Faculty Bibliography

BACKGROUND:Direct carotid-cavernous sinus fistulas (dCCFs) are high flow arteriovenous shunts between the internal carotid artery and the cavernous sinus. Recently, we have used the pipeline embolization device (PED) to treat dCCFs. METHODS:We describe our experience treating patients with dCCFs in whom the PED was placed as the primary treatment modality. RESULTS:Five patients with dCCFs were treated with PEDs deployed in the ipsilateral internal carotid artery spanning the fistula. All patients also underwent either adjunctive transvenous or transarterial embolization. The PED served both as the primary treatment modality and as a scaffold that facilitated safe and efficacious transvenous embolysate administration by altering the flow dynamics through the fistula and providing a physical barrier that protected the internal carotid artery. No intraoperative or perioperative complications occurred. One of the five patients exhibited complete angiographic resolution of the fistula immediately after the procedure. The remaining four patients experienced complete obliteration of the fistula without additional treatment, which suggests that the PED induced alteration promoted thrombosis of the fistula. Therefore, 100% of patients in this series exhibited complete and durable obliteration of the fistula and complete resolution of symptoms following treatment. CONCLUSIONS:We believe that use of the PED to treat dCCFs may be a safe and efficacious strategy that facilitates parent vessel protection during transvenous embolization. Furthermore, the flow alterations induced by the PED may promote thrombosis of incompletely occluded fistulas. This is the largest reported series of non-iatrogenic dCCFs treated with use of the PED as the primary initial treatment strategy.

OBJECTIVE:Recent large-cohort sequencing studies have investigated the genomic landscape of meningiomas, identifying somatic coding alterations in NF2, SMARCB1, SMARCE1, TRAF7, KLF4, POLR2A, BAP1, and members of the PI3K and Hedgehog signaling pathways. Initial associations between clinical features and genomic subgroups have been described, including location, grade, and histology. However, further investigation using an expanded collection of samples is needed to confirm previous findings, as well as elucidate relationships not evident in smaller discovery cohorts. METHODS:Targeted sequencing of established meningioma driver genes was performed on a multiinstitution cohort of 3016 meningiomas for classification into mutually exclusive subgroups. Relevant clinical information was collected for all available cases and correlated with genomic subgroup. Nominal variables were analyzed using Fisher's exact tests, while ordinal and continuous variables were assessed using Kruskal-Wallis and 1-way ANOVA tests, respectively. Machine-learning approaches were used to predict genomic subgroup based on noninvasive clinical features. RESULTS:Genomic subgroups were strongly associated with tumor locations, including correlation of HH tumors with midline location, and non-NF2 tumors in anterior skull base regions. NF2 meningiomas were significantly enriched in male patients, while KLF4 and POLR2A mutations were associated with female sex. Among histologies, the results confirmed previously identified relationships, and observed enrichment of microcystic features among "mutation unknown" samples. Additionally, KLF4-mutant meningiomas were associated with larger peritumoral brain edema, while SMARCB1 cases exhibited elevated Ki-67 index. Machine-learning methods revealed that observable, noninvasive patient features were largely predictive of each tumor's underlying driver mutation. CONCLUSIONS:Using a rigorous and comprehensive approach, this study expands previously described correlations between genomic drivers and clinical features, enhancing our understanding of meningioma pathogenesis, and laying further groundwork for the use of targeted therapies. Importantly, the authors found that noninvasive patient variables exhibited a moderate predictive value of underlying genomic subgroup, which could improve with additional training data. With continued development, this framework may enable selection of appropriate precision medications without the need for invasive sampling procedures.

OBJECTIVE:Granular cell tumors (GCTs), pituicytomas, and spindle cell oncocytomas are rare, nonfunctioning pituitary tumors sharing positive staining of thyroid transcription factor 1. We present our series, the first single-institutional report with long-term surgical follow-up of all 3 tumor types. METHODS:Our institutional pathology database was queried for these 3 pathologic diagnoses. Clinical records were assessed for clinical presentation, preoperative and postoperative endocrine status, tumor location on imaging, surgical characteristics, pathology results, and tumor recurrence. RESULTS:Data were analyzed for 4 patients with GCTs, 4 with pituicytomas, and 3 with spindle cell oncocytomas. The most common symptoms at presentation were vision changes (64%), headache (55%), endocrine abnormalities (55%), and fatigue (46%). GCTs were the only subtype to present exclusively in the infundibulum and the only subtype in our series to be treated with a transcranial transsylvian approach to resection (n = 2). In our study, in contrast to other reports, estimated blood loss was less than 300 mL in all patients. Imaging confirmed gross total resection in all 11 cases with no known recurrences at a mean (standard deviation) follow-up of 4.7 (3.7) years. CONCLUSIONS:We present a single-institution series of rare thyroid transcription factor 1-staining posterior pituitary tumors of the sellar region. Key novel findings include gross total resection with no tumor recurrence at nearly 5 years of mean follow-up and no cases of excess or uncontrolled blood loss. Our findings reinforce the observation that GCTs present in the suprasellar space.

BACKGROUND:Indications for reconstruction of the common carotid artery (CCA) include trauma, iatrogenic injury, neoplastic growth (such as invasive neck carcinomas), postoperative infection, and cervical carotid aneurysm. Although various techniques and conduits have been described, the clinical scenario may preclude the use of the most commonly used grafts. We describe a case using a superficial femoral artery (SFA) interposition graft to repair the CCA and review the available literature, highlighting the feasibility of this technique for carotid artery reconstruction. CASE DESCRIPTION/METHODS:A patient aged 51 years presented with a ruptured mycotic CCA pseudoaneurysm that developed in the setting of a pharyngeal-carotid fistula. Because of the presence of a pharyngeal-carotid fistula and active infection within the vessel wall, endovascular treatment of the pseudoaneurysm was not feasible, and open surgical correction was required to repair the fistulous connection. Furthermore, owing to the extensive soft tissue infection, the use of a synthetic or venous autograft conduit for repair of the artery was contraindicated. Therefore, we harvested a segment of the SFA and used it as an interposition graft to reconstruct the diseased CCA, achieving an excellent anatomic and clinical result. CONCLUSIONS:This case highlights the feasibility of using an SFA interposition graft for short-segment CCA reconstruction, which can provide significant utility in the setting of a hostile operative field due to prior infection or radiation.

BACKGROUND:Ruptured aneurysms causing intraventricular hemorrhage (IVH) are associated with high morbidity. The presence of blood that completely fills the fourth ventricle (cast fourth ventricle, CFV) is thought to be particularly ominous, but studies documenting the outcome of such cases are lacking. OBJECTIVE:To investigate the outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) and CFV. METHODS:We reviewed 406 patients enrolled in the Barrow Ruptured Aneurysm Trial (BRAT, NCT01593267, clinicaltrials.gov); 238 patients with aSAH and IVH were identified, and imaging was reviewed for the presence of CFV. Outcome was evaluated at the 1-yr follow-up. A poor outcome was defined as modified Rankin Scale score >2. RESULTS:CFV was identified in 25 patients. Admission Glasgow Coma Score was lower in CFV patients, 7.8 versus 11.5 (P < .001). At discharge and the 1-yr follow-up, patients with CFV had a greater risk of a poor outcome (P < .001 and P = .002, respectively). In a subgroup analysis of 79 patients with IVH and initial Glasgow Coma Score ≤ 8, almost 50% of the patients with IVH but without CFV had made a good recovery versus 7% of patients with CFV (odds ratio [OR] 15, P = .002). On multivariate analysis, CFV was a greater predictor of a poor prognosis at 1 yr post-aSAH than Hunt and Hess grade >3 (6.4 OR vs 2.9 OR [P < .001], respectively). CONCLUSION:The presence of CFV is a predictor of poor outcome in patients with aSAH. When compared to other patients with IVH and aSAH, CFV is a stronger predictor of a poor outcome than a poor Hunt and Hess Grade.

Fractionated CyberKnife radiosurgery (CKRS) treatment for acoustic neuromas may reduce the risk of long-term radiation toxicity to nearby critical structures compared to that of single-fraction radiosurgery. However, tumor control rates and clinical outcomes after CKRS for acoustic neuromas are not well described. We retrospectively reviewed all acoustic neuroma patients treated with CKRS (2004-2011) in a prospectively maintained clinical and radiographic database. Treatment failure, the need for additional surgical intervention, was evaluated using Kaplan-Meier analysis. For 119 treated patients, median values were 49 months (range, 6-133 months) of follow-up, 1.6 cm³ (range, 0.02-17 cm³) tumor volume, and 18 Gy (range, 13-25 Gy) prescribed dose delivered in 3 fractions (range, 1-5 fractions). Thirty-five of 59 patients (59%) with pre-radiosurgery serviceable hearing (American Academy of Otolaryngology-Head and Neck Surgery class A or B) maintained serviceable hearing at the last audio follow-up (median, 21 months). Two of 111 patients (2%) with facial nerve function House-Brackmann (HB) grade ≤3 progressed to HB grade >3 after radiosurgery. Koos grade IV was predictive of radiographic tumor growth after radiosurgery compared to grades I to III (p = 0.02). Treatment failure occurred in 9 of 119 patients (8%); median time to failure was 29 months (range, 4-70 months). The actuarial rates of tumor control at 1, 3, 5, and 7 years were 96%, 94%, 88%, and 88%, respectively. CKRS affords effective tumor control for acoustic neuromas with an acceptable rate of hearing preservation. Further studies are needed to compare CKRS to single-fraction radiosurgery for acoustic neuromas.