Faculty Bibliography

Initially developed for large and giant wide-necked aneurysms of the internal carotid artery, flow diverter devices are now used in almost every location safely and with effectiveness.1-5 This video demonstrates a unique case of a giant aneurysm of the right petrous internal carotid artery in a 20-yr-old patient. This is an extremely rare location, and most of patients are asymptomatic.3-6 Signs of compression of the seventh and eight cranial nerves can be present and even Horner syndrome and lower cranial nerves neuropathies. Nevertheless, rupture can lead to epistaxis and otorrhagia, and ultimately to hemorrhagic shock. The patient in the current report was otherwise healthy but presented with lightheadedness and dizziness for 10 d. The patient consented to the procedure. There was no history of major trauma or head and neck infection. A transradial endovascular flow diversion embolization of a giant aneurysm of the petrous internal carotid artery is herein demonstrated in a stepwise manner. A triaxial system was used to deploy 3 overlapping devices. Concepts of J-wire technique, multiple coverage,1 and the so-called weld technique are emphasized. The role of adjunctive coiling and main reasons for failure are also discussed.7,8 Brief cases of flow diversion embolization of aneurysms of different morphologies at different locations are used to highlight the importance of assessing vessel wall apposition and follow-up imaging.

BACKGROUND AND IMPORTANCE/BACKGROUND:Spinal cord infarction is rare but can be extremely disabling. Prompt diagnosis and treatment of these infarcts is important for patient outcomes. While intravenous thrombolytic therapy is a well-established form of treatment in circumstances of cerebral stroke, it has only recently been successfully used in a few incidents of spinal cord ischemia. We present a case of anterior spinal artery (ASA) territory ischemia treated with ASA intra-arterial thrombolytic therapy. CLINICAL PRESENTATION/METHODS:A 52-year-old male presented with acute onset of severe lumbar pain, rapidly progressing paraplegia and loss of pain and temperature sensation, with preservation of proprioception and vibratory sensation at the L1 level and below on the right and at the L3 level and below on the left. MRI showed restricted diffusion involving the cord at and below L1 level, with normal cord T2 signal. Digital subtraction spinal angiography showed ASA cutoff in the descending limb at the level of L1. Intra-arterial tissue plasminogen activator (t-PA) combined with verapamil and eptifibatide was administered within the ASA and the patient had significant neurological improvement immediately postoperatively and at 8-month clinical follow-up. CONCLUSION/CONCLUSIONS:Direct ASA intra-arterial thrombolysis is feasible, and this drug combination might be an effective therapy for spinal stroke.

INTRODUCTION/BACKGROUND:The carotid web is a compelling potential mechanism of embolic ischemic stroke. In this study, we aim to determine the prevalence of ipsilateral carotid web in a cohort of ischemic stroke patients and to perform a systematic review and meta-analysis of similar cohorts. PATIENTS & METHODS/METHODS:We performed a retrospective, observational, cohort study of acute ischemic stroke patients admitted to a comprehensive stroke center from June 2012 to September 2017. Carotid web was defined on computed tomography angiography (CTA) as a thin shelf of non-calcified tissue immediately distal to the carotid bifurcation. We described the prevalence of carotid artery webs in our cohort, then performed a systematic review and meta-analysis of similar cohorts in the published literature. RESULTS:We identified 1,435 potentially eligible patients of whom 879 met criteria for inclusion in our analysis. An ipsilateral carotid web was detected in 4 out of 879 (0.45%) patients, of which 4/4 (1.6%) were in 244 patients with cryptogenic stroke and 3/4 were in 66 (4.5%) patients <60 years old with cryptogenic stroke. Our systematic review yielded 3,192 patients. On meta-analysis, the pooled prevalence of ipsilateral carotid web in cryptogenic stroke patients <60 was 13% (95% CI: 7%-22%; I2 = 66.1%). The relative risk (RR) of ipsilateral versus contralateral carotid web in all patients was 2.5 (95% CI 1.5-4.2, p = 0.0009) whereas in patients less than 60 with cryptogenic stroke it was 3.0 (95% CI 1.6-5.8, p = 0.0011). DISCUSSION/CONCLUSIONS:Carotid webs are more common in young patients with cryptogenic stroke than in other stroke subtypes. Future studies concerning the diagnosis and secondary prevention of stroke associated with carotid web should focus on this population.

The carotid web is a proposed stroke mechanism that may underlie cryptogenic stroke, particularly in younger patients without vascular risk factors. The web appears as a shelf-like projection into the lumen of the proximal cervical internal carotid artery without evidence of calcification. It is pathologically defined as intimal fibromuscular dysplasia. Altered haemodynamics distal to the web cause flow stagnation and remote embolisation of fibrin-based clots. It is best demonstrated and diagnosed on CT angiography (CTA) of the neck because of its ability to resolve calcium and create multiplanar reconstructions. Although they can be readily visualised on CTA, carotid webs may be missed or misinterpreted because they do not typically cause haemodynamically significant stenosis and can mimic arterial dissection, non-calcified atherosclerotic plaque and intraluminal thrombus. Options for management include antiplatelet therapy, carotid endarterectomy and carotid artery stenting. Modern management strategies for cryptogenic stroke include long-term cardiac monitoring, further investigation for structural cardiac disease and a diagnostic workup for arterial hypercoagulability, however, these strategies are not likely to capture the possibility of a carotid web. Carotid webs should be suspected in a young patient presenting with recurrent unihemispheric strokes particularly when conventional vascular risk factors are not present.

BACKGROUND:Attainment of basic microsurgical skills in neurosurgery presents a departmental challenge worldwide. Models for teaching are either not readily available or expensive, and are incompatible with a resident's busy schedule, requiring lengthy and proper setup. OBJECTIVE:Presenting a model and a set of measurable tasks, based upon a fruit (orange) which is cheap, easy to setup instantly when desired and can be used for training of basic microsurgical skills. METHODS:Basic microsurgical skills were identified necessitating hand-eye coordination working with the microscope. The goal was to dissect an orange segment, while preserving adjacent segments. Assessment was based on the number of side tears and task completion duration. Task was repeated in sequential manner (N=10), for validation purposes, for 3 operators at different seniority levels. RESULTS:trial, p<0.01), as well as duration of time required for task completion (mean initial duration of 28:16+-19:00 minutes to a duration of 16:33+-10:50 minutes in the last attempt ,p<0.01)was observed. Daily practice scores and time gradually improved, and seniority level of operators was correlated with scoring between individuals. CONCLUSION/CONCLUSIONS:The orange model is an easily accessible, cheap model enables the acquisition of basic micro-neurosurgical skills. In this work, we validated and defined reproducible tasks that can be scored and tracked, correlated with operator's proficiency and experience. This model can be incorporated into a resident's workflow environment and provides a platform for attainment of elementary microsurgical skills for neurosurgical residents.

BACKGROUND AND PURPOSE/OBJECTIVE:Mechanical thrombectomy (MT) has helped many patients achieve functional independence. The effect of time-to-treatment based in specific epochs and as related to Alberta Stroke Program Early CT Score (ASPECTS) has not been established. The goal of the study was to evaluate the association between last known normal (LKN)-to-puncture time and good functional outcome. METHODS:We conducted a retrospective cohort study of prospectively collected acute ischemic stroke patients undergoing MT for large vessel occlusion. We used binary logistic regression models adjusted for age, Modified Treatment in Cerebral Ischemia score, initial National Institutes of Health Stroke Scale, and noncontrast CT ASPECTS to assess the association between LKN-to-puncture time and favorable outcome defined as Modified Rankin Score 0-2 on discharge. RESULTS:Among 421 patients, 328 were included in analysis. Increased LKN-to-puncture time was associated with decreased probability of good functional outcome (adjusted odds ratio [aOR] ratio per 15-minute delay = .98; 95% confidence interval [CI], .97-.99; P = .001). This was especially true when LKN-puncture time was 0-6 hours (aOR per 15-minute delay = .94; 95% CI, .89-.99; P = .05) or ASPECTS 8-10 (aOR = .98; 95% CI, .97-.99; P = .002) as opposed to when LKN-puncture time was 6-24 hours (aOR per 15-minute delay = .99; 95% CI, .97-1.00; P = .16) and ASPECTS <8 (aOR = .98; 95% CI, .93-1.03; P = .37). CONCLUSION/CONCLUSIONS:Decreased LKN-groin puncture time improves outcome particularly in those with good ASPECTS presenting within 6 hours. Strategies to decrease reperfusion times should be investigated, particularly in those in the early time window and with good ASPECTS.

BACKGROUND AND PURPOSE/OBJECTIVE:The coronavirus disease-2019 (COVID-19) pandemic caused unprecedented demand and burden on emergency health care services in New York City. We aim to describe our experience providing acute stroke care at a comprehensive stroke center (CSC) and the impact of the pandemic on the quality of care for patients presenting with acute ischemic stroke (AIS). METHODS:We retrospectively analyzed data from a quality improvement registry of consecutive AIS patients at New York University Langone Health's CSC between 06/01/2019-05/15/2020. During the early stages of the pandemic, the acute stroke process was modified to incorporate COVID-19 screening, testing, and other precautionary measures. We compared stroke quality metrics including treatment times and discharge outcomes of AIS patients during the pandemic (03/012020-05/152020) compared with a historical pre-pandemic group (6/1/2019-2/29/2020). RESULTS:A total of 754 patients (pandemic-120; pre-pandemic-634) were admitted with a principal diagnosis of AIS; 198 (26.3%) received alteplase and/or mechanical thrombectomy. Despite longer median door to head CT times (16 vs 12 minutes; p = 0.05) and a trend towards longer door to groin puncture times (79.5 vs. 71 min, p = 0.06), the time to alteplase administration (36 vs 35 min; p = 0.83), door to reperfusion times (103 vs 97 min, p = 0.18) and defect-free care (95.2% vs 94.7%; p = 0.84) were similar in the pandemic and pre-pandemic groups. Successful recanalization rates (TICI≥2b) were also similar (82.6% vs. 86.7%, p = 0.48). After adjusting for stroke severity, age and a prior history of transient ischemic attack/stroke, pandemic patients had increased discharge mortality (adjusted OR 2.90 95% CI 1.77 - 7.17, p = 0.021) CONCLUSION: Despite unprecedented demands on emergency healthcare services, early multidisciplinary efforts to adapt the acute stroke treatment process resulted in keeping the stroke quality time metrics close to pre-pandemic levels. Future studies will be needed with a larger cohort comparing discharge and long-term outcomes between pre-pandemic and pandemic AIS patients.

OBJECTIVE:The carotid web (CW) is an underrecognized source of cryptogenic, embolic stroke in patients younger than 55 years of age, with up to 37% of these patients found to have CW on angiography. Currently, there are little data detailing the best treatment practices to reduce the risk of recurrent stroke in these patients. The authors describe their institutional surgical experience with patients treated via carotid endarterectomy (CEA) for a symptomatic internal carotid artery web. METHODS:A retrospective, observational cohort study was performed including all patients presenting to the authors' institution with CW. All patients who were screened underwent either carotid artery stenting (CAS) or CEA after presentation with ischemic stroke from January 2019 to February 2020. From this sample, patients with suggestive radiological features and pathologically confirmed CW who underwent CEA were identified. Patient demographics, medical histories, radiological images, surgical results, and clinical outcomes were collected and described using descriptive statistics. RESULTS:A total of 45 patients with symptomatic carotid lesions were treated at the authors' institution during the time period. Twenty patients underwent CAS, 1 of them for a CW. Twenty-five patients were treated via CEA, and of these, 6 presented with ischemic strokes ipsilateral to CWs, including 3 patients who presented with recurrent strokes. The mean patient age was 55 ± 12.6 years and 5 of 6 were women. CT angiography or digital subtraction angiography demonstrated the presence of CWs ipsilateral to the stroke in all patients. All patients underwent resection of CWs using CEA. There were no permanent procedural complications and no patients had stroke recurrence following intervention at the latest follow-up (mean 6.1 ± 4 months). One patient developed mild tongue deviation most likely related to retraction, with complete recovery at follow-up. CONCLUSIONS:CEA is a safe and feasible treatment for symptomatic carotid webs and should be considered a viable alternative to CAS in this patient population.

We present a patient who was diagnosed 20 yr prior to current presentation with a spinal arteriovenous malformation. This patient had a 10-yr history of worsening back pain (and underwent lumbar fusion), urinary dysfunction leading to 3-yr dependence on intermittent catheterization, lower extremity paresthesias and pain, and progressive weakness with multiple falls, leading to walker then wheelchair dependence for mobility. Magnetic resonance studies showed extensive thoracic cord expansion and edema with enlarged spinal cord surface veins and flow voids extending from spinal levels T6 to the conus medullaris. Partial embolization at an outside institution elicited transient symptom improvement. Repeated spinal angiogram demonstrated persistent T10 pial arteriovenous fistula (AVF) supplied by the posterior spinal artery arising from the right T11 segmental artery as well as by the anterior spinal artery from the left T10 segmental artery. Because additional embolization carried significant risk, we planned open surgery with fistula resection. Informed consent for the surgery and video recording was obtained. The patient was placed in the prone position, and a radial artery access was obtained for intraoperative angiogram. Following a posterior T9-T11 laminectomy and dural opening, a pial dissection was performed to expose the AVF. Intraoperative indocyanine green angiography was used to assist in identifying the feeders and major drainage of the AVF. Post-AVF resection, a formal intraoperative radial access spinal angiogram demonstrated complete resection of the lesion with no residual shunt or early venous drainage. The patient improved significantly and, on last follow-up, is ambulating without any assistive devices.

Our perspective on anatomy frequently depends on how this anatomy is utilized in clinical practice, and by which methods knowledge is acquired. The thrombectomy revolution, of which the middle cerebral artery (MCA) is the most common target, is an example of a clinical paradigm shift with a unique perspective on cerebrovascular anatomy. This article reviews important features of MCA anatomy in the context of thrombectomy. Recognizing that variation, frequently explained by evolutionary concepts, is the rule when it comes to branching pattern, vessel morphology, territory, or collateral potential is key to successful thrombectomy strategy.