Hana Hallak

BACKGROUND: Hemorrhagic risk in dural arteriovenous fistulas (dAVFs) is largely determined by venous anatomy, but the contribution of systemic cardiovascular factors and their medical therapy remains poorly defined. This study examined associations between cardiovascular risk factors and antithrombotic use and hemorrhagic presentation, angiographic obliteration, and early functional outcomes after treatment. METHODS: We analyzed 1350 adults with intracranial dAVFs from the international Consortium for Dural Arteriovenous Fistula Outcomes Research registry, which retrospectively accrued cases across 14 centers in 4 countries between 1990 and 2017. Demographics, cardiovascular comorbidities, antithrombotic use, angioarchitectural features, treatment strategies, and follow-up outcomes were collected from prospectively maintained databases. Primary end points were hemorrhagic presentation, angiographic obliteration, and 90-day functional status after treatment. Univariable and multivariable logistic regressions were performed with model-specific adjustments. RESULTS: Hemorrhage occurred in 375 patients (27.8%) and was most strongly associated with high-grade dAVF classification and male sex; antithrombotic therapy was associated with lower odds of hemorrhagic presentation. Other cardiovascular risk factors showed no independent relationship with bleeding. Angiographic obliteration was achieved in 621 of 845 patients (73.5%). Hemorrhagic onset, high dAVF grade, and surgical treatment were independently associated with angiographic obliteration, whereas smoking and embolization demonstrated only nonsignificant trends after adjustment. At 90 days, 934 patients (88.9%) were functionally independent. Baseline modified Rankin Scale score was the strongest factor associated with 90-day functional outcome, while neither cardiovascular comorbidities nor treatment modality independently influenced functional status. CONCLUSIONS: In this large multicenter dAVF cohort, hemorrhagic presentation was most strongly associated with venous angioarchitecture. Male sex and antithrombotic therapy were also independently associated with hemorrhagic presentation. Angiographic obliteration was common, particularly among surgically treated lesions, and 90-day functional outcome was most strongly associated with baseline functional status.

BACKGROUND AND OBJECTIVES: Schwannomas are benign, slow-growing peripheral nerve sheath tumors. Approximately 8% of intracranial schwannomas originate from the trigeminal nerve. No consensus exists regarding superiority of outcomes after resection vs stereotactic radiosurgery (SRS) in the treatment of trigeminal schwannomas (TS). The aim of this study was to compare the efficacy and outcomes of resection vs SRS for TS management. METHODS: Embase, PubMed, and SCOPUS databases were queried from the date of inception to July 2023 for primary data reporting TS treatment outcomes after SRS or resection. Risk of bias was reported under Newcastle-Ottawa Scale. RESULTS: Overall, 29 retrospective observational studies comprising 949 patients were included in the analysis. A total of 13 studies (n = 589) reported outcomes after SRS, and 16 studies (n = 360) reported outcomes after surgical resection, and 182 patients in the SRS group had previous resection. To ensure statistical validity of comparing the cohorts, 3 checkpoints were assessed: the median age (SRS: 48 vs surgery: 40 years old, P < .01), tumor volume (5.2 vs 8.9 cm³, P = .06), and median follow-up (53.9 vs 48.5 months, P = .59), which reflected the choice of treatment. Compared with surgical resection, the SRS group demonstrated significantly higher rates of facial hypesthesia improvement (44% vs 12%, P < .01) and lower rates of new onset (4% vs 15%, P = .051) at last follow-up. Facial pain was less likely to improve (58% vs 81%, P = .024) after SRS compared with surgery. However, worsened (5% vs 1%, P = .71) and new facial pain (2% vs 1%, P = .55) were comparable between cohorts. CONCLUSION: SRS seems to offer improvement in rates of hypesthesia and trigeminal motor deficits compared with surgical resection for TS. However, facial pain improvement was more favorable after surgery. These findings highlight the importance of individualized treatment decisions based on patient characteristics, tumor profile, and pretreatment symptoms.

Diagnostic accuracy of arteriovenous malformations (AVMs) is imperative for delineating management. The current standard is digital subtraction angiography (DSA). Arterial spin labeling (ASL) is an understudied noninvasive, non-contrast technique that allows angioarchitecture visualization and additionally quantifies cortical and AVM cerebral blood flow and hemodynamics. This meta-analysis aims to compare ASL and DSA imaging in detecting and characterizing cerebral AVMs. EMBASE, Medline, Scopus, and Cochrane databases were queried from inception to July 2022 for reports of AVMs evaluated by DSA and ASL imaging. Fourteen studies with 278 patients evaluated using DSA and ASL imaging prior to intervention were included; pCASL in 11 studies (n = 239, 85.37%) and PASL in three studies (n = 41, 14.64%). The overall AVM detection rate on ASL was 99% (CI 97–100%); subgroup analysis revealed no difference between pCASL vs. PASL (99%; CI 96–100% vs. 100%; CI 95–100% respectively, p = 0.42). The correlation value comparing ASL and DSA nidus size was 0.99. DSA and ASL intermodality agreement Cohen’s k factor for Spetzler Martin Grading (SMG) was reported at a median of 0.98 (IQR 0.73–0.1), with a 1.0 agreement on SMG classification. A median of 25 arteries were detected by DSA (IQR 14.5–27), vs. 25 by ASL (IQR 14.5–27.5) at a median 0.92 k factor. ASL provides angioarchitectural visualization noninferior to DSA and additionally quantifies CBF. Our study suggests that ASL should be considered in the detection of AVMs, especially in patients with contrast contraindications or apprehension towards an invasive assessment.

In recent years, the endoscopic endonasal approach (EEA) for craniopharyngiomas has proven to be a safe option for extensive tumor resection, with minimal or no manipulation of the optic nerves and excellent visualization of the superior hypophyseal branches when compared to the Transcranial Approach (TCA). However, there is an ongoing debate regarding the criteria for selecting different approaches. To explore the current results of EEA and discuss its role in the management of craniopharyngiomas, we performed MEDLINE, Embase, and LILACS searches from 2012 to 2022. Baseline characteristics, the extent of resection, and clinical outcomes were evaluated. Statistical analysis was performed through an X² and Fisher exact test, and a comparison between quantitative variables through a Kruskal–Wallis and verified with post hoc Bonferroni. The tumor volume was similar in both groups (EEA 11.92 cm³, -TCA 13.23 cm³). The mean follow-up in months was 39.9 for EEA and 43.94 for TCA, p = 0.76). The EEA group presented a higher visual improvement rate (41.96% vs. 25% for TCA, p < 0.0001, OR 7.7). Permanent DI was less frequent with EEA (29.20% vs. 67.40% for TCA, p < 0.0001, OR 0.2). CSF Leaks occurred more frequently with EEA (9.94% vs. 0.70% for TCA, p < 0.0001, OR 15.8). Recurrence rates were lower in the EEA group (EEA 15.50% vs. for TCA 21.20%, p = 0.04, OR 0.7). Our results demonstrate that, in selected cases, EEA for resection of craniopharyngiomas is associated with better results regarding visual preservation and extent of tumor resection. Postoperative CSF leak rates associated with EEA have improved compared to the historical series. The decision-making process should consider each person’s characteristics; however, it is noticeable that recent data regarding EEA justify its widespread application as a first-line approach in centers of excellence for skull base surgery.

Hands‐on dissections using cadaveric tissues for neuroanatomical education are not easily available in many educational institutions due to financial, safety, and ethical factors. Supplementary pedagogical tools, for instance, 3D models of anatomical specimens acquired with photogrammetry are an efficient alternative to democratize the 3D anatomical data. The aim of this study was to describe a technical guideline for acquiring realistic 3D anatomic models with photogrammetry and to improve the teaching and learning process in neuroanatomy. Seven specimens with different sizes, cadaveric tissues, and textures were used to demonstrate the step‐by‐step instructions for specimen preparation, photogrammetry setup, post‐processing, and display of the 3D model. The photogrammetry scanning consists of three cameras arranged vertically facing the specimen to be scanned. In order to optimize the scanning process and the acquisition of optimal images, high‐quality 3D models require complex and challenging adjustments in the positioning of the specimens within the scanner, as well as adjustments of the turntable, custom specimen holders, cameras, lighting, computer hardware, and its software. MeshLab® software was used for editing the 3D model before exporting it to MedReality® (Thyng, Chicago, IL) and SketchFab® (Epic, Cary, NC) platforms. Both allow manipulation of the models using various angles and magnifications and are easily accessed using mobile, immersive, and personal computer devices free of charge for viewers. Photogrammetry scans offer a 360° view of the 3D models ubiquitously accessible on any device independent of operating system and should be considered as a tool to optimize and democratize the teaching of neuroanatomy.

Background: Minimally invasive approaches to the anterior cranial fossa have evolved over the past few decades. The management of frontal epidural abscesses (EDAs) secondary to diffuse sinusitis in the pediatric population using minimally invasive techniques is scarcely reported in the literature. Herein, we report the utilization of a minimally invasive eyebrow approach for multidisciplinary concurrent evacuation of frontal EDA secondary to diffuse sinusitis and trephination of the frontal sinus in three pediatric patients. Case Reports: Three pediatric patients presented to the emergency room with severe headaches, visual changes, somnolence, and significant facial and periorbital swelling. Imaging revealed diffuse sinusitis with focal frontal epidural extension. In all cases, progressive clinical deterioration along with the radiographic findings mandated urgent surgical intervention. The eyebrow approach allowed for concomitant evacuation of the frontal EDA and trephination of the frontal sinus followed by functional endoscopic sinus surgery in the same setting. All patients tolerated the procedure well with complete resolution of their symptoms at the completion of antibiotic therapy and complete resolution of the EDA. Conclusion: The eyebrow approach is a minimally invasive technique that should be considered as part of the armamentarium in the management of select EDA in the pediatric population. It allows for multidisciplinary collaboration between neurosurgeons and otolaryngologists for concomitant evacuation of the EDA and trephination of the frontal sinus. This approach is a feasible, safe, and effective minimally invasive technique that can be employed for the management of EDA secondary to diffuse sinusitis in the pediatric population.