Neuroradiology

Anterior ischemic stroke: Comparison of two clinical outcome prediction scores through the investigation of cerebral collaterals using multiphase CT angiography Publication date: Available online 12 April 2019 Source: Journal of Neuroradiology Author(s): A. Nigron, N. Bourgois, S. Dao, C. Lambert, M. Perrier, S. Akono, R. Moreno, E. Chabert, B. Jean, B. Claise, L. Gerbaud, L. Boyer, A. Zerroug Summary Purpose: To compare the evaluation of collaterals on multiphase computed tomography (CT) angiography using the score proposed by the reference study by Menon BK et al. and the Alberta Stroke Program Early CT (ASPECT) score for the prediction of favorable clinical outcome in patients with anterior ischemic stroke (IS). Materials and Methods: Retrospective single center study including 199 patients with anterior ischemic stroke and evaluated using multiphase CT angiography. Collaterals were assessed using the reference score and ASPECT score. The early clinical outcome (National Institute of Health Stroke Score (NIHSS) over day 1) and later clinical outcome (90-day modified Rankin Scale (mRS)) were collected. The primary analysis related to the association between collateral scores and clinical outcome. Results: Collaterals are an independent predictive factor of favorable clinical outcome with the two scores, ranging from an odds ratio (OR) [95% confidence interval (CI)] = 1.84 [1.23; 2.76], p = 0.003 for the reference score to an OR [95% CI] = 2.63 [1.21; 5.73], p = 0.015 for the phase 3 ASPECT score. The phase 3 ASPECT score offers better sensitivity (Se) for the prediction of a favorable clinical outcome (Se = 95%, specificity (Sp) = 37% for a threshold of 7/7) than the reference score (Se = 83%, Sp = 47% for a threshold of 4/5). Conclusion: This study demonstrates the value of the ASPECT score in analyzing collaterals using multiphase CT angiography for the prediction of clinical outcome.

Fusion Imaging of Time Resolved Imaging of Contrast KineticS (TRICKS) and High Resolution Volumetric T2 MR Sequences in the Evaluation of Spinal Vascular Malformations Publication date: Available online 11 April 2019 Source: Journal of Neuroradiology Author(s): Satyanaryana Mandalapu, Santhosh Kannath, Chandrasekharan Kesavadas

Number of Stentriever Passes and Outcome after Thrombectomy in Stroke Publication date: Available online 11 April 2019 Source: Journal of Neuroradiology Author(s): Rawan Kharouba, Pavel Gavriliuc, Nour Eddine Yaghmour, John M. Gomori, Jose E. Cohen, Ronen R. Leker Abstract Background and Purposes: Stroke secondary to emergent large vessel occlusions (ELVO) involving the anterior circulation can be treated with intravenous tissue plasminogen activator (IV-tPA) or thrombectomy. Data regarding the influence of the number of stentriever passes needed for vessel recanalization on outcome is lacking. Patients and Methods: We prospectively accrued data on consecutive patients with ELVO that were treated with thrombectomy. Procedural details including the number of stentriever passes needed to achieve vessel recanalization and clot length were collected. Functional outcome was determined with the modified Rankin Scale (mRS) at 90 days post stroke with mRS≤2 considered favorable outcome. Data on demographics, risk factors, stroke severity, survival, and occurrence of symptomatic intracranial hemorrhage (sICH) was also collected. Results:On univariate analysis more than one pass needed to achieve recanalization impacted survival and functional outcome after 90 days as did age, stroke severity and collateral and reperfusion status. On multivariate logistic regression the number of passes needed to achieve revascularization (OR 10.0, 95%CI 2.28–43.94, p = 0.002), age (OR 0.90, 95%CI 0.84–0.96, p = 0.001) and collateral status (OR 7.90, 95%CI 1.87–33.35, p = 0.005) remained significant modifiers for favorable outcome. On logistic regression the only variable associated with the need to perform more than a single stentriever pass was time from symptom onset to target vessel recanalization (OR 1.007 955 CI 1.002-1.012). Conclusions:The number of passes needed to achieve target vessel recanalization modifies outcome after thrombectomy and successful recanalization after a single pass is associated with favorable outcome.

Force and Aspiration on Catheters Utilized in the ADAPT Technique in Acute Ischemic Stroke: A Bench Top Analysis Publication date: Available online 11 April 2019 Source: Journal of Neuroradiology Author(s): Mickey Smith, Jonathan Pace, Connie Ju, Yin C. Hu Abstract INTRODUCTION: Given the high morbidity and mortality of stroke, there remains a demand for techniques that provide rapid and safe intervention while improving time to recanalization. The direct aspiration first-pass technique (ADAPT) uses force and aspiration for clot removal without the aid of separators or retrievers. In this study, we compare the force and aspiration qualities of commercially available catheters. METHODS: Four different catheters with varying inner diameters were set up in a bench top model to test catheter tip pressure and flow rate. Catheter tip pressure was measured by attaching the catheter to a vacuum pressure gauge and an aspiration pump. The flow rate was calculated by measuring the volume of room temperature water aspirated through each catheter over a given time. RESULTS: The Microvention Sofia catheter generated the greatest tip force (21.32 g), and the Stryker AXS Catalyst 6 catheter generated the smallest tip force (15.88 g). The Penumbra ACE 068 catheter and Medtronic ARC catheter measured 20.87 g and 16.78 g respectively. The ACE 068 had highest rate of aspiration at 289 mL/min, and the Catalyst 6 catheter had the lowest rate at 214. The Microvention Sofia catheter had the second highest rate while the ARC had the third highest rate, measuring 285 ml/min and 256 mL/min, respectively. CONCLUSIONS: When using the ADAPT technique, knowledge of the tip force and catheter flow rate of newer catheters with larger distal inner diameters may guide selection of aspiration catheters. While this study demonstrates differences in tip force and flow rate of different commercially available catheters, clinical translation will require further testing and evaluation.

Aquaporin 4 distribution in the brain and its relevance for the radiological appearance of neuromyelitis optica spectrum disease Publication date: Available online 11 April 2019 Source: Journal of Neuroradiology Author(s): Roxana Ameli, Charles R.G.Guttmann, Juan Carlos Prieto, Fabien Rollot, Miklos Palotai, Sandra Vukusic, Romain Marignier, François Cotton, Group Members for OFSEP Imaging Working, COPIL of OFSEP, the NOMADMUS study group. Abstract Background and Purpose: To determine the precise incidence of lesions at sites of high Aquaporin-4 expression (hAQP4) and their possible association with known neuromyelitis optica spectrum disease (NMOSD) lesions patterns. Materials and methods: A retrospective analysis of brain and, when available, spinal cord MRI scans of 54 NMOSD patients recruited among the French NMOSD cohort was performed. Brain lesions were annotated as MS-like, non-specific, or evocative of NMOSD. The topography of hAQP4 was reassessed by human brain atlas. The incidence of lesions in hAQP4 and their association with lesions evocative of NMOSD was estimated. Results:Among those included (41/54 female, mean age:45 years) 47/54(87%) presented brain lesions. Twenty-six/47(55%) had lesions in hAQP4. Thirty-two/54 patients(60%) had lesions considered evocative of NMOSD. The majority of them also presented lesions in hAQP4 (65%, 21/32). Patients with lesions in hAQP4 and lesions evocative of NMOSD demonstrated more extensive myelitis compared to the other patients (7[6–10] versus 4[3–5] vertebral segments, P = 0.009). Conclusion:The coexistence of lesions evocative of NMOSD and in hAQP4 is associated with significantly more extensive myelitis, and might have pathophysiological and clinical significance.

Differences in cortical perfusion detected by arterial spin labeling in nonamnestic and amnestic subtypes of early-onset Alzheimer's disease Publication date: Available online 11 April 2019 Source: Journal of Neuroradiology Author(s): Verclytte Sebastien, Lopes Renaud, Viard Romain, Rollin Adeline, Vanhoutte Matthieu, Pasquier Florence, Pruvo Jean-Pierre, Leclerc Xavier Abstract Objectives: Early-onset Alzheimer's disease (EOAD) begins before the age of 65 and is characterized by a faster clinical course and the frequency of nonamnestic symptoms compared to late onset Alzheimer disease (LOAD). However, the pathophysiological process of EOAD remains unclear. We expected that ASL may show widespread cortical hypoperfusion in EOAD compared to LOAD and in nonamnestic EOAD compared to amnestic EOAD. Methods: In this study, 26 EOAD patients (16 amnestic and 10 nonamnestic patients), 29 LOAD patients and 12 healthy controls underwent pseudo-continuous ASL and 3D FFE T1 sequences. Statistical comparisons between EOAD, LOAD and control groups were made after surface-based analysis of CBF maps in regressing out the cortical thickness. Results: ASL showed a more severe hypoperfusion in nonamnestic EOAD patients compared to amnestic EOAD ones, with mean CBF values (±std) of 26.9 (±3.8) and 46.6 (±24.1) ml/100 g/min respectively (p = 0.014), located in the bilateral temporo-parietal neocortex, the precuneus, the posterior cingulate cortices (PCC) and frontal lobes. Comparison between EOAD and LOAD patients showed a trend to hypoperfusion in the left parietal lobe, PCC and precuneus in EOAD (p < 0.001 uncorrected). Conclusions: Different patterns of hypoperfusion between nonamnestic and amnestic EOAD subtypes were identified, with a more severe and extensive hypoperfusion in nonamnestic patients. A trend towards more severe hypoperfusion was detected in EOAD compared to LOAD. Further studies are needed to validate ASL as a potential tool for the distinction of EOAD subtypes and the prediction of the time course of the disease.

WEB-assisted microwire navigation for the treatment of complex wide-neck intracranial aneurysms: Technical note Publication date: Available online 5 April 2019 Source: Journal of Neuroradiology Author(s): Federico Cagnazzo, Cyril Dargazanli, Pierre-Henri Lefevre, Gregory Gascou, Imad Derraz, Carlos Riquelme, Alain Bonafe, Vincent Costalat Abstract Background Unfavorable aneurysm anatomy can make microwire navigation challenging, increasing the risk of complications. We present our experience of WEB-assisted microcatheterization in complex aneurysms. Clinical presentation Flow diversion was performed for three wide-neck large/giant intracranial aneurysms. A WEB was placed inside the sac, blocking the aneurysm neck and providing a contact surface to redirect the microwire across the aneurysm. Conclusion WEB-assisted microcatheterization appears an alternative strategy for the treatment of complex aneurysms.

Carotid artery imaging: the study of intra-plaque vascularization and hemorrhage in the era of the "vulnerable" plaque Publication date: Available online 4 April 2019 Source: Journal of Neuroradiology Author(s): Michele Porcu, Michele Anzidei, Jasjit S. Suri, Bruce A Wasserman, Nicoletta Anzalone, Pierleone Lucatelli, Federico Loi, Roberto Montisci, Roberto Sanfilippo, Vasileios Rafailidis, Luca Saba Abstract Intraplaque hemorrhage (IPH) is one of the main factors involved in atherosclerotic plaque (AP) instability. Its recognition is crucial for the correct staging and management of patients with carotid artery plaques to limit ischemic stroke. Imaging plays a crucial role in identifying IPH, even if the great variability of intraplaque vascularization and the limitations of our current imaging technologies make it difficult. The intent of this review is to give a general overview of the main features of intraplaque vascularization and IPH on Ultrasound (US), Computed Tomography (CT), Magnetic Resonance (MR) and Nuclear Medicine, and a brief description on the future prospectives.

Comparison between postmortem computed tomography and autopsy in the detection of traumatic head injuries Publication date: Available online 4 April 2019 Source: Journal of Neuroradiology Author(s): L. Legrand, T. Delabarde, R. Souillard-Scemama, I. Sec, I. Plu, J-M. Laborie, Y. Delannoy, L. Hamza, M. Taccoen, L. De Jong, J. Benzakoun, M. Edjlali, J-F. Méder, C. Oppenheim, B. Ludes Abstract Introduction. – The aim of this study was to assess the agreement between postmortem computed tomography (PMCT) and autopsy in detecting traumatic head injuries. Materials and Methods. – Consecutive cases of death that underwent both unenhanced PMCT and conventional autopsy were collected from our institution database during a period of 3 years and reviewed retrospectively. PMCT images were reviewed for the presence of fractures (cranial vault, skull base, facial bones and atlas/axis) and intracranial hemorrhage. Kappa values were calculated to determine the agreement between PMCT and autopsy reports. Results. – 73 cases were included, of which 44 (60%) had head trauma. Agreement between PMCT and autopsy was almost perfect (κ = 0.95) for fractures and substantial (κ = 0.75) for intracranial hemorrhage. PMCT was superior to autopsy in detecting facial bone and upper cervical spine fractures, and intraventricular hemorrhage. However, in some cases thin extra-axial blood collections were missed on PMCT. Conclusions. – The agreement between PMCT and autopsy in detecting traumatic head injuries was good. Using a combination of both techniques increases the quality of postmortem evaluation because more lesions are detected.

Efficacy of post-dilatation during carotid artery stenting for unstable plaque using closed-cell design stent evaluated by optical coherence tomography Publication date: Available online 4 April 2019 Source: Journal of Neuroradiology Author(s): Kei Harada, Masahito Kajihara, Yukihiro Sankoda, Syunsuke Taniguchi Abstract Background and Purpose: This study aimed to use optical coherence tomography (OCT) to evaluate the efficacy of post-dilatation (PD) after stent placement for unstable plaques during carotid artery stenting (CAS) using closed-cell design stent. Materials and Methods: Twelve unstable carotid plaque lesions diagnosed by magnetic resonance imaging were evaluated by OCT during CAS. Pre-procedural minimum lumen diameter and area were 1.5 ± 0.6 mm and 2.6 ± 1.6 mm2, respectively. The lesion was pre-dilated with balloon catheters (diameter 4.8 ± 0.3 mm), and closed-cell stent was deployed. PD was performed with balloon catheters of the same size as those used for pre-dilatation. Minimum lumen diameter/area and in-stent tissue prolapse volume after stent placement and after PD were calculated by 2-dimensional cross section images. The number of the stent cells showing tissue prolapse and malapposition after stent-placement and after PD were calculated by 3-dimensional analysis. Results: Compared to after stent placement, in-stent tissue prolapse volume (0.18 ± 0.10 to 0.22 ± 0.07 mm2/slice, p < 0.01), number of stent cells with any tissue prolapse (12.7 ± 8.2 to 21.0 ± 11.8%, p < 0.001) were significantly increased after PD; stent cells with ≥500-µm tissue prolapse (1.6 ± 1.1 to 0.7 ± 0.8%, p < 0.01) and stent malapposition (17.4 ± 7.2 to 14.0 ± 6.3%, p < 0.01) were significantly decreased. Conclusions: PD after carotid stent placement caused increase in in-stent tissue prolapse volume and small tissue prolapse, however, the in-stent large tissue prolapse decreased, as the in-stent tissue prolapse may have been crushed into debris.