Intracranial electroencephalography (iEEG) can be performed using minimally invasive stereo-electroencephalography (SEEG) or by implanting subdural electrodes via a craniotomy or multiple burr holes. There is anecdotal evidence that SEEG is becoming more common in the United States, though this has yet to be quantified. To address this question, all SEEG and burr hole/craniotomy subdural iEEG procedures were extracted from the Centers for Medicare and Medicaid Services Part B data files for the years 2000-2016. National trends were compared over time. In 2016, SEEG became the most frequently performed intracranial monitoring procedure in the Medicare population, increasing from 28.8% of total cases in 2000 to 43.1% in 2016 (p = 0.02). The proportion of strip electrode cases (through burr holes) significantly declined, while the frequency of craniotomies for subdural grid placement did not significantly change. These data are consistent with a nationwide increase in the utilization of SEEG with a concomitant decline in burr hole placement of subdural strip electrodes in the United States. The factors driving these changes are unknown, but are likely due in part to the desire for minimally invasive surgical options.

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OBJECTIVEPostoperative cerebral venous sinus thrombosis (CVST) is an uncommon complication of posterior fossa surgery. The true incidence of and optimal management strategy for this entity are largely unknown. Herein, the authors report their institutional incidence and management experience of postoperative CVST after vestibular schwannoma surgery.METHODSThe authors undertook a retrospective review of all vestibular schwannoma cases that had been treated with microsurgical resection at a single institution from December 2011 to September 2017. Patient and tumor characteristics, risk factors, length of stay, surgical approaches, sinus characteristics, CVST management, complications, and follow-up were analyzed.RESULTSA total of 116 patients underwent resection of vestibular schwannoma. The incidence of postoperative CVST was 6.0% (7 patients). All 7 patients developed lateral CVST ipsilateral to the lesion. Four cases occurred after translabyrinthine approaches, 3 occurred after retrosigmoid approaches, and none occurred following middle cranial fossa approaches. Patients were managed with anticoagulation or antiplatelet therapy. Although patients were generally asymptomatic, one patient experienced intraparenchymal hemorrhage, epidural hemorrhage, and obstructive hydrocephalus, likely as a result of the anticoagulation therapy. However, all 7 patients had a modified Rankin scale score of 1 at the last follow-up.CONCLUSIONSPostoperative CVST is an infrequent complication, with an incidence of 6.0% among 116 patients who had undergone vestibular schwannoma surgery at one institution. Moreover, the management of postoperative CVST with anticoagulation therapy poses a serious dilemma to neurosurgeons. Given the paucity of reports in the literature and the low incidence of CVST, additional studies are needed to better understand the cause of thrombus formation and help to establish evidence-based guidelines for CVST management and prevention.

Meningiomas are among the most common intracranial pathological conditions, accounting for 36% of intracranial lesions treated by neurosurgeons. Although the majority of these lesions are benign, the classical categorization of tumors by histological type or World Health Organization (WHO) grade has not fully captured the potential for meningioma progression and recurrence. Many targeted treatments have failed to generate a long-lasting effect on these tumors. Recently, several seminal studies evaluating the genomics of intracranial meningiomas have rapidly changed the understanding of the disease. The importance of NF2 (neurofibromin 2), TRAF7 (tumor necrosis factor [TNF] receptor–associated factor 7), KLF4 (Kruppel-like factor 4), AKT1, SMO (smoothened), PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha), and POLR2 (RNA polymerase II subunit A) demonstrates that there are at least 6 distinct mutational classes of meningiomas. In addition, 6 methylation classes of meningioma have been appreciated, enabling improved prediction of prognosis compared with traditional WHO grades. Genomic studies have shed light on the nature of recurrent meningioma, distinct intracranial locations and mutational patterns, and a potential embryonic cancer stem cell–like origin. However, despite these exciting findings, the clinical relevance of these findings remains elusive. The authors review the key findings from recent genomic studies in meningiomas, specifically focusing on how these findings relate to clinical insights for the practicing neurosurgeon.

Adnexal masses in pregnancy are not commonly encountered. The majority of these masses are discovered incidentally during routine follow-up. However, some of these masses become symptomatic due to their size, location, and impingement of adjacent structures. Several diagnostic modalities can be utilized for the detection of adnexal masses with different sensitivity and specificity rates. The differential diagnosis of adnexal masses discovered during pregnancy is broad and includes both benign and malignant lesions. The management of such lesions has been a subject of debate for years with no consensus regarding the best management plan. Tumor size, site, and the trimester of mass detection are all crucial in management. In this account, we review adnexal masses discovered in pregnancy, the diagnostic modalities utilized for detecting these lesions, their differential diagnosis, and management strategies.

OBJECTIVECavernous sinus meningiomas are complex tumors that offer a perpetual challenge to skull base surgeons. The senior author has employed a management strategy for these lesions aimed at maximizing tumor control while minimizing neurological morbidity. This approach emphasizes combining “safe” tumor resection and direct decompression of the roof and lateral wall of the cavernous sinus as well as the optic nerve. Here, the authors review their experience with the application of this technique for the management of cavernous sinus meningiomas over the past 15 years.METHODSA retrospective analysis was performed for patients with cavernous sinus meningiomas treated over a 15-year period (2002–2017) with this approach. Patient outcomes, including cranial nerve function, tumor control, and surgical complications were recorded.RESULTSThe authors identified 50 patients who underwent subtotal resection via frontotemporal craniotomy concurrently with decompression of the cavernous sinus and ipsilateral optic nerve. Of these, 25 (50%) underwent adjuvant radiation to the remaining tumor within the cavernous sinus. Patients most commonly presented with a cranial nerve (CN) palsy involving CN III–VI (70%), a visual deficit (62%), headaches (52%), or proptosis (44%). Thirty-five patients had cranial nerve deficits preoperatively. In 52% of these cases, the neuropathy improved postoperatively; it remained stable in 46%; and it worsened in only 2%. Similarly, 97% of preoperative visual deficits either improved or were stable postoperatively. Notably, 12 new cranial nerve deficits occurred postoperatively in 10 patients. Of these, half were transient and ultimately resolved. Finally, radiographic recurrence was noted in 5 patients (10%), with a median time to recurrence of 4.6 years.CONCLUSIONSThe treatment of cavernous sinus meningiomas using surgical decompression with or without adjuvant radiation is an effective oncological strategy, achieving excellent tumor control rates with low risk of neurological morbidity.

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OBJECTIVEWith the continuous rise of health care costs, hospitals and health care providers must find ways to reduce costs while maintaining high-quality care. Comparing surgical and endovascular treatment of intracranial aneurysms may offer direction in reducing health care costs. The Value-Driven Outcomes (VDO) database at the University of Utah identifies cost drivers and tracks changes over time. In this study, the authors evaluate specific cost drivers for surgical clipping and endovascular management (i.e., coil embolization and flow diversion) of both ruptured and unruptured intracranial aneurysms using the VDO system.METHODSThe authors retrospectively reviewed surgical and endovascular treatment of ruptured and unruptured intracranial aneurysms from July 2011 to January 2017. Total cost (as a percentage of each patient’s cost to the system), subcategory costs, and potential cost drivers were evaluated and analyzed.RESULTSA total of 514 aneurysms in 469 patients were treated; 273 aneurysms were surgically clipped, 102 were repaired with coiling, and 139 were addressed with flow diverter placements. Middle cerebral artery aneurysms accounted for the largest portion of cases in the clipping group (29.7%), whereas anterior communicating artery aneurysms were most frequently involved in the coiling group (30.4%) and internal carotid artery aneurysms were the majority in the flow diverter group (63.3%). Coiling (mean total cost 0.25% ± 0.20%) had a higher cost than flow diversion (mean 0.20% ± 0.16%) and clipping (mean 0.17 ± 0.14%; p = 0.0001, 1-way ANOVA). Coiling cases cost 1.5 times as much as clipping and flow diversion costs 1.2 times as much as clipping. Facility costs were the most significant contributor to intracranial clipping costs (60.2%), followed by supplies (18.3%). Supplies were the greatest cost contributor to coiling costs (43.2%), followed by facility (40.0%); similarly, supplies were the greatest portion of costs in flow diversion (57.5%), followed by facility (28.5%). Cost differences for aneurysm location, rupture status, American Society of Anesthesiologists (ASA) grade, and discharge disposition could be identified, with variability depending on surgical procedure. A multivariate analysis showed that rupture status, surgical procedure type, ASA status, discharge disposition, and year of surgery all significantly affected cost (p < 0.0001).CONCLUSIONSFacility utilization and supplies constitute the majority of total costs in aneurysm treatment strategies, but significant variation exists depending on surgical approach, rupture status, and patient discharge disposition. Developing and implementing approaches and protocols to improve resource utilization are important in reducing costs while maintaining high-quality patient care.