC models would present a novel method of gaining evidence for clinical practice, we provide an epistemic analysis that can help to inform the practical, regulatory, and ethical challenges of developing an iPSC system.

http://bit.ly/2toW6WL

Comparison of the Extent Classification and the New Complexity Classification of Hepatectomy for Prediction of Surgical Outcomes: a Retrospective Cohort Study

Abstract

Background

In predicting the risk for posthepatectomy complications, hepatectomy is traditionally classified into minor or major resection based on the number of resected segments. Recently, a new hepatectomy complexity classification was proposed. This study aimed to compare the value of the traditional and that of the new classification in perioperative outcomes prediction.

Methods

Demographics, perioperative laboratory tests, intraoperative and postoperative outcomes, and follow-up data of patients with hepatocellular carcinoma who underwent liver resection were retrospectively analyzed.

Results

A total of 302 patients were included in our study. Multivariable analysis of intraoperative variables showed that the complexity classification could independently predict the occurrence of blood loss > 800 mL, operation time > 4 h, intraoperative transfusion, and the use of Pringle's maneuver (all p < 0.05). For postoperative outcomes, the high-complexity group was independently associated with severe complications, and hepatic-related complications (all p < 0.05); the traditional classification was independently associated only with posthepatectomy liver failure (PHLF) (p = 0.004).

Conclusions

Complexity classification could be used to assess the difficulty of surgery and was independently associated with postoperative complications. The traditional classification did not reflect operation complexity and was associated only with PHLF.

http://bit.ly/2N8MPeq

Visual inspection of transvaginal ultrasound videos to characterize uterine peristalsis: an inter-observer agreement study

Abstract

Purpose

Contractions in non-pregnant uterine can be assessed by visual inspection of transvaginal ultrasound (TVUS). Many authors have used this method to extract features like contraction frequency and direction. However, visual inspection is a subjective method and the outcome is dependent on the sonographers and video analysts. In this study, we wanted to see which uterine feature is reproducible enough, in terms of inter-observer agreement, to serve as a reliable control for future research.

Methods

Six observers assessed 80 TVUS videos, and rated video quality, contraction frequency, direction and timing. One observer assessed operating time. A Fleiss' kappa (κ) or an intra-class correlation (ICC) was calculated to determine the inter-observer agreement of all features.

Results

The inter-observer agreement in frequency was substantial (ICC = 0.68). Conversely, there was just slight to fair agreement in contraction timing and direction and in video quality: ICC = 0.26, κ = 0.17 and κ = 0.16, respectively. Overall, agreement among technical engineers was better than between medical professionals. The level of agreement was correlated with video quality, phase of the menstrual cycle and individual patient (all χ² with p < 0.00). The time to analyze one video ranged between 6 and 20 min.

Conclusions

This study shows that visual inspection of TVUS videos is a fairly reproducible method to assess contraction frequency. However, the operating time is too extensive to implement this method in daily practice. Automated methods could offer a solution for this problem in the future.

http://bit.ly/2SWbwQC

Is contrast-enhanced ultrasound (CEUS) superior to computed tomography angiography (CTA) in detection of endoleaks in post-EVAR patients? A systematic review and meta-analysis

Abstract

Objective

The purpose of this systematic review and meta-analysis was to assess the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) compared to computed tomography angiography (CTA) for the detection of endoleaks within endovascular aortic aneurysm repair (EVAR) surveillance at time of follow up.

Methods

A comprehensive literature search was undertaken among the four major databases (PubMed, Embase, Scopus and Ovid) to identify all articles assessing diagnostic specificity and accuracy with comparative modality (CEUS vs CTA) for endoleaks in adult patients at time of follow-up following EVAR. Databases where evaluated and assessed to October 2018.

Results

A total of 1773 patients were analysed from across 18 included studies in the quantitative analysis of the parameters of interest. There was no significant difference in detection rate of endoleak type I with detection rate 4.3% for both groups OR 1.09, 95% CI [0.78, 1.53], p = 0.62; type II endoleak detection rate was 22% in the CEUS group vs 23% in the CTA group OR 1.16, 95% CI [0.75–1.79], p = 0.50; while type III detection rate was 1.8% in CEUS group vs 2% in CTA group OR 0.85, 95% CI [0.43, 1.68], p = 0.64. However, the sensitivity rate for endoleak detection was higher in CEUS (p = 0.001) while no difference in specificity rate was noted (p = 0.28). There was higher rate of missed endoleaks in CTA groups (n = 12 vs n = 20).

Conclusion

Evidences from this study suggest that contrast-enhanced ultrasound scan post-EVAR can be utilised as safe and effective method in screening for endoleaks during post-EVAR surveillance without exposing the patient for additional risk of radiation and contrast. CEUS conveys no inferiority to CTA in detecting endoleaks.

http://bit.ly/2N8MFUm

Use of the Xi robotic platform for total abdominal colectomy: a step forward in minimally invasive colorectal surgery

Abstract

Background

The use of the da Vinci robotic platform for total colectomy has been limited by the need to reposition the patient-side surgical cart from one side of the patient to the other, which increases operative time. In this study, we examined the feasibility of robotic total colectomy using the da Vinci Xi model, which offers a rotating boom-mounted system and laser-targeted trocar positioning.

Methods

The study cohort consisted of 23 patients who underwent minimally invasive total colectomy for cancer or polyposis syndromes at a comprehensive cancer center between 2015 and 2017. Of the 23 colectomies, 15 were robotic and eight were laparoscopic. For the robotic colectomies, trocars were placed in the supraumbilical region and all four quadrants. The da Vinci Xi robot was placed between the patient's legs, and the boom was rotated from left to right and then to the middle in order to work sequentially on the right colon, the left colon, and the pelvis. Operating time and short-term outcomes were compared between the patients who underwent robotic surgery and the patients who underwent laparoscopic surgery.

Results

The two groups of patients were comparable in age, gender, BMI, physical status, and disease types. In the robotic group, median length of stay (4 vs. 6 days, p = 0.047) was significantly shorter and median operative time (243 vs. 263 min, p = 0.97) and median estimated blood loss (50 vs. 100 ml; p = 0.08) were similar between the groups.

Conclusions

With the da Vinci Xi boom-mounted system, total abdominal colectomy can be performed without the need to move the patient-side surgical cart and is associated with shorter length of stay and similar operative time compared to the laparoscopic approach.

http://bit.ly/2TR9y17

Concomitant ventral hernia repair and bariatric surgery: a retrospective analysis from a UK-based bariatric center

Abstract

Background

Ventral hernias (VH) are frequently encountered in patients with morbid obesity. Concomitant ventral hernia repair (VHR) and bariatric surgery (BS) is practiced but still controversial. Wound-related complications (seroma, hematoma, wound infection) and hernia recurrence rates are possible inhibitor factors. We aimed to estimate the rate of complications from concomitant BS (laparoscopic Roux-en-Y gastric bypass and sleeve gastrectomy) and VHR and identify patient subgroups at higher risk of complications from synchronous repair.

Methods

A retrospective analysis of successive 106 patients who underwent concomitant BS + VHR at our institute (09/2007 to 09/2015) was performed using data from patients' record. Parameters considered were: type of repair (open/laparoscopic and primary closure/mesh), size and type of hernia (< 5 cm, 5–10 cm, > 10 cm and primary/incisional), patient gender and comorbidities.

Results

One hundred and six patients underwent concomitant BS and VHR. Fifty-nine had laparoscopic VHR and 47 open. Hernias recurred in 5 (8.47%) laparoscopic and 7 (14.89%) open VHR. Wound-related complications were common in open (15%) vs. laparoscopic (11.7%) VHR. Patients with VH recurrence included 8 (75%) with defects > 5 cm, 10 (83%) female, and all had BMI > 45. Six patients had wound infection, 5 of which had type 2 diabetes mellitus. Six patients had hematoma, 5 of which underwent mesh repairs. Finally, four patients developed seroma (BMI > 48, defects > 5 cm, laparoscopic mesh repair).

Conclusion

Synchronous VHR and BS in a bariatric unit is feasible with low recurrence rate. Laparoscopic VHR has lower complication rates than open, apart from seroma formation. Patients with diabetes have higher risk of infection.

http://bit.ly/2BBUoFW

Diagnosis and treatment of gastric antral webs in pediatric patients

Abstract

Background

Gastric antral webs are mucosal structures, varying from fenestrated diaphragms to mucosal crescents, resulting in varying degrees of foregut obstruction. Patients commonly present with vomiting, failure to thrive, and abdominal pain. Prevalence is unknown, and diagnosis can be difficult.

Methods

We performed an IRB-approved retrospective review of patients from 4/1/2015–4/1/2018 at a Level I Children's Surgery Center undergoing gastric antral web resection. Data obtained included demographics, preoperative workup, surgical repair, and outcomes.

Results

Twenty-one patients were identified; 67% were male with an average age of 30 months at diagnosis. Initial diagnosis was established by a combination of fluoroscopy and esophagogastroduodenoscopy (EGD) in all patients. Patients presented with emesis (76%), failure to thrive (57%), need for post-pyloric tube feeds (33%), and abdominal pain (14%). Web localization without intraoperative EGD (n = 3) was initially challenging. As a result, intraoperative EGD was combined with operative antral web resection to facilitate web localization (n = 18). Web marking techniques have evolved from marking with suture (n = 1) and tattoo (n = 2), to endoscopic clip application (n = 12). All 21 patients underwent web resection, 2 were performed laparoscopically. Twenty underwent Heineke-Mikulicz pyloroplasty during the initial surgery. Average length of stay was 5.5 days. There were no intraoperative complications or deaths. Permanent symptom resolution occurred in 90% of patients immediately, with a statistically significant decrease in emesis (p < 0.001), failure to thrive (p < 0.001), and need for post-pyloric tube feeding (p = 0.009) within 6 months of surgery.

Conclusion

Gastric antral webs should be considered in the differential diagnosis for a child with persistent vomiting. Web resection with the use of intraoperative endoscopic localization can result in permanent symptom resolution in the majority of these patients.

http://bit.ly/2BDl1u9

Retroperitoneoscopic partial nephrectomy in children: a multicentric international comparative study between lateral versus prone approach

Abstract

Background

Very limited informations are currently available about the best approach to perform retroperitoneoscopic surgery. This multicentric international study aimed to compare the outcome of lateral versus prone approach for retroperitoneoscopic partial nephrectomy (RPN) in children.

Methods

The records of 164 patients underwent RPN in 7 international centers of pediatric surgery over the last 5 years were retrospectively reviewed. Sixty-one patients (42 girls and 19 boys, average age 3.8 years) were operated using lateral approach (G1), whereas 103 patients (66 girls and 37 boys, average age 3.0 years) underwent prone RPN (G2). The two groups were compared in regard to operative time, postoperative outcome, postoperative complications, and re-operations.

Results

The average operative time was significantly shorter in G2 (99 min) compared to G1 (160 min) (p = 0.001). Only 2 lateral RPN required conversion to open surgery. There was no significant difference between the two groups as for intraoperative complications (G1:2/61, 3.3%; G2:6/103, 5.8%; p = 0.48), postoperative complications (G1:9/61, 14.7%; G2:17/103, 16.5%; p = 0.80), and re-operations (G1:2/61, 3.3%; G2:4/103, 3.8%; p = 0.85). Regarding postoperative complications, the incidence of symptomatic residual distal ureteric stumps (RDUS) was significantly higher in G2 (7/103, 6.8%) compared to G1 (1/61, 1.6%) (p = 0.001). Most re-operations (4/6, 66.6%) were performed to remove a RDUS .

Conclusions

Both lateral and prone approach are feasible and reasonably safe to perform RPN in children but the superiority of one approach over another is not still confirmed. Although prone technique resulted faster compared to lateral approach, the choice of the technique remains dependent on the surgeon's personal preference and experience. Our results would suggest that the lateral approach should be preferred to the prone technique when a longer ureterectomy is required, for example in cases of vesico-ureteral reflux into the affected kidney moiety, in order to avoid to leave a long ureteric stump that could become symptomatic and require a re-intervention.

http://bit.ly/2TORhBq

Comparison of early experience of robotic and transanal total mesorectal excision using propensity score matching

Abstract

Background

Robotic surgery and transanal minimally invasive surgery are the two recently developed techniques, which can overcome the difficult pelvic dissection in conventional laparoscopy. This study aimed to compare the early cases of robotic and transanal total mesorectal excision (taTME) using propensity score matching.

Methods

The first 40 cases of taTME and the first 80 sphincter-saving robotic total mesorectal resection for rectal cancer were selected from the prospectively collected database. Using propensity score matching, the outcomes of 40 matched cases of robotic TME were compared with the 40 cases of taTME.

Results

Before matching, patients in the taTME group were significantly younger. The tumors were smaller but more distally located. Significantly more patients in the taTME group received preoperative chemoradiation. After matching, the two groups did not show any differences in gender, age, comorbidity, the level of tumors, and incidences of preoperative chemoradiation. The operating time was significantly shorter (254 vs. 170 min, p < 0.05) and the blood loss was less (50 vs. 150 ml, p = 0.002) in the taTME group. Conversion rate was 5% in both groups. There was no difference in the hospital stay, overall morbidity, the anastomotic leakage rate, and the urinary complication rate between the two groups. More patients in the taTME group did not require a separate abdominal incision. The distal margin, the number of lymph nodes examined, and the rate positive circumferential margin (0 vs. 5%, p = 0.494) were also similar between the two groups.

Conclusions

Both taTME and robotic surgery can achieve favorable outcomes in the rectal cancer resection. Comparison of the early experience of the two procedures with propensity score matching showed the taTME was associated with a shorter operating time, less blood loss, and a higher rate of transanal extraction of the specimen. Further evaluation by randomized trials is warranted.

http://bit.ly/2BF5PfZ

Peritoneal perforation during transanal endoscopic microsurgery is not associated with significant short-term complications

Abstract

Background

In patients treated by transanal endoscopic microsurgery (TEM), breach of the peritoneal cavity is a feared intraoperative challenge. Our aim is to analyze predictors and short-term outcomes of patients with peritoneal perforation (TEM-P) when compared to similar patients with no peritoneal compromise (TEM-N).

Methods

At St. Paul's Hospital, demographic, surgical, pathologic, and follow-up data for all patients treated by TEM is maintained in a prospectively populated database. A retrospective review was performed and two groups were established for comparison: TEM-P and TEM-N. Statistical analysis was performed using student's t or chi-squared test, where appropriate.

Results

Of 619 patients treated by TEM between 2007 and 2016, 39 (6%) patients were in the TEM-P group and 580 (94%) in the TEM-N group. There were no differences between the groups in patient age, gender, histology, or tumor size. Patients who had peritoneal perforations had more proximal lesions (11 vs. 7 cm, p < 0.0001), anterior lesions (56 vs. 43%, p < 0.05), and longer operations (80 vs. 51 min, p < 0.005). While most defects were closed endoluminally, 2 patients with perforation were converted to transabdominal surgery. There was a difference in overall hospital stay with TEM-P patients staying on average 2 days in hospital with fewer patients managed as day surgery (31 vs. 73%, p < 0.0001). There were no mortalities or significant 30-day complications in the TEM-P group and only one patient required readmission.

Conclusions

The St. Paul's Hospital TEM experience suggests patients with peritoneal breach during TEM can be safely managed with outcomes similar to patients without peritoneal entry. Proximal, anterior lesions are at highest risk of peritoneal perforation.

http://bit.ly/2TQZvZZ

Operating hurts: a study of EAES surgeons

Abstract

Background

Work-related pain and discomfort experienced by surgeons is widely reported in the literature. A survey was, therefore, conducted to explore this issue among members of the European Association for Endoscopic Surgery (EAES).

Methods

The survey was emailed to 2980 EAES members in 2017 enquiring about their working practice, musculoskeletal (MSK) pain and burnout.

Results

A total of 569 (19%) surgeons responded, of whom 556 were practicing surgeons; 86% were consultants, 84% were male, and 94% were right-handed. Respondents operated on average 3.3 days/week with 27% of their procedures lasting longer than 3 h. The 386 endoscopists surveyed reported performing an average of 5.3 procedures/day with 83% performing endoscopy at least once per week. Over half of practicing surgeons (62%) reported their worst pain score was 3 or higher (10-point scale) in the past 7 working days, encompassing 71% of their open, 72% laparoscopic, 48% robot-assisted cases and 52% of their endoscopies. Of the 120 surgeons who had ever sought medical help for aches, pain or discomfort, 38% were currently in pain and 16% had considered leaving surgery due to their MSK pain, 26% had reported work-related pain to their employer, 26% had been on short-term disability during their career and 4% long-term disability due to MSK disorders. A significant proportion of the respondents (49%) felt their physical discomfort would influence the ability to perform or assist with surgical procedures in the future. These surgeons reported significantly lower satisfaction from their work (p = 0.024), higher burnout (p = 0.005) and significantly higher callousness toward people (p < 0.001) than those not fearing loss of career longevity.

Conclusion

The results show that MSK pain is prevalent amongst EAES members. Nearly half the respondents had career longevity fears from pain/discomfort which, in turn, correlated with more prevalent feelings of burnout. More emphasis should be placed on the aetiology, prevention and management of musculoskeletal pain in the surgical workforce.

http://bit.ly/2TTSwPS

Bile duct injuries (BDI) in the advanced laparoscopic cholecystectomy era

Abstract

Background

Laparoscopic cholecystectomy is the most commonly performed laparoscopic procedure. It is superior in nearly every regard compared to open cholecystectomies. The one significant aspect where the laparoscopic approach is inferior regards the association with bile duct injuries (BDI). The BDI rate with laparoscopic cholecystectomy is approximately 0.5%; nearly triple the rate compared to the open approach. We propose that 0.5% BDI rate with the laparoscopic approach is no longer accurate.

Methods

The National Surgical Quality Improvement Program (NSQIP) registry was retrospectively reviewed. All laparoscopic cholecystectomies performed between 2012 and 2016 were extracted. A total of 217,774 cases meeting inclusion criteria were analyzed. The primary data points were the overall BDI incidence rate and time of diagnosis. BDI were identified by ICD-9 and ICD-10 codes. Secondary data points were variables associated with BDI.

Results

The BDI rate was 0.19%. 77% of cases were diagnosed after the index surgical admission. Intra-operative cholangiography (IOC) use was associated with a higher BDI rate and higher identification rate of a BDI intraoperatively (P value < 0.0001). Resident teaching cases were protective with a RR score of 0.56 (P value < 0.0001). The presence of cholecystitis increased the risk of a BDI with a RR score of 1.20 (P value < 0.0001). There was a low conversion rate of 0.04% however converted cases had a nearly hundredfold increase in BDI at 15% (P value < 0.0001).

Conclusions

The performance of laparoscopic cholecystectomies in North America is no longer associated with higher BDI rates compared to open. IOC use still is not protective against BDI, and cholecystitis continues to be a risk factor for BDI. When a cholecystectomy requires conversion from a laparoscopic to an open approach the BDI increases a hundredfold; which may raise the concern if this approach is still a safe bailout method for a difficult laparoscopic dissection.

http://bit.ly/2BDiWhz

Safety of laparoscopic hepatectomy in patients with hepatocellular carcinoma and portal hypertension: interim analysis of an open prospective study

Abstract

Background

The laparoscopic approach might increase the number of cirrhotic patients with hepatocellular carcinoma (HCC) indicated for liver resection, otherwise contraindicated due to portal hypertension. The goal of this study was to confirm the safety of laparoscopic liver resection (LLR) in patients with portal hypertension.

Methods

This prospective, single-center, open study (ClinicalTrials.gov ID: NCT02145013) included all consecutive cirrhotic patients who underwent LLR for HCC from 2014 to 2017. Short-term outcomes were compared between patients with and without clinically significant portal hypertension (CSPH, defined by hepatic venous pressure gradient ≥ 10 mmHg).

Results

The study population included 45 patients, comprising 27 patients (60%) in the no CSPH group and 18 patients (40%) in the CSPH group. All planned procedures could be performed. The two groups did not differ in the extent of resection, transfusion, duration of clamping, and need for conversion. Overall, the 90-day mortality and severe morbidity rates were nil. Moderate morbidity was significantly higher in the CSPH group (39 vs. 4%, p = 0.01); however, the two groups did not differ in the rate of unresolved liver decompensation. Intensive care unit and hospital stays were significantly longer in the CSPH group. At 2 years, overall survival was 77% in the no CSPH group and 100% in the CSPH group (p = 0.17), and recurrence-free survival was 55% in the no CSPH group and 79% in the CSPH group (p = 0.10).

Conclusion

LLR is safe in BCLC 0-A patients with CSPH, with no mortality and good short-term outcomes. Re-evaluation of the BCLC guidelines is needed.

http://bit.ly/2TQZvJt

Correction to: Facilitating endoscopic submucosal dissection: double balloon endolumenal platform significantly improves dissection time compared with conventional technique (with video)

Gerd Silberhumer's name was misspelled in the original publication; it is correct as displayed here.

http://bit.ly/2BH5Pfr

Comparison of impacts of intraperitoneal saline instillation with and without pulmonary recruitment maneuver on post-laparoscopic shoulder pain prevention: a randomized controlled trial

Abstract

Background

Intraperitoneal isotonic saline instillation (SI) and pulmonary recruitment maneuver (RM) were indicated to alleviate post-laparoscopic shoulder pain (PLSP) effectively. The aim of this study was to compare the effects of the single strategy using SI alone and the combined strategy using SI and RM on PLSP reduction.

Methods

Subjects undergoing elective gynecologic laparoscopy were randomly allocated to a control group (no intervention, n = 48) and two intervention groups (single strategy of SI alone, n = 48; combined strategy of SI and RM, n = 48). In the control group, carbon dioxide was removed only via passive evacuation through the port sites at the completion of the laparoscopic procedure. In the saline instillation group, 20-mL/kg of body weight SI was performed. In the combined strategy group, RM using five pulmonary inflations was performed, in addition to SI. The PLSP scores, which were the primary outcome, were recorded using a visual analog scale postoperatively.

Results

The PLSP scores 24 and 48 h after surgery were significantly lower in the two intervention groups than in the control group (P = 0.014 and P = 0.001, respectively), while no significant differences were observed between the two intervention groups.

Conclusions

The single strategy using SI alone is as effective as the combined strategy of SI and RM for removing residual carbon dioxide and consequently preventing PLSP. Therefore, considering the potential risks of pulmonary or hemodynamic complications associated with RM, the single strategy using SI alone might be a better choice than the combined strategy.

http://bit.ly/2TR9zCd

Clinicopathological characteristics of patients with pain after endoscopic submucosal dissection for gastric epithelial neoplasm

Abstract

Background

Endoscopic submucosal dissection (ESD) is widely used for large superficial gastrointestinal tumors. Epigastric pain is a frequent complication of ESD. However, little is known about its incidence and associated factors. This study evaluated pain incidence and characteristics of patients with pain after gastric ESD.

Methods

We retrospectively analyzed a prospectively collected registry of clinical, endoscopic, and pathologic results of patients who underwent ESD for gastric adenoma or cancer from January 2010 to December 2015. A Visual Analogue Scale (VAS) was used to assess pain immediately after, and 2, 12, and 24 h after ESD. The primary outcome was the use of painkillers (VAS score > 4). Analyzed data included age, sex, pathology, specimen and tumor size, procedure time, and tumor location.

Results

Of 1226 patients, 461 (36.4%) needed a painkiller at least once after ESD (pain group). Compared with the no pain group, the pain group had more females, less alcohol consumption, larger tumor and specimen size, and more antral lesions. In multivariate analysis, female sex (OR 1.559, 95% CI 1.217–1.996, p < 0.001), antral tumor location (OR 1.780, 95% CI 1.398–2.265, p < 0.001), and procedure time over 30 min (OR 1.443, 95% CI 1.130–1.842, p = 0.003) were predictive factors for pain.

Conclusion

This study showed that a considerable number of patients needed one or more painkiller doses after gastric ESD. The factors affecting pain included sex, procedure time, and lesion location. Endoscopists should use preemptive or aggressive pain management in high-risk patients after ESD.

http://bit.ly/2BBOLr2

Assessing variation in technique for sleeve gastrectomy based on outcomes of surgeons ranked by safety and efficacy: a video-based study

Abstract

Background

Considerable technical variation exists when performing laparoscopic sleeve gastrectomy (LSG). However, little is known about which techniques are associated with optimal outcomes.

Objective

To compare technical variation among surgeons with the lowest complication rates and whose patients achieved the most weight loss.

Methods

Practicing bariatric surgeons (n = 30) voluntarily submitted a video of a typical LSG performed between 2015 and 2016. Technique-specific data captured from videos and a questionnaire included bougie size, stapler vendor, number of staple loads, use of staple line reinforcement, fibrin sealant, intraoperative leak test, endoscopy, and drain placement. Surgeon-specific outcomes were obtained from cases performed by surgeons during the study period (n = 7023) using a state-wide bariatric-specific data registry. Surgeons were ranked based on 30-day risk-adjusted surgical complication rates ("safety") and excess body weight loss (EBWL) % ("efficacy") at 1 year after surgery. Technique-specific variables were compared between surgeons ranked in the top and bottom quartile for both safety and efficacy.

Results

Surgical complication rates ranged from 0 to 4.32% while EBWL varied from 45.3 to 65.3%. There was no correlation between surgeon rankings for safety and efficacy (Pearson's r = 0.063, p = 0.741). Surgeons ranked in the top quartile for safety and efficacy had significantly shorter mean operative times than surgeons ranked in the bottom quartile (65 min vs. 69 min, p < 0.0001). Surgeons with the highest leak rates were more likely to use buttressing (85.7% vs 40.0%, p = 0.032), otherwise operative techniques varied considerably.

Conclusions

Technical variation appears to have minimal effect on the safety or efficacy of sleeve gastrectomy among surgeons participating in a state-wide quality improvement collaborative. Top ranked surgeons did have faster mean operative times indicating that there may be other metrics of technical quality that correlate to optimal outcomes.

http://bit.ly/2TRVHHQ

Laparoscopic versus open resection of gastrointestinal stromal tumors: survival outcomes from the NCDB

Abstract

Background

Studies comparing laparoscopic versus open resection of gastrointestinal stromal tumors (GIST) typically involve small comparative groups and often do not control for tumor size or stage of disease. The objective of this study was to compare adjusted survival outcomes for laparoscopic versus open GIST.

Method

The National Cancer Database (NCDB) from 2010 to 2014 was evaluated for gastric and small intestinal GIST resections. After stratification by disease stage and adjustment for patient demographics, comorbidity score, tumor size, and tumor location, 90-day mortality rates were compared based on laparoscopic versus open resection. Kaplan–Meier estimates of long-term survival were also compared. A Cox proportional hazards model was used to determine hazard ratios (HR) for survival.

Results

There were 5096 cases analyzed, including 2910 (57%) stage I, 954 (19%) stage II, and 1232 (24%) stage III cases. The distribution of laparoscopic versus open cases was 1291 (44%) versus 1619 (56%) for stage I, 318 (33%) versus 636 (67%) for stage II, and 286 (23%) versus 946 (77%) for stage III. There was no significant difference in adjusted 90-day mortality between laparoscopic and open resection. Kaplan–Meier estimates of long-term survival demonstrated improved overall survival curves for laparoscopic resection for stage I and stage II disease, but no significant difference for stage III disease. Factors associated with statistically significant higher adjusted overall mortality included older age (HR 1.06; p < 0.001), black race (HR 1.33; p = 0.04), higher comorbidity score (HR 1.47; p < 0.001), and small intestinal versus gastric tumor location (HR 1.28; p = 0.03). The hazards model suggested improved overall survival for females (HR 0.59; p < 0.001) and laparoscopic approach (HR 0.80; p = 0.06).

Conclusion

Laparoscopic and open GIST resection have comparable 90-day mortality with possible improved long-term survival with laparoscopy for early-stage disease. These findings support the use of laparoscopy as a viable and potentially more effective approach to GIST resection.

http://bit.ly/2BCRrEV

Sclerotherapy needle injections can expand the subserosal and muscularis propria layers and cause a stable mucosal lift in ESD/EMR patients

Abstract

Background

A mucosal lift is needed for ESD and EMR. Most lifts are made via sclerotherapy needle injection. The firm push needed to penetrate the mucosa often leaves the needle tip in the deep wall. The needle is next withdrawn and fluid injected until a sharp lift (due to submucosal expansion) begins to form; the needle is then held steady and the injection finished. The initial injection may result in a subtle deep lift that resolves quickly. It was the authors' belief that only submucosal expansion could lead to a stable mucosal lift. A colonic ESD case in which a polyp was inadvertently resected via needle knife in an expanded subserosal plane led to a questioning of this position. This study's purpose was to determine if stable deep wall mucosal lifts can be generated via bowel wall injection.

Methods

Transmucosal and intramural injections into bovine large bowel were carried out. Stable lifts and lift cross sections were made and examined grossly and histologically to determine the location of the lift fluid. Clinical ESD videos were also reviewed.

Results

Over 200 intact and cross-sectioned lifts were assessed. Gross inspection revealed two types of lifts (superficial and deep), whereas cross sections and histologic analyses revealed examples of stable expansion of the submucosal, muscularis propria, and subserosal layers post injection. Clinical "deep" lifts were also found. Superficial lifts are more focal and taller, whereas deep wall lifts are broader and less prominent.

Conclusion

Stable deep wall mucosal lifts occur and are likely due to the deep starting point of the needle post insertion. If ESD/EMR are attempted with a deep lift, the chances of failure or perforation are high. Lifts must be carefully scrutinized before starting ESD/EMR. Other means of lift establishment should be evaluated and considered.

http://bit.ly/2TR9X3v

Near-infrared fluorescence laparoscopy of the ureter with three preclinical dyes in a pig model

Abstract

Background

Ureteric injury is reported to occur in 1–7.6% of colorectal surgeries. To reduce the incidence of ureteral injury, it is essential to identify the ureters. The use of near-infrared fluorescence (NIRF) imaging with intravenously administered dyes might be of added value for ureteral visualization during laparoscopy. The aim of this study is to assess the performance of three preclinical dyes; IRDye^® 800BK, IRDye^® 800NOS and IRDye^® 800CW, for near-infrared fluorescence laparoscopy of the ureter in pigs.

Methods

In three female Dutch landrace pigs, the new dyes were evaluated. In each pig, 1 dye was tested using a 6-mg intravenous dose in a concentration of 1 mg/ml. Imaging was performed in fluorescence mode and white light mode with a laparoscopic imaging system. In order to further evaluate the dyes, an ex vivo imaging experiment was performed, in which 8 decreasing concentrations per dye, diluted in PBS, were evaluated in a transparent test tube with NIRF mode at a distance of 1, 5 and 10 cm from the laparoscope.

Results

All three dyes were effective in allowing the identification of the ureter with NIRF imaging. The ureter became fluorescent after 35, 45 and 10 min, respectively, for IRDye^® 800BK, IRDye^® 800NOS and IRDye^® 800CW with a maximum target-to-background ratio (TBR) of 2.14, 0.66 and 1.44, respectively. In the ex vivo imaging experiment, all three dyes produced a strong fluorescence signal at all concentrations and all distances evaluated.

Conclusions

Intravenous administration of the preclinical dyes IRDye^® 800CW, IRDye^® 800 BK and IRDye^® 800NOS facilitated successful identification of the anatomical course of the ureter in living pig models. The highest measured TBR occurred with the use of IRDye^® 800BK. Ex vivo, a correlation was observed between the fluorescence intensities of the signal with the concentration of the dye and with the distance to the object.

http://bit.ly/2BDo2KS

Developing minimally invasive procedure quality metrics: one step at a time

Abstract

Background

Despite extensive first-hand surgical experience, rank and file members of surgical societies are generally not trained in and have not therefore been included in surgical quality measure development. The purpose of this exercise was to determine if a structured quality metric design tool could bridge this gap, facilitating rapid development of focused quality metrics by minimally invasive surgeon attendees of the April 2018 SAGES Annual Meeting.

Methods

Expert minimally invasive surgeons attended a 90-min workshop with didactic and interactive quality metric design sessions during the Annual Meeting. The interactive portion was formed around a novel structured quality measure development tool that graded presenting symptoms, short-term complications, and long-term disutility of care.

Results

For first-time symptomatic inguinal hernia repair, first-time small to moderate size ventral hernia repair, and elective laparoscopic cholecystectomy, each workgroup was able to develop one quality, one short-term complication, and one long-term disutility metric.

Conclusions

A structured quality metric design tool facilitates application of knowledge through rapid development of multifaceted, patient-centric outcomes measures by expert minimally invasive surgeons, otherwise not formally trained in metric development. The exercise also highlighted the need to rigorously define denominator populations and to guard against metric-driven undertreatment.

http://bit.ly/2TTStUc

A minimally invasive approach for peritonectomy procedures and hyperthermic intraperitoneal chemotherapy (HIPEC) in limited peritoneal carcinomatosis: The American Society of Peritoneal Surface Malignancies (ASPSM) multi-institution analysis

Abstract

Background

Minimally invasive surgery is playing an increasing role in the treatment of patients with gastrointestinal and gynaecological malignancies as the data show reduced morbidity, faster recovery and similar oncological outcome when compared to open procedures.

Materials and methods

The American Society of Peritoneal Surface Malignancies (ASPSM) conducted a retrospective study to analyse peritonectomy procedures and HIPEC done via the laparoscopic route. A database with standard clinical and pathological parameters was set up and distributed amongst ASPSM members. Rate of relapse, morbidity and mortality were the primary endpoints of the study.

Results

A total of 90 patients from 7 centres around the world were identified. Sixty percent were female. Mean age was 50 years. Peritoneal carcinomatosis from appendiceal origin was the most common diagnosis in a 64.9% of patients and colon origin was diagnosed in 16.5% of patients. Mean peritoneal cancer index (PCI) was 4.1 (0–10). Forty-one percent of patients had a bowel resection. Mean operative time was 4.7 h (2.5–8). All patients had a complete cytoreduction and HIPEC. Grade 3 and 4 morbidity was 3.0 and 6.5%, respectively. The most common reason for re-operation was an internal hernia in 2 out of 5 cases. Operative mortality and re-admission rates were 0 and 5%, respectively. Mean hospital stay was 7.4 days (1–18). At a mean follow-up of 31.6 months, 15/90 patients have a disease relapse but loco-regional relapse was identified in only five patients.

Conclusions

Analysis of these data suggests that minimally invasive approach for peritonectomy procedures and HIPEC is feasible, safe and should be considered as part of the armamentarium for highly selected patients with peritoneal surface malignancies with limited tumour burden, defined as PCI of 10 or less and borderline tumours as low-grade pseudomyxoma and benign multicystic mesothelioma.

http://bit.ly/2BO1U0D

Laparoscopic pyloroplasty versus endoscopic per-oral pyloromyotomy for the treatment of gastroparesis

Abstract

Background

Gastroparesis is a debilitating functional disorder of the stomach characterized by delayed gastric emptying absent an obstructive etiology. Surgical or endoscopic disruption of the pylorus has been utilized to treat this disease, but there is little evidence comparing laparoscopic pyloroplasty (LP) with endoscopic per-oral pyloromyotomy (POP). Herein we describe our experience at our institution using a propensity-matched cohort study to compare outcomes between these procedures.

Methods

All patients who underwent LP for the treatment of gastroparesis from October 2014 through September 2017 at our institution were retrospectively reviewed. Propensity scoring was used to match these patients 1:1 to patients undergoing POP during this time period based on gender, age, and etiology of gastroparesis. Symptom scores using the Gastroparesis Cardinal Symptom Index (GCSI), scintigraphic gastric emptying studies (GES), and perioperative outcomes were compared between matched cohorts. Thirty patients underwent LP for gastroparesis during the study period which were matched 1:1 with patients undergoing POP. The etiology of gastroparesis was 63.3% idiopathic (n = 19), 20.0% post-surgical (n = 6), and 16.7% diabetic (n = 5) in both cohorts.

Results

Patients who underwent LP had a longer average length of stay (4.6 vs. 1.4 days, p = 0.003), operative time (99.3 vs. 33.9 min, p < 0.001), and estimated blood loss (12.9 vs. 0.4 mL, p < 0.001). There were more complications in the LP cohort (16.7 vs. 3.3%, p = 0.086), which included surgical site infection (6.7 vs. 0%, p = 0.153), pneumonia (6.7 vs. 0.0%, p = 0.153), and unplanned ICU admission (10.0 vs. 0.0%, p = 0.078). LP and POP both resulted in similar, significant improvements in both in GCSI scores and objective gastric emptying.

Conclusions

Per-oral endoscopic pyloromyotomy (POP) is safe and effective for the treatment of medical refractory gastroparesis. POP has less perioperative morbidity compared to LP with comparative functional outcomes.

http://bit.ly/2TNp2Dm

Predicting venous thromboembolism following laparoscopic bariatric surgery: development of the BariClot tool using the MBSAQIP database

Abstract

Background

Bariatric surgery is an effective treatment for severe obesity; however, postoperative venous thromboembolism (VTE) remains a leading cause of morbidity and mortality. The objective of this study is to develop a tool to stratify individuals undergoing laparoscopic bariatric surgery according to their 30-day VTE risk.

Methods

This is a retrospective cohort study of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database. This registry collects data specific for metabolic or bariatric surgery with 30-day outcomes from 791 centers. Individuals undergoing primary laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) were included. Characteristics associated with 30-day VTE were identified using univariate and multivariable analyses. A predictive model, BariClot, was derived from a randomly-generated derivation cohort using a forward selection algorithm. BariClot's robustness was tested against a validation cohort of subjects not included in the derivation cohort. The calibration and discrimination of two previously published VTE risk tools were assessed in the MBSAQIP population and compared to BariClot.

Results

A total of 274,221 patients underwent LRYGB or LSG. Overall, 1106 (0.4%) patients developed VTE, 452 (0.2%) developed pulmonary embolism, and 43 (0.02%) died due to VTE. VTE was the most commonly identified cause of 30-day mortality. A prediction model to assess for risk of VTE, BariClot, was derived and validated. BariClot consists of history of VTE, operative time, race, and functional status. It stratifies individuals into very high (> 2%), high (1–2%), medium (0.3–1%), and low risk groups (< 0.3%). This model accurately predicted events in the validation cohort and outperformed previously published scoring systems.

Conclusions

BariClot is a predictive tool that stratifies individuals undergoing bariatric surgery based on 30-day VTE risk. Stratifying low- and high-risk populations for VTE allows for informed clinical decision-making and potentially enables further research on customized prophylactic measures for low- and high-risk populations.

http://bit.ly/2BBUlKg