Lane, John I.

Objective: Evaluate prevalence and pattern of occipital pneumatization (OP). Patients: Individuals with imaging evidence of OP on computed tomography (CT). Intervention(s): High resolution CT scans of the temporal bone. Main Outcome Measure: The prevalence and pattern of OP on 1000 CT scans performed at a large academic healthcare system. Results: OP had a prevalence of 11.8% (n = 118) while occipital condyle pneumatization occurred in only 0.3%. Occipital air cells were right-sided in 27.1% (n = 32), left-sided in 51.7% (n = 61), and bilateral in 21.2% (n = 25), and OP was contiguous with the occipitomastoid suture. In cases of unilateral OP, the contralateral jugular foramen demonstrated relative enlargement ( p = 0.006), but a direct association could not be established. Conclusions: The occipital bone is an accessory site of skull base pneumatization in 11.8% of the population undergoing temporal bone CT, while air cell extension into the occipital condyle occurs more rarely. These occipital air cells have a left-sided predilection and are always in direct proximity to the occipitomastoid suture, suggesting developmental egress from the mastoid. OP is a normal variant and lacks features of craniocervical pneumatization, which is a rare disorder.

Objective: To date, less than 150 cases of middle ear adenomatous neuroendocrine tumors (MEANTs) have been reported in the English literature. The objective of this study was to provide a contemporary analysis of these rare lesions and develop a consensus-driven staging system. Study Design: Multi-institutional retrospective histopathologic, radiologic, and clinical review. Setting: Six tertiary referral centers. Patients: Thirty-two patients with pathologically confirmed MEANT. Intervention: Surgical resection, adjuvant therapy. Main Outcome Measures: Clinical manifestations, outcomes, staging system. Results: Patients commonly presented with progressive conductive or mixed hearing loss (90%), aural fullness (50%), and tonal tinnitus (46%). Pulsatile tinnitus (16%), carcinoid syndrome (4%), and facial nerve paresis (4%) were less commonly observed. MEANTs frequently mimicked temporal bone paraganglioma (31%) and cholesteatoma (15%) at presentation. According to a novel T/N/M/S staging system (S = secretory tumor) proposed herein, there were 6 (19%) T1, 19 (59%) T2, and 7 (22%) T3 MEANTs. T3 tumors were significantly more likely to undergo subtotal or near total resection compared with lower staged tumors secondary to adherence to critical neurovascular structures such as the petrous internal carotid artery and facial nerve (p = 0.027). Patients with T3 MEANTs were more likely to experience multiple recurrences, require adjuvant therapy with a somatostatin analogue, or develop permanent facial nerve paresis compared with lower staged tumors. At last follow up, no patients with T1 MEANTs had developed recurrence, whereas 37% (7/19) of patients with T2 MEANT and 57% (4/7) of patients with T3 MEANT experienced either disease recurrence after gross total resection (GTR) or regrowth of known residual tumor requiring additional surgery at a median duration of 72 months (95% CI, 24–84). Conclusions: Patients with MEANTs can present with nonspecific symptomatology that overlaps with more commonly encountered middle ear lesions. MEANT exhibits a proclivity for recurrence according to T-stage and long-term clinical follow up is necessary, particularly for advanced stage tumors.

ObjectivesPrimary skull base lymphoma (PSBL) represents a rare manifestation of extranodal lymphoma. Presenting with nonspecific symptomatology and imaging findings, PSBL often masquerades as more common cranial base pathology and thus can present a diagnostic challenge. The objectives of this study were to characterize the manifestations and clinical outcomes of PSBL.Study DesignCase series and chart review.SettingTertiary referral center.Subjects and MethodsReview of 48 patients with PSBL treated between 1994 and 2016.ResultsThe median age at diagnosis was 60 years. Diffuse large B‐cell lymphoma comprised the most common subtype (56%). Presenting symptoms included diplopia (52%), trigeminal hypesthesia (38%), headache (29%), facial nerve weakness (25%), B‐symptoms (fevers, night sweats, and/or weight loss) (25%), and hearing loss (21%). Discrete lesions commonly mimicked meningioma, schwannoma, and nasopharyngeal carcinoma. Diffuse lesions imitated neurosarcoidosis, granulomatosis with polyangiitis, and carcinomatosis meningitis. Only 26% of all initial clinical evaluations suspected lymphoma. The combination of restricted diffusion on diffusion‐weighted imaging, an absence of flow voids or surrounding hyperostosis, bony erosion and/or marrow signal replacement, and heterogeneous contrast enhancement facilitated delineation between PSBL and common skull base pathology. Cerebrospinal fluid (CSF) analysis was diagnostic of lymphoma in 24% of cases. Lymphoma within CSF portended significantly worse overall survival (85% vs 18% at 3‐years; P <. 001).ConclusionA history significant for multiple cranial nerve palsies, B‐symptoms, and imaging findings inconsistent with common skull base pathology should raise suspicion for PSBL. CSF analysis in the setting of PSBL can provide diagnostic and prognostic value for patients.

Objective(1) Assess 3‐dimensional volumetric growth of untreated sporadic vestibular schwannomas (VSs) in a large cohort of patients treated with conservative observation. (2) Compare volumetric and conventional linear diameter measurements for detecting tumor growth.Study DesignCase series with chart review.SettingTertiary skull base referral center.Subjects and MethodsPatients with sporadic VS who elected initial conservative treatment with at least 2 serial magnetic resonance imaging (MRI) scans were included. Tumor volume was determined with 3‐dimensional segmentation of MRI sequences. The volumetric threshold for tumor growth was an increase ≥20% from baseline tumor volume. Tumor size based on linear diameter was assessed with the 1995 American Academy of Otolaryngology—Head and Neck Surgery Foundation guidelines for VS outcome reporting, with growth defined as an increase ≥2 mm.ResultsA total of 361 patients were included with a median radiologic follow‐up of 4.1 years (interquartile range [IQR], 2.5‐6.8). At diagnosis, 232 VSs (64%) were purely intracanalicular, and 129 (36%) extended into the cerebellopontine angle. The median baseline tumor volume was 0.161 cm3 (IQR, 0.054‐0.418). Overall, 69% of tumors demonstrated volumetric growth at a median of 1.1 years (IQR, 0.6‐2.1) after initial MRI. In contrast, based on linear measurement assessment, 48% of tumors demonstrated growth at a median of 1.8 years (IQR, 0.8‐3.1) from first MRI scan. Disequilibrium, facial hypoesthesia, aural fullness, initial tumor size, and nonincidental diagnosis were associated with tumor growth.ConclusionThree‐dimensional volumetric assessment of VS provides a more sensitive measure of tumor growth when compared with linear diameter assessment. Through volumetric analysis, the current study revealed that a significant proportion of VSs demonstrate growth during observation.

Background: Gadolinium-enhanced T1-weighted magnetic resonance imaging (MRI) (T1WI) is the conventional imaging technique of choice to detect vestibular schwannoma (VS) recurrence or regrowth, despite suboptimal specificity secondary to enhancing postoperative changes. Furthermore, recent concerns regarding the accumulation of gadolinium in body tissues have led for a call to reduce the number of contrast-enhanced examinations. The objective of the current study is to evaluate the diagnostic accuracy of high-resolution noncontrast (three-dimensional [3D] T2) MRI relative to gadolinium-enhanced T1WI in the detection of VS recurrence after resection. Methods: Following Institutional Review Board approval, 13 consecutive postoperative patients with VS recurrence or regrowth were identified from a prospectively maintained clinical database in which recurrence was determined by progression on serial postoperative MRI examination. Three blinded neuroradiologists retrospectively evaluated a total of 41 postoperative MRI examinations from these patients using only gadolinium-enhanced T1WI and 3D T2 MRI for recurrence or regrowth. Interobserver agreement, differences in detection between the two sequences, and the sensitivity and specificity of 3D T2 MRI were assessed. Results: Fifteen of the 41 postoperative MRIs demonstrated progression, as determined by examiner consensus on the gadolinium-enhanced T1WI. Agreement, measured using Krippendorff's alpha, was 0.82 for the 3D T2 images and 0.83 for the contrast-enhanced T1WI. All the three examiners demonstrated no difference in the detection of progression between the two sequences (McNemar's test p values 0.69 for examiner 1, 0.63 for examiner 2, and 0.99 for examiner 3). The sensitivity of 3D T2 was 0.78 (CI 0.60–0.96), while the specificity was 0.94 (CI 0.86–1.00). Conclusion: Noncontrast high-resolution 3D T2 MRI seems sufficient to assess for recurrence or regrowth after VS resection. The results of this study have implications for reducing cost, time, and adverse events associated with gadolinium administration in this population requiring serial follow-up examinations. These promising, yet preliminary findings warrant confirmation with a larger prospective cohort of patients.

Objective: To report the presentation, diagnosis, management, and convalescence of labyrinthine sequestrum (LS) and summarize all previously published cases. Patient(s): Eleven-year-old female with LS. Intervention(s): Multidisciplinary diagnostic evaluation and treatment. Main Outcome Measures: Imaging and laboratory findings, medical and surgical treatment. Results: We describe a case of LS secondary to medically recalcitrant suppurative otitis media in an 11-year-old female and review all eight previously reported cases. The index patient presented after 6 months of otitis media, profound unilateral hearing loss, with symptoms suggesting meningitis. Temporal bone CT demonstrated marked bony destruction of the left otic capsule. Gadolinium-enhanced MRI showed an enhancing process with evidence of meningitis and subdural empyema. The patient was treated with surgical debridement and culture directed antibiotic therapy. Posttreatment imaging showed resolution of intracranial infection with fibrous bony healing of the otic capsule resembling fibrous dysplasia. Conclusion: LS is a rare form of labyrinthitis characterized by centrifugal destruction of the otic capsule. The current index case highlights the importance of combined medical and surgical treatment and describes for the first time in the literature the fibrous ossification of the otic capsule following disease resolution.