Identifying the Sylvian Triangle on CT angiography: A technique for detecting distal middle cerebral artery occlusions.

Medium vessel occlusions (MeVOs), defined as occlusion of the M2/M3 and A2/A3 segments of the middle cerebral artery (MCA) and anterior cerebral artery, can be challenging to visualize on CT angiography (CTA) and MR angiography (MRA), given the anatomic complexity of the mid- and distal intracranial vasculature and smaller vessel caliber (Leary MC, Kidwell CS, Villablanca JP, et al. Validation of computed tomographic MCA "dot" sign: an angiographic correlation study. Stroke 2003; 34: 2636-2640; Luijten SPR, Wolff L, Duvekot MHC, et al. Diagnostic performance of an algorithm for automated large vessel occlusion (LVO) detection on CTA. J Neurointerv Surg 2022; 14: 794-798). In turn, the appearance of a sudden vessel cutoff in these vascular distributions on CTA or MRA is not always straightforward and may represent true occlusion, variant anatomy, and/or artifact (Leary MC, Kidwell CS, Villablanca JP, et al. Validation of computed tomographic MCA "dot" sign: an angiographic correlation study. Stroke 2003; 34: 2636-2640; Luijten SPR, Wolff L, Duvekot MHC, et al. Diagnostic performance of an algorithm for automated LVO detection on CTA. J Neurointerv Surg 2022; 14: 794-798). Given the importance of rapidly establishing an accurate diagnosis in the setting of stroke, combined with recent clinical trials and movements promoting the efficacy of endovascular therapeutic approaches to treat MeVOs, it remains imperative to detect such occlusions accurately and quickly on imaging. In turn, we present five imaging patterns of the Sylvian Triangle on sagittal reformatted images from CTA Head examinations, which our practice has utilized to assess patency of the M2 and M3 divisions. This approach is rapidly deployable and can be utilized by radiology and non-radiology healthcare providers alike, thus facilitating rapid and accurate diagnosis of MeVO, timely evaluation of candidacy for endovascular therapy, and ultimately supporting favorable door-to-intervention time and successful patient outcomes.

Outcomes of mechanical thrombectomy in anticoagulated patients with acute distal and medium vessel stroke.

BACKGROUND: Stroke remains a major health concern globally, with oral anticoagulants widely prescribed for stroke prevention. The efficacy and safety of mechanical thrombectomy (MT) in anticoagulated patients with distal medium vessel occlusions (DMVO) are not well understood. METHODS: This retrospective analysis involved 1282 acute ischemic stroke (AIS) patients who underwent MT in 37 centers across North America, Asia, and Europe from September 2017 to July 2023. Data on demographics, clinical presentation, treatment specifics, and outcomes were collected. The primary outcomes were functional outcomes at 90 days post-MT, measured by modified Rankin Scale (mRS) scores. Secondary outcomes included reperfusion rates, mortality, and hemorrhagic complications. RESULTS: Of the patients, 223 (34%) were on anticoagulation therapy. Anticoagulated patients were older (median age 78 vs 74 years; p < 0.001) and had a higher prevalence of atrial fibrillation (77% vs 26%; p < 0.001). Their baseline National Institutes of Health Stroke Scale (NIHSS) scores were also higher (median 12 vs 9; p = 0.002). Before propensity score matching (PSM), anticoagulated patients had similar rates of favorable 90-day outcomes (mRS 0-1: 30% vs 37%, p = 0.1; mRS 0-2: 47% vs 50%, p = 0.41) but higher mortality (26% vs 17%, p = 0.008). After PSM, there were no significant differences in outcomes between the two groups. CONCLUSION: Anticoagulated patients undergoing MT for AIS due to DMVO did not show significant differences in 90-day mRS outcomes, reperfusion, or hemorrhage compared to non-anticoagulated patients after adjustment for covariates.

Management of refractory bacterial meningitis-associated cerebral vasospasm: illustrative case.

BACKGROUND: Cerebral vasospasm is an alarming complication of acute bacterial meningitis with potentially devastating consequences. It is essential for providers to recognize and treat it appropriately. Unfortunately, there is no well-established approach to the management of postinfectious vasospasm, which makes it especially challenging to treat these patients. More research is needed to address this gap in care. OBSERVATIONS: Here, the authors describe a patient with postmeningitis vasospasm that was refractory to induced hypertension, steroids, and verapamil. He eventually responded to a combination of intravenous (IV) and intra-arterial (IA) milrinone followed by angioplasty. LESSONS: To our knowledge, this is the first report of successfully using milrinone as vasodilator therapy in a patient with postbacterial meningitis-associated vasospasm. This case supports the use of this intervention. In future cases of vasospasm after bacterial meningitis, IV and IA milrinone should be trialed earlier with consideration of angioplasty.

Comparing treatment outcomes of various intracranial bifurcation aneurysms locations using the Woven EndoBridge (WEB) device.

BACKGROUND: The Woven EndoBridge (WEB) device has Food and Drug Administration approval for treatment of wide-necked intracranial bifurcation aneurysms. The WEB device has been shown to result in adequate occlusion in bifurcation aneurysms overall, but its usefulness in the individual bifurcation locations has been evaluated separately only in few case series, which were limited by small sample sizes. OBJECTIVE: To compare angiographic and clinical outcomes after treatment of bifurcation aneurysms at various locations, including anterior communicating artery (AComA), anterior cerebral artery (ACA) bifurcation distal to AComA, basilar tip, internal carotid artery (ICA) bifurcation, and middle cerebral artery (MCA) bifurcation aneurysms using the WEB device. METHODS: A retrospective cohort analysis was conducted at 22 academic institutions worldwide to compare treatment outcomes of patients with intracranial bifurcation aneurysms using the WEB device. Data include patient and aneurysm characteristics, procedural details, angiographic and functional outcomes, and complications. RESULTS: A total of 572 aneurysms were included. MCA (36%), AComA (35.7%), and basilar tip (18.9%) aneurysms were most common. The rate of adequate aneurysm occlusion was significantly higher for basilar tip (91.6%) and ICA bifurcation (96.7%) aneurysms and lower for ACA bifurcation (71.4%) and AComA (80.6%) aneurysms (p=0.04). CONCLUSION: To our knowledge, this is the most extensive study to date that compares the treatment of different intracranial bifurcation aneurysms using the WEB device. Basilar tip and ICA bifurcation aneurysms showed significantly higher rates of aneurysm occlusion than other locations.

Multicenter Study for the Treatment of Sidewall versus Bifurcation Intracranial Aneurysms with Use of Woven EndoBridge (WEB).

Background The Woven EndoBridge (WEB) device was explicitly designed for wide-neck intracranial bifurcation aneurysms. Small-scale reports have evaluated the off-label use of WEB devices for the treatment of sidewall aneurysms, with promising outcomes. Purpose To compare the angiographic and clinical outcomes of the WEB device for the treatment of sidewall aneurysms compared with the treatment of bifurcation aneurysms. Materials and Methods A retrospective review of the WorldWideWEB Consortium, a synthesis of retrospective databases spanning from January 2011 to June 2021 at 22 academic institutions in North America, South America, and Europe, was performed to identify patients with intracranial aneurysms treated with the WEB device. Characteristics and outcomes were compared between bifurcation and sidewall aneurysms. Propensity score matching (PSM) was used to match by age, pretreatment ordinal modified Rankin Scale score, ruptured aneurysms, location of aneurysm, multiple aneurysms, prior treatment, neck, height, dome width, daughter sac, and incorporated branch. Results A total of 683 intracranial aneurysms were treated using the WEB device in 671 patients (median age, 61 years [IQR, 53-68 years]; male-to-female ratio, 1:2.5). Of those, 572 were bifurcation aneurysms and 111 were sidewall aneurysms. PSM was performed, resulting in 91 bifurcation and sidewall aneurysms pairs. No significant difference was observed in occlusion status at last follow-up, deployment success, or complication rates between the two groups. Conclusion No significantly different outcomes were observed following the off-label use of the Woven EndoBridge, or WEB, device for treatment of sidewall aneurysms compared with bifurcation aneurysms. The correct characterization of the sidewall aneurysm location, neck angle, and size is crucial for successful treatment and lower retreatment rate. © RSNA, 2022 See also the editorial by Hetts in this issue.

Transradial versus transfemoral access for embolization of intracranial aneurysms with the Woven EndoBridge device: a propensity score-matched study.

OBJECTIVE: Transradial access (TRA) is commonly utilized in neurointerventional procedures. This study compared the technical and clinical outcomes of the use of TRA versus those of transfemoral access (TFA) for intracranial aneurysm embolization with the Woven EndoBridge (WEB) device. METHODS: This is a secondary analysis of the Worldwide WEB Consortium, which comprises multicenter data related to adult patients with intracranial aneurysms who were managed with the WEB device. These aneurysms were categorized into two groups: those who were treated with TRA or TFA. Patient and aneurysm characteristics and technical and clinical outcomes were compared between groups. Propensity score matching (PSM) was used to match groups according to the following baseline characteristics: age, sex, subarachnoid hemorrhage, aneurysm location, bifurcation aneurysm, aneurysm with incorporated branch, neck width, aspect ratio, dome width, and elapsed time since the last follow-up imaging evaluation. RESULTS: This study included 682 intracranial aneurysms (median [interquartile range] age 61.3 [53.0-68.0] years), of which 561 were treated with TFA and 121 with TRA. PSM resulted in 65 matched pairs. After PSM, both groups had similar characteristics, angiographic and functional outcomes, and rates of retreatment, thromboembolic and hemorrhagic complications, and death. TFA was associated with longer procedure length (median 96.5 minutes vs 72.0 minutes, p = 0.006) and fluoroscopy time (28.2 minutes vs 24.8 minutes, p = 0.037) as compared with TRA. On the other hand, deployment issues were more common in those treated with TRA, but none resulted in permanent complications. CONCLUSIONS: TRA has comparable outcomes, with shorter procedure and fluoroscopy time, to TFA for aneurysm embolization with the WEB device.

Simulation of superselective catheterization for cerebrovascular lesions using a virtual injection software.

BACKGROUND: This report addresses the feasibility of virtual injection software based on contrast-enhanced cone-beam CTs (CBCTs) in the context of cerebrovascular lesion embolization. Intracranial arteriovenous malformation (AVM), dural arteriovenous fistula (AVF) and mycotic aneurysm embolization cases with CBCTs performed between 2013 and 2020 were retrospectively reviewed. Cerebrovascular lesions were reviewed by 2 neurointerventionalists using a dedicated virtual injection software (EmboASSIST, GE Healthcare; Chicago, IL). Points of Interest (POIs) surrounding the vascular lesions were first identified. The software then automatically displayed POI-associated vascular traces from vessel roots to selected POIs. Vascular segments and reason for POI identification were recorded. Using 2D multiplanar reconstructions from CBCTs, the accuracy of vascular traces was assessed. Clinical utility metrics were recorded on a 3-point Likert scale from 1 (no benefit) to 3 (very beneficial). RESULTS: Nine cases (7 AVM, 1 AVF, 1 mycotic aneurysm) were reviewed, with 26 POIs selected. Three POIs were in 2nd order segments, 8 POIs in 3rd order segments and 15 POIs in 4th order segments of their respective arteries. The reviewers rated all 26 POI traces - involving a total of 90 vascular segments - as accurate. The average utility score across the 8 questions were 2.7 and 2.8 respectively from each reviewer, acknowledging the software's potential benefit in cerebrovascular embolization procedural planning. CONCLUSION: The operators considered CBCT-based virtual injection software clinically useful and accurate in guiding and planning cerebrovascular lesion embolization in this retrospective review. Future prospective studies in larger cohorts are warranted for validation of this modality.

Balloon occlusion as an adjunctive technique during sclerotherapy of Puig's classified advanced venous malformations.

OBJECTIVE: Puig types 2 through 4 venous malformations (VMs) are challenging to treat with sclerotherapy given their robust systemic outflow. Endovenous balloon occlusion offers a means of temporarily occluding systemic venous outflow to allow for more complete sclerotherapy. This study reviews our experience of implementing this technique in patients with Puig advanced (types 2 through 4) VMs. METHODS: An IRB approved review of treated venous malformations from 2013-2016 revealed 10 patients fitting inclusion criteria. Patient demographics, pre-procedural imaging, intra-procedural technical parameters, and post-procedural follow-up outcomes were recorded. All patients underwent temporary balloon occlusion of a systemic or major draining vein during sclerotherapy. Embolic agents included n-butyl cyanoacrylate glue, sodium tetradecyl sulfate foam, and coils. Standard 5 French angioplasty balloons ranged from 4 to 8 mm diameter and 2 to 8 cm length depending on vessel requiring occlusion. All patients underwent minimum 3-year follow-up questionnaire administration re-assessing resolution of lesion symptomology and post-procedural quality of life (QoL) measures. RESULTS: Of the 10 VMs treated, 2 were Type 2, 6 were Type 3, and 2 were Type 4. More than one sclerotherapy session was required in 7/10 patients (mean: 2, range: 1-4). Most common sites of VM systemic drainage included subclavian, popliteal, internal/external jugular, and basilic veins. All patients had no indication for further sclerotherapy following adjunctive balloon occlusion. No non-target embolization or immediate post-procedural complications occurred. Follow-up questionnaires (mean interval: 3 years 6 months, range: 3 years-3 years 11 months) confirmed the persistence of embolization effects, improved QoL, and no additional sclerotherapy sessions for all patients in the cohort. CONCLUSIONS: Endovenous balloon occlusion as an adjunct to sclerotherapy can be considered when treating patients with types 2-4 venous malformations. This technique lowers the risk of non-target systemic venous embolization, allowing for operator-driven deeper intralesional sclerosant penetration and subsequently maintained treatment efficacy.

Venous sinus stenting for the treatment of isolated pulsatile tinnitus: Results of a prospective trial.

OBJECTIVES: This prospective study evaluates the effectiveness and safety of venous sinus stenting for patients with isolated pulsatile tinnitus and lateral sinus stenosis. METHODS: Patients with isolated pulsatile tinnitus and lateral sinus stenosis with a minimum trans stenotic gradient of 4 mm Hg were treated with stenting. Pulsatile tinnitus before and after treatment was assessed with the Tinnitus Handicap Inventory (THI). Periprocedural adverse events, neurological complications, clinical and radiographic follow-up were also recorded. RESULTS: A total of 42 patients (41 females and 1 male) were included in the study (median age of 37.5 years). Thirty patients had post-stenotic fusiform and 12 had post-stenotic saccular venous sinus aneurysm. In addition to stenting, coils were used to treat the patients with saccular venous aneurysms. The median follow-up was 5 months (range 1 to 34 months). Most patients had complete (39/42) or near-complete (2/42) resolution of their pulsatile tinnitus post-procedure. There were no serious adverse events. CONCLUSION: Stenting of the lateral venous sinus is a safe and effective treatment for patients with isolated pulsatile tinnitus due to venous sinus stenosis.

Magnetic resonance venography for 3-dimensional live guidance during venous sinus stenting.

PURPOSE: The purpose of this study was to report the technique for intraprocedural guidance of endovascular Venous Sinus Stenting procedures using 3-Dimensional (3D) Magnetic Resonance Venography (MRV) as an overlay on live biplanar fluoroscopy. MATERIALS AND METHODS: Venous sinus stenting procedures performed between April and December, 2017 with 3D MRV fusion for live guidance were reviewed in this study. A thin-slice, contrast-enhanced MR Venogram was used to create 2 3D models - vessels and skull - for procedural guidance via augmented fluoroscopy (Vessel ASSIST, GE Healthcare, Chicago, IL). The skull model was used in the registration of the 3D overlay on both the frontal and lateral planes, which required 1-2 min of procedural time. The vessel model was used to mark landmarks such as the cortical vein ostia and stenosis on the 3D overlay fused with biplanar fluoroscopy. The retrospective imaging review was conducted by 3 neurointerventionalists and relied on a consensus confidence ranking on a 3-point Likert scale from 1- low confidence to 3- high confidence. The neurointerventionalists first reviewed the conventional 2-dimensional pre-stent deployment fluoroscopy images and then reviewed the corresponding images with the 3D MRV overlay. They ranked their confidence in their understanding of cortical venous anatomy for each group. Statistical analysis was performed using a Paired T Test at a 99% confidence interval. RESULTS: Ten cases were included in the retrospective image review. Operator confidence regarding the location of cortical veins was significantly increased using 3D MRV fusion during venous sinus stenting procedures (1.9 vs 2.9, p = .001). CONCLUSION: 3-Dimensional MRV fusion is feasible and helpful in understanding the venous sinus anatomy and location of important cortical veins during venous sinus stenting procedures.

Intraprocedural guidance for recanalization of post-thrombotic venous lesions using live overlay of center lines from pre-operative cross-sectional imaging: a preliminary experience.

PURPOSE: Pre-procedural contrast-enhanced CT and MRI imaging is typically acquired prior to deep venous recanalization procedures for post-thrombotic syndrome. This technical note reports the utility of live-overlay of augmented centerlines extracted from pre-procedural CT and MRI imaging in facilitating fluoroscopic-guided recanalization of post-thrombotic venous lesions. METHODS AND MATERIALS: Six patients with pre-procedural CT or MR venography data were incorporated into a commercially available 3D overlay software (Vessel Assist, GE Healthcare, Buc, France) during venous disease interventions for post-thrombotic venous lesions. Procedures were performed on the GE Discovery IGS 740 fluoroscopy system. After manual determination of the vasculature from preprocedural CT or MR, centerlines were created representing the location and trajectory of the vessels. Steps showcasing the creation of centerlines and their representation during overlay with real-time fluoroscopic guidance in these cases are outlined. Time required to cross the post-thrombotic and occlusive venous segments were reviewed. RESULTS: All iliocaval recanalization procedures were successfully performed utilizing vessel centerline 3D overlay. In one case where occlusion extended to the femoral vein, mis-registration was identified over the femoral anatomy due to a complex leg rotation compared to pre-procedural imaging. No procedural complications related to utilization of software were noted. Average crossing time for occlusions was 3.4 min (range 1.6-5.2). CONCLUSION: 3D overlay with vessel tracking from pre-procedural CT and MRI imaging is technically feasible and assists in catheter navigation for post-thrombotic venous segments. While results from these preliminary experiences support the continued use of this technology, further prospective and comparative evaluation of this technique is warranted to assess for added value in technical success, reductions in procedure time or reductions in radiation exposure.

Sequential Interventional Management of Osseous Neoplasms via Embolization, Cryoablation, and Osteoplasty.

The purpose of this study is to determine if sequential interventional therapy can become a mainstay option in providing palliation from fastidious osseous neoplasms in patients with pain refractory to oral analgesia and radiotherapy. This retrospective monocentric study was approved by our institutional review board. Between July 2012 and August 2014, we reviewed 15 patients (6 women, 9 men; age range of 36-81 years) who underwent embolization followed by cryoablation, with or without osteoplasty. Patient demographics and tumor characteristics, including primary histology and the location of metastasis, were included in our review. Pain intensity at baseline, after radiotherapy, and after sequential interventional therapy was reviewed using the hospital electronic medical record. The use of oral analgesia and procedural complications was also noted. Data was then assessed for normality and a two-tailed Student's t-test was performed on mean pain scores for difference phases of treatment. While radiotherapy offers pain relief with a mean pain score of 7.25 ±1.5 (p =<.0001), sequential interventional therapy results in better comfort as demonstrated by a mean pain score of 3.9 ± 2.6 (p=.0015). Moreover, all patients who reported oral analgesic use at presentation reported a decrease in their requirement after sequential interventional therapy. Embolization and cryoablation were performed in all patients, while osteoplasty was indicated in 6 cases. There was no difference in postprocedural pain intensity between patients who required osteoplasty and patients who did not (p = 0.7514). There were no complications observed during treatment. This retrospective study shows that sequential intervention with transarterial embolization, cryoablation, and osteoplasty is both safe and efficacious for bone pain refractory to the current standard of care. We demonstrated that this combination therapy has the potential to become an effective mainstay treatment paradigm in the palliative care of osseous neoplasm to improve quality of life.

Extrahepatic Clinical Application of Vessel Tracking Software and 3D Roadmapping Tools: Preliminary Experience.

This article demonstrates the use of a representative commercially available automated vessel-tracking software originally intended for liver-only application (Vessel Assist Flight Plan for Liver; GE) in 4 patients. Treatment settings included embolization of small bowel hemorrhage source, treatment of renal cell carcinoma, management of symptomatic benign prostate hypertrophy, and detection with subsequent closure of a mesenteric pseudoaneurysm. All patients were treated successfully.

Assessment of Optimal Imaging Protocol Sequences After Laser-Induced Thermal Therapy for Intracranial Tumors.

BACKGROUND: Magnetic resonance-guided laser-induced thermal therapy (MRgLITT) is a novel, minimally invasive method currently being used to treat a wide range of intracranial pathologies. No accepted guidelines exist on what the appropriate magnetic resonance imaging (MRI) sequences are for evaluating short-term postablation changes, especially when patients are not able to receive gadolinium. OBJECTIVE: To evaluate which MRI sequences provide the greatest inter-rater reliability and least amount of variability in assessment of ablation volume after MRgLITT for intracranial neoplasms. METHODS: Twenty patients who received MRgLITT were included. Three raters calculated volumetric measurements on postprocedural axial spoiled gradient recalled (SPGR), fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and gradient echo (GRE) sequences. Measured volumes were analyzed using intraclass correlation to determine which protocol had the most concordance among the 3 raters. RESULTS: Postcontrast SPGR sequences were most concordant in our study, with an intraclass correlation of 0.981. DWI was the next-most concordant imaging sequence with an intraclass correlation of 0.958. The least concordant were GRE (0.895) and FLAIR (0.866) images. SPGR was also the least variable and had the most consistent volume ratings compared to the other sequences. CONCLUSION: This study is the first to evaluate the inter-rater reliability of different MRI sequence protocols in the context of post-MRgLITT volumetric evaluation. SPGR postcontrast images facilitate the greatest interobserver concordance when characterizing post-MRgLITT tumor appearance and volumetrics, with DWI ranked second. Based on our findings, SPGR sequences are likely to yield the highest degree of concordance in post-MRgLITT lesion evaluation. When gadolinium cannot be given, DWI should provide the next most reliable estimation.

Ultrasound-guided thrombin injection for treatment of superficial traumatic pseudoaneurysms and associated expanding hematomas: experience in five patients.

BACKGROUND: Angiography allows for excellent characterization and treatment of traumatic pseudoaneurysms. However, ultrasound-guided thrombin injection for pseudoaneurysm thrombosis allows for radiation-free treatment of superficial pseudoaneurysms and superficial expanding hematomas. METHODS: A retrospective review of 5 patient cases treated under this paradigm was performed following institutional review board approval. Outcomes following intervention were recorded and compared amongst the patient cohort. RESULTS: Ultrasound-guided closure of traumatic pseudoaneurysms allowed for reduced procedural times and procedural invasiveness. CONCLUSIONS: As demonstrated by the following cases, ultrasound guided thrombin injection is a good method of primary treatment for superficial pseudoaneurysms, or as an alternative treatment in cases where transcatheter embolization fails.