Ravindran, Krishnan

Introduction Poor‐grade aneurysmal subarachnoid hemorrhage (aSAH) is associated with high mortality. Overall, 20–30% of aSAH are described as poor grade. Despite recent advances in management strategies, prognosis of poor‐grade aSAH remains dismal. As such, we review the most current literature regarding management strategies that can be used to decrease the risk of the four most common causes of secondary brain injury: 1) aneurysm re‐rupture, 2) hydrocephalus, 3) cerebral salt wasting, and 4) delayed cerebral ischemia/vasospasm. Methods We present a 46‐year‐old female patient with poor‐grade aSAH after a loss of consciousness following thunderclap headache. Examination showed a dilated left pupil and Glasgow Coma Scale (GCS) of 4. Imaging revealed a ruptured anterior communicating artery aneurysm, and she was subsequently taken to the neuro‐interventional radiology suite for EVD placement. On POD 7 Transcranial Doppler (TCD) suggested moderate vasospam of left MCA. Two successful balloon angioplasties of the basilar, ACA‐A1, and MCA‐M1 were successfully performed on separate consecutive days. By POD 10, intermittent severe ICP spikes required targeted temperature management (TTM) with hypothermia. On POD 24, her ICP normalized, she was no longer comatose, and her EVD was clamped and removed. She was rapidly weaned off ventilator and transitioned to rehabilitation. 3‐months postoperatively, Modified Rankin Scale score was 0. Results Based upon the result of our literature review, we propose maintaining blood pressure below 160 mmHg prior to intervention, after which it can be increased to 160–240 mmHg to prevent vasospasm. Transcranial Doppler is essential to detect vasospasm as the aSAH symptoms subtle; once identified, vasospasm can be successfully treated with balloon angioplasty. Finally, targeted temperature management, mannitol, hypertonic saline, and neuromuscular paralysis are essential for postoperative management of ICP levels. Conclusions The multimodal approach should be considered when managing poor grade aSAH. Further research in aSAH management would benefit the patients who present with poor prognosis, thereby improving patient care and leading to a standard, effective approach for aSAH management.

BACKGROUND: The new sonolucent cranioplasty implant (clear polymethyl methacrylate, PMMA) adds functionality besides surgical reconstruction. One possible application uses the transcranioplasty ultrasound (TCUS) technique after PMMA cranioplasty to assess graft patency of extracranial-intracranial (EC-IC) bypass procedures. OBJECTIVE: To report our early multicenter experience. METHODS: This is a multicenter analysis of consecutive EC-IC bypass patients from 5 US centers (2019-2022) with closure postbypass using PMMA implant. RESULTS: Forty-four patients (median age 53 years, 68.2% females) were included. The most common indication for bypass was Moyamoya disease/syndrome (77.3%), and superficial temporal artery to middle cerebral artery bypass was the most common procedure (79.5%). Pretreatment modified Rankin Scales of 0 and 1 to 2 were noted in 11.4% and 59.1% of patients, respectively. Intraoperative imaging for bypass patency involved a combination of modalities; Doppler was the most used modality (90.9%) followed by indocyanine green and catheter angiography (86.4% and 61.4%, respectively). Qualitative TCUS assessment of graft patency was feasible in all cases. Postoperative inpatient TCUS confirmation of bypass patency was recorded in 56.8% of the cases, and outpatient TCUS surveillance was recorded in 47.7%. There were no cases of bypass failure necessitating retreatment. Similarly, no implant-related complications were encountered in the cohort. Major complications requiring additional surgery occurred in 2 patients (4.6%) including epidural hematoma requiring evacuation (2.3%) and postoperative surgical site infection (2.3%) that was believed to be unrelated to the implant. CONCLUSION: This multicenter study supports safety and feasibility of using sonolucent PMMA implant in EC-IC bypass surgery with the goal of monitoring bypass patency using TCUS.

BACKGROUND: Dural arteriovenous fistulas (dAVFs) located at craniocervical junction are extremely rare (1%-2% of intracranial/spinal dAVFs). Their angio-architectural complexity renders endovascular embolization to be challenging given multiple small feeders with risk of embolysate reflux into vertebral artery and limited transvenous access. The available literature discussing microsurgery for these lesions is limited to few case reports. OBJECTIVE: To report a multicenter experience assessing microsurgery safety/efficacy. METHODS: Prospectively maintained registries at 13 North American centers were queried to identify craniocervical junction dAVFs treated with microsurgery (2006-2021). RESULTS: Thirty-eight patients (median age 59.5 years, 44.7% female patients) were included. The most common presentation was subarachnoid/intracranial hemorrhage (47.4%) and myelopathy (36.8%) (92.1% of lesions Cognard type III-V). Direct meningeal branches from V3/4 vertebral artery segments supplied 84.2% of lesions. All lesions failed (n = 5, 13.2%) or were deemed inaccessible/unsafe to endovascular treatment. Far lateral craniotomy was the most used approach (94.7%). Intraoperative angiogram was performed in 39.5% of the cases, with angiographic cure in 94.7% of cases (median imaging follow-up of 9.2 months) and retreatment rate of 5.3%. Favorable last follow-up modified Rankin Scale of 0 to 2 was recorded in 81.6% of the patients with procedural complications of 2.6%. CONCLUSION: Craniocervical dAVFs represent rare entity of lesions presenting most commonly with hemorrhage or myelopathy because of venous congestion. Microsurgery using a far lateral approach provides robust exposure and visualization for these lesions and allows obliteration of the arterialized draining vein intradurally as close as possible to the fistula point. This approach was associated with a high rate of angiographic cure and favorable clinical outcomes.

Background Basal ganglia infarcts are thought to carry worse clinical outcomes compared with other infarct patterns. We aimed to investigate whether pretreatment topographic infarct patterns including complete basal ganglia involvement versus other infarct patterns help predict mechanical thrombectomy outcomes. Methods This was a review of a prospectively collected database of consecutive mechanical thrombectomy patients with anterior circulation large vessel occlusion strokes between January 2014 and November 2018. Patients were categorized into the following 2 groups: (1) total basal ganglia (TBG) strokes defined as infarcts affecting both the caudate and lentiform nuclei regardless of cortical involvement and (2) other infarct patterns. Infarct location was assessed on preprocedure noncontrast computed tomography using an automated software (e‐ASPECTS). Baseline characteristics and outcome measures were compared. Results A total of 1011 patients were analyzed of which 234 (23.12%) had TBG strokes. Patients with TBG strokes were younger ( P =0.01); had higher National Institutes of Health Stroke Scale (NIHSS) ( P =0.006), lower e‐ASPECTS ( P <0.001), and lower systolic blood pressure ( P =0.024); and had diabetes less often ( P =0.01). Baseline characteristics were otherwise comparable between groups. Involvement of the caudate or lentiform nucleus alone was observed in 237 (30.5%) and 21 (2.7%) patients, respectively, in the other infarct patterns group. No internal capsule involvement was detected in either group. There were no differences in terms of 90‐day functional outcomes whether dichotomized (modified Rankin Scale score≤2: TBG=44.6% versus other=50.1%; P =0.14) or looking at the entire spectrum of the scale (shift analysis; P =0.74). However, TBG strokes had significantly higher rates of any parenchymal hematomas (15.4% versus 8.2%; P =0.001), an association that held true in multivariable analysis (adjusted odds ratio, 2.57 [95% CI, 1.41–4.62]; P =0.002). Conclusions Despite increased rates of hemorrhagic transformation, ganglionic infarcts carry similar functional outcomes after mechanical thrombectomy compared with other stroke patterns.

In this surgical video, the authors present a successful minimally invasive (MIS) lateral retroperitoneal transpsoas approach for resection of an L4 nerve root schwannoma. They describe the surgical approach in detail, with special emphasis on patient positioning for an orthogonal view, as well as technical nuances throughout the procedure. Using a sequential tubular retractor, they performed a microscopic dissection of the lesion. The tumor was debulked and the tumor capsule was disconnected from the surrounding tissue. During dissection, direct stimulation identified a functional nerve root that was carefully dissected from the tumor capsule. The tumor was then removed en bloc. The video can be found here: https://stream.cadmore.media/r10.3171/2022.3.FOCVID2220

Endovascular treatment of recurrent basilar aneurysms is challenging due to significant changes in the configuration of the aneurysm and adjacent vessels from prior interventions.1 Coil compaction is a common cause of recurrence and alters the aneurysm morphology significantly.2–4 Stenting of the basilar artery into a posterior cerebral artery modifies the angles between these vessels.5 In this video, we discuss a combined approach via the anterior and posterior circulation for stent-assisted coiling of a recurrent basilar tip aneurysm (Video 1) . A patient in their 40s with a history of ruptured aneurysm underwent multiple endovascular interventions including coiling, stent-assisted coiling, and Woven Endobridge (WEB) device. The patient presented with worsening headaches and underwent treatment with stent-assisted coiling for recurrence. After encountering challenges with direct access from the basilar artery, a combined anterior and posterior circulation approach was used.6 The stent was deployed through the posterior communicating artery and a snare was used to navigate the complex anatomy. Video 1

Abstract In-stent stenosis has a reported prevalence of 14% to 19% at 1-yr follow-up after carotid stenting and is associated with an increased risk of acute ischemic stroke. 1,2 Risk factors include female sex, diabetes, and dyslipidemia. Cutting balloon angioplasty is a safe and effective treatment modality for the treatment of carotid in-stent stenosis, and alternative treatment options include observation with medical management and placement of another stent. 3,4 The authors present the case of a 61-yr-old man with carotid in-stent restenosis and progressive worsening on serial imaging with ultrasound. The patient had a history of carotid stenting for symptomatic stenosis 6 mo prior and was maintained on aspirin and clopidogrel. In light of the progressive worsening, the in-stent stenosis was confirmed on computed tomography (CT) angiogram. The options were discussed with the patient and he consented for treatment with cutting balloon angioplasty. Final angiogram showed improvement of the luminal diameter with a residual stenosis of 15%. The patient tolerated the procedure well and was discharged home on postoperative day 1. Follow-up ultrasound demonstrated moderate improvement in peak systolic velocities, and the plan is to continue observation with a clinical follow-up and repeat carotid Dopplers at 3 mo.