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OBJECTIVESphenoorbital meningioma (SOM) is a unique skull base tumor, characterized by infiltrative involvement and hyperostosis primarily of the lesser wing of sphenoid bone, with frequent involvement of the orbital compartment. SOM often manifests with proptosis and visual impairment. Surgical technique and outcome are highly variable among studies reported in the literature. The authors present a single-surgeon experience with SOM.METHODSA retrospective review of a prospectively maintained institutional database was performed. A blinded imaging review by 2 study team members was completed to confirm SOM, after which chart review was carried out to capture demographics and outcomes. All statistical testing was completed using JMP Pro version 14.1.0, with significance defined as p < 0.05.RESULTSForty-seven patients who underwent surgery between 2000 and 2017 were included. The median age at surgery was 47 years (range 36–70 years), 81% of patients were female, and the median follow-up was 43 months (range 0–175 months). All operations were performed via a frontotemporal craniotomy, orbitooptic osteotomy, and anterior clinoidectomy, with extensive resection of all involved bone and soft tissue. Preoperatively, proptosis was noted in 44 patients, 98% of whom improved. Twenty-eight patients (60%) had visual deficits before surgery, 21 (75%) of whom improved during follow-up. Visual field defect other than a central scotoma was the only prognostic factor for improvement in vision on multivariate analysis (p = 0.0062). Nine patients (19%) had recurrence or progression during follow-up.CONCLUSIONSSOM is a unique skull base tumor that needs careful planning to optimize outcome. Aggressive removal of involved bone and periorbita is crucial, and proptosis and visual field defect other than a central scotoma can improve after surgery.

AbstractCerebral amyloidomas, characterized by localized amyloid deposits in the nervous system in the absence of systemic disease, are rare. These typically consist of immunoglobulin light chain (AL)-type, predominantly lambda. Trigeminal nerve involvement is exceptionally rare with only 21 previously reported cases, three with bilateral disease. We report two additional cases of amyloid localized to Meckel’s cave with secondary involvement of the trigeminal nerves bilaterally, with protein characterization by mass spectrometry. The patients, both females, 39 and 49-years-old, respectively, presented with the insidious onset of progressive trigeminal neuropathy, including pain and numbness with sensory loss, refractory to medical therapy. One patient experienced bilateral symptoms. Magnetic resonance imaging demonstrated abnormal thickening and contrast enhancement along Meckel’s cave bilaterally in both cases. The clinical differential diagnosis included benign neoplasms and inflammatory disorders. At the time of biopsy, the trigeminal nerve was noted to be enlarged and multinodular in one case and associated with abnormal soft tan tissue in the other case. Microscopically, the nerve biopsies showed extensive Congo red-positive amyloid deposits. Liquid chromatography tandem mass spectrometry demonstrated that the amyloid was of (AL)-type in both cases (AL [kappa] in one case and AL [lambda] in the other). After extensive evaluation, there was no evidence of systemic involvement. Both patients received localized radiotherapy for their refractory symptoms. One patient has stable symptomatology and imaging. No follow-up is available for the other patient.

OBJECTIVERadiation dose to the cochlea has been proposed as a key prognostic factor in hearing preservation following stereotactic radiosurgery (SRS) for vestibular schwannoma (VS). However, understanding of the predictive value of cochlear dose on hearing outcomes following SRS for patients with non-VS tumors of the lateral skull base (LSB) is incomplete. The authors investigated rates of hearing loss following high-dose SRS in patients with LSB non-VS lesions compared with patients with VS.METHODSPatients with LSB meningioma or jugular paraganglioma and serviceable pretreatment hearing who underwent SRS treatment during 2007–2016 and received a modiolus dose > 5 Gy were included in a retrospective cohort study, along with a similarly identified control group of consecutive patients with sporadic VS.RESULTSSixteen patients with non-VS tumors and a control group of 43 patients with VS met study criteria. Serviceable hearing, defined as American Academy of Otololaryngology–Head and Neck Surgery class A/B, was maintained in 13 non-VS versus 23 VS patients (81% vs 56%, p = 0.07). All 3 instances of hearing loss in non-VS patients were observed in cerebellopontine angle (CPA) meningiomas. Non-VS with preserved hearing had a median modiolus dose of 6.9 Gy (range 5.7–19.2 Gy), versus 7.4 Gy (range 5.4–7.6 Gy) in those patients with post-SRS hearing loss (p = 0.53). Sporadic VS patients received an overall median modiolus point-dose of 6.8 Gy (range 5.4–11.7 Gy).CONCLUSIONSThe modiolus dose threshold of 5 Gy does not predict hearing loss in patients with non-VS tumors undergoing SRS, suggesting that dosimetric parameters derived from VS may not be applicable to this population. Differential rates of hearing loss appear to vary by pathology, with paragangliomas and petroclival meningiomas demonstrating decreased risk of hearing loss compared to CPA meningiomas that may directly compress the cochlear nerve similarly to VS.

Abstract BACKGROUND Surgical resection is typically cited as the optimal treatment of patients with Spetzler-Martin Grade I-II arteriovenous malformation (AVM). OBJECTIVE To report our experience with single-fraction stereotactic radiosurgery (SRS) for Spetzler-Martin Grade I-II AVM. METHODS A prospectively maintained registry was reviewed for patients with nonsyndromic Spetzler-Martin Grade I-II AVM having SRS from 1990 to 2011. Patients with <24 mo of follow-up or prior radiotherapy/SRS were excluded, resulting in a study population of 173 patients. Actuarial analysis was performed using the Kaplan-Meier method, and Cox proportional hazards modeling was performed with excellent outcomes (obliteration without new deficits) as the dependent variable. RESULTS Median post-SRS follow-up was 68 mo (range, 24-275). AVM obliteration was achieved in 132 (76%) after initial SRS. Eleven additional patients achieved obliteration after repeat SRS for an overall obliteration rate of 83%. The rate of obliteration was 60% at 4 yr and 78% at 8 yr. Post-SRS hemorrhage occurred in 7 patients (4%), resulting in 3 minor deficits (2%) and 1 death (<1%). Radiation-induced complications occurred in 5 patients (3%), resulting in minor deficits only. One hundred and thirty-seven patients (79%) had excellent outcomes at last follow-up. CONCLUSION SRS is a safe and effective treatment for patients with Spetzler-Martin Grade I-II AVM. Selection bias is likely a contributing factor to explain the superior outcomes generally noted in reported series of microsurgery for patients with low grade AVM.

Objective: The treatment paradigm for jugular paraganglioma (JP) has changed considerably over time with the wider adoption of stereotactic radiosurgery (SRS). To the best of the authors’ knowledge, there are no published studies that use validated patient-reported outcome measures to ascertain quality of life (QoL) outcomes following SRS for JP when used in single or combined modality treatment regimens. Study Design: Cross-sectional survey. Setting: Tertiary referral center. Patients: Adult patients with JP treated with primary SRS or SRS following primary surgery between 1990 and 2017. Interventions(S): Surgery and/or Gamma Knife SRS. Main Outcome Measures: Global and treatment-related QoL and differences in QoL based on treatment approach. Results: Sixty-nine surveys were distributed and a total of 26 completed surveys were received (38% response rate). Among respondents, the median age at SRS was 53 years and 16 of the 26 patients (62%) were female. Median follow-up was 97 months. Nineteen patients (73%) were treated with primary SRS or staged SRS following intentional subtotal resection (STR; hereafter referred to as “staged SRS”), while the remainder (n = 7, 27%) were treated with SRS for recurrent JP. Median physical and mental health QoL PROMIS-10 T-scores regardless of treatment strategy were 39.8 and 38.8, respectively, while median SF36 physical and mental component subscores were similar to national averages and non-tumor controls. When comparing general physical and mental health QoL scores, there was no significant difference between patients treated with primary or staged SRS and those treated with SRS for recurrent JP. However, age-adjusted swallowing function among patients treated with primary or staged SRS was better than in those patients treated with SRS for recurrent JP (p = 0.05). Conclusions: Patients treated with primary or staged SRS for JP tend to exhibit better swallowing outcomes than those treated with SRS for recurrent JP. However, the majority of overall and disease-specific quality of life measures were not different between groups. Based on the low incidence of new cranial neuropathy following SRS, it is likely that initial surgical morbidity is the primary contributor to this outcome. Disease-specific overall quality of life measures, akin to those already used for other benign skull base tumors, are necessary to better gauge physical and mental health outcomes following treatment for JP. Though limited by small sample size, this represents the first study to gauge QoL outcomes following treatment for JP.

Objectives Determine the effect of endoscopic skull base surgery (ESBS) on long‐term olfactory outcomes after surgery. Methods An English‐language search was conducted using the Cochrane, MEDLINE, Scopus, and Embase databases from January 2000 to October 2017 for adult patients undergoing ESBS with subjective and objective olfaction outcomes. Two authors independently examined articles to identify those meeting inclusion criteria. Studies examining objective olfactory outcomes after ESBS were included in the meta‐analysis. A random‐effects meta‐analysis of patients undergoing sellar and parasellar ESBS was conducted to compare preoperative and postoperative olfactory outcomes using the University of Pennsylvania Smell Identification Test (UPSIT) and Cross‐Cultural Smell Identification Test (CCSIT). Results Among 339 eligible articles, 29 articles met inclusion criteria. Twenty‐five of these focused on sellar and parasellar tumors. Individual articles not meeting criteria for meta‐analysis were qualitatively reported. Meta‐analysis showed there was no difference in preoperative and postoperative olfactory function after sellar and parasellar ESBS based on the UPSIT (five studies, mean difference [MD] = −1.03; 95% CI: −3.98, 1.93; P = .50) and the CCIST (three studies, MD = −0.77; 95% CI: −3.03, 1.49; P = .50). A pooled overall meta‐analysis revealed similar results (eight studies, effect size = −0.30; 95% CI: −0.79, 0.18; P = .22). However, heterogeneity for all meta‐analyses was high ( I 2 > 95%, P < .01), suggesting significant variation in the included studies. Conclusions Based on published objective olfaction outcomes after sellar and parasellar ESBS, there was no significant difference between preoperative and postoperative olfaction. Further prospective studies using validated objective measures of olfaction are required to improve our understanding on this subject. Level of Evidence 2a Laryngoscope , 129:1998–2007, 2019

Abstract BACKGROUND Patients with persistent or recurrent Cushing disease (CD) after prior transsphenoidal surgery require further treatment to reduce the disease's metabolic consequences. OBJECTIVE To assess patient outcomes after stereotactic radiosurgery (SRS) for persistent or recurrent CD from adrenocorticotropin hormone (ACTH)-secreting pituitary adenomas and propose a management algorithm. METHODS Retrospective review of 38 patients without prior radiation treatment having SRS for ACTH-secreting pituitary adenomas from 1990 to 2015. Favorable outcome was defined as biochemical remission and tumor growth control. Patients were evaluated separately if they underwent bilateral adrenalectomy (Adx). RESULTS Twenty patients (53%) were treated with Adx and SRS (median margin dose, 25 Gy) and 18 patients (47%) received SRS alone (median margin dose, 22.5 Gy). Median follow-up after SRS was 76 mo. Of patients undergoing Adx, 18/20 (90%) had a favorable outcome. Two patients (10%) had tumor growth requiring additional treatment. A favorable outcome was achieved in 13/18 patients (72%) having SRS alone (median, 14 mo; interquartile range, 8-23). Five patients (28%) required additional treatment due to persistent hypercortisolemia (n = 4) or hypercortisolemia and tumor growth (n = 1). Favorable outcomes were more frequent in the Adx and SRS group at 1 yr (100% vs 33%; P < .001) and 3 yr (100% vs 62%; P < .01), but no different at 5 yr (88% vs 77%; P = .63). CONCLUSION SRS was effective for patients with persistent or recurrent CD. Patients with mild to moderate CD can be safely managed with SRS alone; patients with severe CD should be considered for Adx with either concurrent SRS or SRS performed at a later date if tumor growth occurs.

Abstract BACKGROUND Stereotactic radiosurgery (SRS) is a common treatment modality for vestibular schwannoma (VS), with a role in primary and recurrent/progressive algorithms. At our institution, routine magnetic resonance imaging (MRI) is obtained at 6 and 12 mo following SRS for VS. OBJECTIVE To analyze the safety and financial impact of eliminating the 6-mo post-SRS MRI in asymptomatic VS patients. METHODS A prospectively maintained SRS database was retrospectively reviewed for VS patients with 1 yr of post-treatment follow-up, 2005 to 2015. Decisions at 6-mo MRI were binarily categorized as routine follow-up vs clinical action —defined as a clinical visit, additional imaging, or an operation as a direct result of the 6-mo study. RESULTS A total of 296 patients met screening criteria, of whom 53 were excluded for incomplete follow-up and 8 for NF-2. Nine were reimaged prior to 6 mo due to clinical symptoms. Routine 6-mo post-SRS MRI was completed by 226 patients (76% of screened cohort), following from which zero instances of clinical action occurred. When scaled using national insurance database-derived financials—which estimated the mean per-study charge for MRI of the brain with and without contrast at $1767—the potential annualized national charge reduction was approximated as $1 611 504. CONCLUSION For clinically stable VS, 6-mo post-SRS MRI does not contribute significantly to management. We recommend omitting routine MRI before 12 mo, in patients without new or progressive neurological symptoms. If extrapolated nationally to the more than 100 active SRS centers, thousands of patients would be spared an inconvenient, nonindicated study, and national savings in health care dollars would be on the order of millions annually.

Abstract The suprameatal tubercle is a variable prominence of the posterior aspect of the petrous part of the temporal bone located above the internal acoustic meatus. An enlarged suprameatal tubercle (EST) may present an obstacle during posterior fossa operations, including microvascular decompression (MVD). In this video we present the case of a 55-yr-old woman with 2 yr of medically refractory left V2-3 typical trigeminal neuralgia. Magnetic resonance imaging (MRI) was suspicious for a compressive superior cerebellar artery (SCA) loop, and negative for any other pathological findings. A left retrosigmoid craniotomy was performed, and upon initial exploration, only the most proximal, superior aspect of the trigeminal nerve was unobscured by an EST. The EST was subsequently removed using the ultrasonic aspirator with bone cutting attachment, allowing full visualization of the nerve from root entry zone (REZ) to Meckel's cave. Inferiorly, a small EST remnant was left to protect the VII-VIII complex. An MVD was performed using Teflon felt to elevate the SCA loop off the REZ and nerve, which was then fully explored, to ensure complete decompression. The patient recovered well with resolved trigeminal neuralgia and no new deficit. EST is a rare anatomic variant, with potentially significant implications for visualization of structures superior and deep to the internal acoustic canal, including the trigeminal REZ and nerve. Resection of the tubercle is safe, and recommended where it markedly obstructs the operative corridor. Care should be taken to wax the drilled surface of the petrous temporal bone and minimize incumbent risk of cerebrospinal fluid leak. Informed consent was appropriately documented and verified as outlined by our institutional guidelines.