Shahid, Adnan Hussain

Background Non-acute or chronic subdural hematoma (cSDH) is commonly treated with surgical evacuation followed by middle meningeal artery embolization (MMAe). This two step approach increases procedural complexity and redundancy, hospitalization duration, and patient risk. We hypothesized that cSDH could be managed through a single session endovascular procedure and conducted a multimodal preclinical study to evaluate feasibility. Methods We performed three-dimensional heat mapping of hematoma distribution from preoperative CT scans (n=69) and analyzed middle meningeal artery (MMA) and superior sagittal sinus (SSS) anatomy and perforation trajectories using imaging from 107 patients. Rheological properties of 41 SDH samples were assessed using hybrid rheometry and modeled with the Carreau equation. Aspiration feasibility was tested using a 0.027 inch microcatheter (n=16), and dura perforation forces were quantified with a 28 G needle in fresh cadaveric dura (n=10). Results Heat mapping localized cSDH to the parietal convexities (>80% probability) under the branches of the MMA, with limited midline involvement and proximity to the SSS (<10%). The posterior division of the MMA (diameter 1.23±0.23 mm) accommodated a 0.027 inch microcatheter in >90% of cases, with perforation trajectories targeting high probability hematoma zones in 105 of 107 cases. SDH samples exhibited shear thinning viscosity ( η ₀ =172 mPa×s, η ∞ =2.78 mPa×s), with mean aspiration times of 1.21±0.54 min per 10 mL. Perforation forces averaged 0.68±0.24 N in normal and 1.29±0.48 N in calcified dura (P=0.05). Conclusion Anatomical, rheological, and biomechanical data from this study support the feasibility of endovascular drainage of cSDH through the MMA.

Background: Little is known about the association between intraplaque hemorrhage (IPH) and other features of high-risk carotid atherosclerotic plaques, such as the presence of plaque ulceration, plaque enhancement, and lipid-rich necrotic core (LRNC). This study set out to assess the relationship between IPH and other vulnerable plaque features. Materials and Methods: A retrospective review was done of 102 patients with IPH in one or both of the internal carotid arteries (ICA) on neck MRA between 1/1/2016 and 3/31/2021. IPH was defined as a ≥200% signal intensity of the adjacent sternocleidomastoid muscle on MPRAGE images. All ICA plaques were assessed for the presence or absence of IPH, plaque ulceration, plaque enhancement, and LRNC, as well as IPH volume. IPH volume was measured manually by outlining the region of interest. Results: A total of 102 patients were included, with 88 (86.3%) being male. The average age was 73.5 years (SD = 9.0). Both IPH and LRNC were more commonly seen in the left carotid artery ( p = .018 and p = .047, respectively). For right-sided ICAs, there was a significant association between IPH and LRNC ( p < .0001). Lesions without IPH were more likely to have plaque enhancement than lesions with IPH ( p = .04). For left-sided ICAs, there was also a significant association between the presence of IPH and LRNC ( p < .0001). Conclusions: There is a significant association between the presence of IPH and LRNC. An inverse relationship was found between the presence of IPH and plaque enhancement for right-sided plaques. No associations were found between IPH and plaque ulceration.

Objectives: The development and evaluation of percutaneous thrombectomy devices for pulmonary embolism (PE) pose a need for standardized large in vivo models with representative anatomical and physiological conditions and clots analogs. In this study, we present a swine model of PE model employing human-derived clot analogs. Material and Methods: Baseline angiographic and physiological pressure measurements were obtained in six adult Yorkshire pigs (45–65 kg) and results were benchmarked for interspecies comparison with published human data using fluoroscopic examinations, intra-arterial pressure measurements, and histologic studies. Then, clot analogs were created ex vivo employing banked human blood and a subset incubated in iodinated contrast for fluoroscopic visualization. Clot analogs were then embolized via a femoral venous access and angiographic/physiological consequences were evaluated. Results: The main, right, and left pulmonary artery diameters were 24 ± 1.1 mm, 16.5 ± 0.8 mm, and 12.6 ± 1.2 mm, respectively. The angle between the main pulmonary artery at the bifurcation point was approximately 90–95°. The clot analogs were heterogeneous and had increased fibrin content along the clot length. The overall composition was 96.63% red blood cell (RBC)/3.37% fibrin in the initial section, 48.85% RBC/51.15% fibrin in the intermediate section, and 3.44% RBC/96.56% fibrin in the final section. Embolization of the clot analogs resulted in distal occlusion of the right and left pulmonary arteries. Conclusions: This swine model coupled with clot analog is able to accurately mimic human anatomical and physiological conditions in PE making it feasible for the evaluation of pulmonary thrombectomy devices.

Background Although successful recanalization (modified Thrombolysis in Cerebral Infarction score 2b–3) can be achieved in >80% of patients experiencing stroke attributable to large‐vessel occlusion, up to 50% of patients may develop poor clinical outcomes (modified Rankin scale score at 90 days of 3–6), termed as futile recanalization (FR). The meta‐analysis aims to determine various risk factors associated with FR. Methods In February 2021, a comprehensive literature search on risk factors associated with FR was performed with keywords, including “stroke,” “thrombectomy,” “treatment outcome,” and “risk factors.” Their correlations with FR were evaluated using the random effect size meta‐analysis model. Results Twenty studies with 3037 patients were included with an FR rate of 51.0%. Our meta‐analyses showed that age (mean difference [MD], 5.6; 95% CI, 4.7–6.6), National Institutes of Health Stroke Scale score (MD, 4.2; 95% CI, 3.2–5.1), Alberta Stroke Program Early Computed Tomography (CT) Score (MD, −0.5; 95% CI, 0.8–0.3), hypertension (odds ratio [OR], 1.5; 95% CI, 1.3–1.9), systolic blood pressure (MD, 6.9; 95% CI, 3.6–8.7), atrial fibrillation (OR, 1.5; 95% CI, 1.2–1.8), IV tPA (tissue‐type plasminogen activator) (OR, 0.7; 95% CI, 0.5–0.8), puncture to recanalization time (MD, 9.6; 95% CI, 5.3–13.8), and time of onset to recanalization (MD, 32.1; 95% CI, 6.5–47.7) were significantly associated with FR ( P <0.001). Conclusions Age, admission National Institutes of Health Stroke Scale score, Alberta Stroke Program Early CT Score, comorbidities, including hypertension, systolic blood pressure, atrial fibrillation, and use of IV tPA, as well as time frames, including onset to recanalization and onset to arrival, were significant influencing factors for FR after mechanical thrombectomy. Future research on the mechanism underlying FR is warranted.

Background Headache in patients with moyamoya disease is an under-addressed topic in the medical literature. Delay in the diagnosis of moyamoya disease or inappropriate treatment of headache could lead to devastating cerebrovascular outcome. With the evolving understanding of moyamoya disease, migraine pathophysiology, and various migraine-specific medications that have become available, it is crucial to provide an updated overview on this topic. Methods We searched PubMed for keywords including moyamoya disease, moyamoya syndrome, headache in moyamoya, surgical revascularization, surgical bypass, migraine and moyamoya, and calcitonin gene-related peptide (CGRP). We summarized the literature and provide a comprehensive review of the headache presentation, possible mechanisms, the impact of various surgical revascularizations on headache in patients with moyamoya disease, and the medical management of headache incorporating novel migraine-specific treatments. Results and conclusion: The most common headache phenotype is migraine; tension-type headache, hemiplegic migraine, and cluster headache have also been reported. Most patients experience improvement of headache after surgical revascularization, though some patients report worsening, or new-onset headache after surgery. Given the complexity of moyamoya disease, careful consideration of different types of medical therapy for headache is necessary to improve the quality of life while not increasing the risk of adverse cerebrovascular events. More prospective studies are warranted to better understand and manage headache in patients with moyamoya disease.

Background and aim First pass effect (FPE) is defined as achieving a complete recanalization with a single thrombectomy device pass. Although clinically desired, FPE is reached in less than 30% of thrombectomy procedures. Multiple device passes are often necessary to achieve successful or complete recanalization. We performed a systematic review and meta-analysis to determine the recanalization rate after each pass of mechanical thrombectomy and its association with good neurological outcome. Methods A literature search was performed for studies reporting the number of device passes required for either successful (mTICI 2b or higher) or complete (mTICI 2c or higher) recanalization. Using random-effect meta-analysis, we evaluated the likelihood of recanalization and good neurological outcome (measured with the modified Rankin Score <2 at 90 days) after each device pass. Results Thirteen studies comprising 4197 patients were included. Among cases with failed first pass, 24% of them achieved final complete recanalization and 45% of them achieved final successful recanalization. Independently to the total number of previously failed attempts, the likelihood of achieving successful recanalization was 30% per pass, and the likelihood to achieve complete recanalization was about 20% per pass. The likelihood of good neurological outcome in patients with final successful recanalization decreased after each device pass: 55% after the first pass, 48% after the second pass, 42% after the third pass, 36% after the fourth pass, and 26% for 5 passes or more. Conclusion Each pass is associated with a stable likelihood of recanalization but a decreased likelihood of good neurological outcome.