Faculty Bibliography

BACKGROUND:Current imaging algorithms for post-device evaluation are limited by either poor representation of the device or poor delineation of the treated vessel. Combining the high-resolution images from a traditional three-dimensional digital subtraction angiography (3D-DSA) protocol with the longer cone-beam computed tomography (CBCT) protocol may provide simultaneous visualization of both the device and the vessel content in a single volume, improving the accuracy and detail of the assessment. We aim here to review our use of this technique which we termed "SuperDyna". METHODS:In this retrospective study, patients who underwent an endovascular procedure between February 2022 and January 2023 were identified. We analyzed patients who had both non-contrast CBCT and 3D-DSA post-treatment and collected information on pre-/post-blood urea nitrogen, creatinine, radiation dose, and the intervention type. RESULTS:In 1 year, SuperDyna was performed in 52 (of 1935, 2.6%) patients, of which 72% were women, median age 60 years. The most common reason for the addition of the SuperDyna was for post-flow diversion assessment (n=39). Renal function tests showed no changes. The average total procedure radiation dose was 2.8 Gy, with 4% dose and ~20 mL of contrast attributed to the additional 3D-DSA needed to generate the SuperDyna. CONCLUSIONS:The SuperDyna is a fusion imaging method that combines high-resolution CBCT and contrasted 3D-DSA to evaluate intracranial vasculature post-treatment. It allows for more comprehensive evaluation of the device position and apposition, aiding in treatment planning and patient education.

Patients with stroke symptoms due to acute basilar artery occlusion can benefit from endovascular thrombectomy.1 2 Several papers have reported unwanted events during thrombectomy procedures such as breakage, fragmentation, or even intravascular migration of the devices or catheter pieces. These papers also presented methods or techniques to retrieve defective devices such as a snare, retrievable stents, or balloons.3-6Video 1 presents a case of basilar thrombectomy that was complicated with fragmentation and then distal migration of a Marksman microcatheter tip into the left posterior cerebral artery. The video shows the bailout technique that was used to retrieve the migrated catheter tip using a gentle/simple and posterior circulation-friendly technique-a technique based on fundamental neurointerventional concepts.neurintsurg;jnis-2022-019687v1/V1F1V1Video 1 This video demonstrates the use of a bailout technique to retrieve a migrated microcatehter tip after basilar artery thrombectomy.

BACKGROUND:We report the largest multicenter experience to date of utilizing the Comaneci device for endovascular treatment of refractory intracranial vasospasm. METHODS:Consecutive patients undergoing Comaneci mechanical dilatation for vasospasm were extracted from prospectively maintained registries in 11 North American centers (2020-2022). Intra-arterial vasodilators (IAV) were allowed, with the Comaneci device utilized after absence of vessel dilation post-infusion. Pre- and post-vasospasm treatment scores were recorded for each segment, with primary radiological outcome of score improvement post-treatment. Primary clinical outcome was safety/device-related complications, with secondary endpoints of functional outcomes at last follow-up. RESULTS:A total of 129 vessels in 40 patients (median age 52 years; 67.5% females) received mechanical dilation, 109 of which (84.5%) exhibited pre-treatment severe-to-critical vasospasm (ie, score 3/4). Aneurysmal subarachnoid hemorrhage was the most common etiology of vasospasm (85%), with 65% of procedures utilizing Comaneci-17 (92.5% of patients received IAV). The most treated segments were anterior cerebral artery (34.9%) and middle cerebral artery (31%). Significant vasospasm drop (pre-treatment score (3-4) to post-treatment (0-2)) was achieved in 89.9% of vessels (96.1% of vessels experienced ≥1-point drop in score post-treatment). There were no major procedural/post-procedural device-related complications. Primary failure (ie, vessel unresponsive) was encountered in one vessel (1 patient) (1/129; 0.8%) while secondary failure (ie, recurrence in previously treated segment requiring retreatment in another procedure) occurred in 16 vessels (7 patients) (16/129; 12.4%), with median time-to-retreatment of 2 days. Favorable clinical outcome (modified Rankin Scale 0-2) was noted in 51.5% of patients (median follow-up 6 months). CONCLUSIONS:The Comaneci device provides a complementary strategy for treatment of refractory vasospasm with reasonable efficacy/favorable safety. Future prospective trials are warranted.

Purpose of review: This review presents the critical appraisal of current therapeutic strategies for patients with large-vessel occlusion (LVO) acute ischemic stroke (AIS). We provide the reader with most recent evidence supporting endovascular thrombectomy (EVT), different techniques used for thrombectomy, and highlight knowledge gaps regarding therapeutic efficacy of this intervention in respective subgroup of these patients based on site of occlusion, size of ischemic core, time from symptom onset, utility of concurrent intravenous thrombolysis (IVT), mild strokes, or tandem occlusions. Recent findings: EVT is the established standard of care for patients with moderate-severe LVO-AIS presenting within 24 h of symptom onset and favorable perfusion imaging irrespective of IVT. The DIRECT-MT and SKIP randomized clinical trials (RCT) established that EVT without IVT for eligible patients is not non-inferior to concurrent IVT. The RESCUE-Japan LIMIT randomized controlled trial showed EVT in patients with ASPECTS score of 3"“5 presenting within 6 h of symptom onset or within 24 h if no early ischemic change was seen on MRI FLAIR sequence. Good functional outcome at 90 days (mRS 0"“3) was seen in 31% patients undergoing EVT and only in 12.7% in the medical group (relative risk 2.43, 95%CI 1.35"“4.37, p = 0.002). Any ICH was notably higher in the EVT group (58% versus 31.4%, p < 0.001). The SELECT-2 RCT enrolled patients with CT ASPECTS of 3"“5, or CT or MR perfusion core > 50 cc. The mRS scores moved toward functionally independent survival, with a generalized odds ratio favoring thrombectomy of 1.51 (95% CI 1.20"“1.89; p < 0.001). In addition, a phase 2b, randomized, placebo-controlled clinical trial, CHOICE, showed that intraarterial administration of alteplase (0.225 mg/kg; maximum dose 22.5 mg) after successful EVT (TICI 2b"“3) led to 18.6% increase (adjusted risk difference) in excellent functional outcomes at 90 days (59% versus 40.4%, 95% CI 0.3"“36.4%, p = 0.047). Summary: The industry has kept pace with the evolving needs and optimizing devices to achieve desired procedural efficacy for EVT resulting in great functional outcomes. We continue to explore the means to expand the indication and eligibility of patients suffering from LVO-AIS who would benefit from this life-saving procedure.

The aim of this review is to describe the acquisition and reformatting of state of the art high resolution cone beam CT (HR-CBCT) and demonstrate its role in multiple neurovascular conditions as a tool to improve the understanding of disease and guide therapeutic decisions. First, we will review the basic principle of CBCT acquisition, followed by the injection protocols and the reformatting paradigms. Next, multiple applications in different pathological conditions such as aneurysms, arteriovenous malformations, dural arteriovenous fistulas, and stroke will be described. HR-CBCT angiography, widely available, is uniquely useful in certain clinical scenarios to improve the understanding of disease and guide therapeutic decisions. It rapidly is becoming an essential tool for the contemporary neurointerventionalist.AChoAho.

Meaningful contributions to neurointerventional practice may be possible by considering the dynamic aspects of angiography in addition to fixed morphologic information. The functional approach to venous anatomy requires integration of the traditional static anatomic features of the system-deep, superficial, posterior fossa, medullary veins, venous sinuses, and outflow routes into an overall appreciation of how a classic model of drainage is altered, embryologically, or pathologically, depending on patterns of flow-visualization made possible by angiography. In this review, emphasis is placed on balance between alternative venous networks and their redundancy, and the problems which arise when these systems are lacking. The role of veins in major neurovascular diseases, such as dural arteriovenous fistulae, arteriovenous malformations, pulsatile tinnitus, and intracranial hypertension, is highlighted, and deficiencies in knowledge emphasized.

The persistent carotid-vertebrobasilar anastomoses are arterial communications between the anterior and posterior circulations due to the persistence of embryological connections. We here present an extremely rare instance of a transclival persistent carotid-vertebrobasilar anastomosis in a 10-month-old infant, which does not fit into any of the traditionally described categories, such as the trigeminal artery, hypoglossal artery, or proatlantal artery.

There are multiple treatment alternatives for cavernous dAVFs, with transvenous routes being most common. Among these routes, occluded inferior petrosal sinus is well-described, and, apart from being imaginative and elegant, it is also safe and effective. Herein we describe the application of this method to reach the fistulous pouch of a cavernous dAVF via an occluded superior petrosal sinus.