Patel, Neil

Objectives To present a rare case of traumatic facial neuroma involving the geniculate ganglion and review relevant literature. Patient Thirty-year-old man. Intervention Microsurgical resection via combined mastoid-middle fossa approach with great auricular nerve interpositional graft. Main Outcome Measures Patient demographics and pre- and postoperative facial nerve function. Results A 30-year-old man with a reported history of prior Bell's palsy developed progressive complete (House–Brackmann VI) right facial paralysis following blunt trauma. Imaging was strongly suggestive of a geniculate ganglion hemangioma. As the patient had no spontaneous improvement in his poor facial function over the course of 9 months, he underwent resection of the facial nerve lesion with great auricular nerve graft interposition via a combined mastoid-middle fossa approach. Histopathology demonstrated disorganized fascicles, with axonal clustering reminiscent of sprouting/regeneration following trauma. No cellular proliferation or vascular malformation was present. Conclusion Traumatic facial nerve neuromas can occur following temporal bone trauma and can closely mimic primary facial nerve tumors. Akin to the management of geniculate ganglion hemangioma and schwannoma, preoperative facial function largely dictates if and when surgery should be pursued.

Objectives This video describes the surgical indications, relevant anatomy, and surgical steps of routine translabyrinthine surgery for gross total resection of sporadic vestibular schwannoma. Design The procedure is presented through a surgical instructional video. Setting The surgery took place at tertiary skull base referral center. Parcipant A 47-year-old patient reported with nonserviceable hearing, frequent episodes of vertigo, recurrent severe headache, and a small unilateral right sided vestibular schwannoma. Results Gross total resection with preservation of facial nerve function was achieved. Conclusion This instructional video documents the surgical steps and relevant anatomy for translabyrinthine resection of vestibular schwannoma.The link to the video can be found at: https://youtu.be/CJ2vKMLs7aI.

Introduction Optimal management of vestibular schwannoma (VS) demands involvement of an experienced multidisciplinary team. As the number of training programs in neurotology and skull base neurosurgery continues to rise, ensuring that trainees are capable of evidence-based decision-making and treatment, whether microsurgical or radiosurgical, is of paramount importance. The purpose of this study is to characterize the landscape of neurotologic and neurosurgical fellowship training programs in North America, with special reference to VS management. Methods A 64-item web-based survey assessing VS practice trends was devised by members of the North American Skull Base Society (NASBS) Research Task Force and distributed electronically to NASBS membership via SurveyMonkey as a cross-sectional study. Participation was entirely voluntary and there was no remuneration for survey completion. The survey link was active from November 29 to December 14, 2016. Results Of 719 members of the NASBS who were emailed a survey link, a total of 57 were returned (8%) completed surveys. Of all respondents, 51 (89%) claimed to have formal training in skull base neurosurgery or neurotology. Thirty-three respondents (65%) were skull base neurosurgeons while the remainder were neurotologists (n = 18; 35%). Institutions with fellowship programs tended to have a higher surgical, radiosurgical, and overall case volume than those with a residency program alone. However, 20% of respondents at institutions with fellowship programs reported evaluating less than 50 new diagnoses of VS per year and 12% reported a surgical case volume of less than 10 cases per year. Conclusion As the number of skull base training programs expands, it is our duty to ensure that trainees gain sufficient experience to enter independent practice with the ability to exercise informed decision-making and safely perform VS surgery and radiosurgery. In the current training climate, implementing multidisciplinary care models, formalized training requirements, and emerging surgical simulators will support the development of minimum proficiencies in VS care.

Objective: To describe audiometric outcomes following stereotactic radiosurgery (SRS) for jugular paraganglioma (JP). Study Design: Retrospective review. Setting: Tertiary referral center. Patients: Patients with pretreatment serviceable hearing (American Academy of Otolaryngology—Head and Neck Surgery [AAO-HNS] Class A or B) and serial post-SRS audiometric follow-up who underwent Gamma Knife SRS for JP between 1990 and 2017. Intervention(s): Gamma Knife SRS. Main Outcome Measures: Progression to nonserviceable hearing; correlation between baseline hearing and treatment parameters with audiometric outcomes. Results: Of 85 patients with JP who underwent SRS during the study period, 35 (66% female, median age 53) had pretreatment serviceable hearing and serial post-treatment audiometry available for review. Median tumor volume at the time of treatment was 7,080 mm3, median cochlear point dose was 5.8 Gy (interquartile range [IQR] 4.1 to 7.3 Gy), and median marginal and maximum tumor doses were 16 and 32 Gy, respectively. After a median follow-up of 37 months (IQR 16 to 77 mo), the median change in pure-tone average and speech discrimination score in the treated ear was −1.2 dB HL/yr (IQR −4.5 to 0.3) and 0%/yr (IQR 0–3.5%), compared with 0.07 dB HL/yr (IQR −0.03 to 0.12) and 0 %/yr (IQR 0 to 0%) in the contralateral untreated ear. Seven patients developed nonserviceable hearing (AAO-HNS Class C or D) at a median of 13.2 months following SRS (IQR 4.8 to 24 mo). Among those who maintained serviceable hearing, median audiometric follow-up was 42 months (IQR 18 to 77 mo). The Kaplan–Meier estimated rates of serviceable hearing at 1, 3, and 5 years following SRS were 91%, 80%, and 80%, respectively. Sixty percent of patients with pulsatile tinnitus who underwent SRS experienced varying levels of symptomatic improvement following treatment. Conclusion: The short- and intermediate-term risk of progression to nonserviceable hearing following SRS for JP is low. Data regarding the impact of cochlear dose from the vestibular schwannoma literature should not be freely applied to JP, since the impact of SRS parameters on hearing preservation seems to be less significant.

ObjectiveDemonstrate the association of radiographic dural enhancement with increased tumor adherence at the porus acusticus, which may influence completeness of resection and facial nerve outcome.Study DesignCase series with chart review.SettingAcademic referral center.Subjects and MethodsA total of 205 consecutive patients with histopathologically confirmed vestibular schwannoma (VS) were evaluated. Patients with tumors exhibiting dural enhancement on postgadolinium T1‐weighted magnetic resonance imaging were identified and compared with matched controls. Completeness of resection, intraoperative details, and facial nerve outcomes were analyzed.ResultsExcluding strictly intracanalicular tumors (n = 32, 16%) and those with NF2 (n = 10, 4.9%), the presence of dural enhancement was radiographically confirmed in 16 (9.8%) cases. Paired analysis did not reveal significant baseline differences between cases and controls. Subtotal resection was performed in 5 (31%) of the 16 patients with tumors exhibiting dural enhancement, in contrast to 1 (3%) of the matched controls (P =. 01). Four (25%) demonstrated increased tumor adherence at the porus acusticus intraoperatively, compared with 1 control (3%, P =. 04). Long‐term facial nerve function was similar between cases and controls (81% vs 84% House‐Brackmann I‐II function, P = 1.00).ConclusionDural enhancement is present in approximately 10% of extracanalicular VS. Dural enhancement at the porus acusticus may represent hypervascularity, dural reaction, or infiltration, and portends increased tumor adherence and greater likelihood of subtotal resection to preserve facial nerve function. To our knowledge, this is the first series that reports the prevalence of this phenomenon in VS and the potential surgical implications. Recognition preoperatively may be valuable toward patient counseling.

ObjectiveTo characterize disease presentation and outcomes following surgical treatment of parotid malignancies with occult temporal bone facial nerve (FN) involvement.Study DesignCase series with chart review.SettingTertiary academic referral center.Subjects and MethodsThirty consecutive patients (mean age 58 years; 77% men) who underwent surgery for parotid malignancies with occult perineural involvement of the intratemporal FN were included. Primary outcome measures included margin status and recurrence.ResultsThe mean duration of clinical follow‐up was 49 months, and the most common presenting symptom was FN paresis (n = 23; 77%) followed by pain (n = 15; 50%). To obtain a proximal FN margin, 27 patients (90%) underwent mastoidectomy, and 3 patients (10%) had lateral temporal bone resection. The intratemporal FN margin was cleared in 26 patients (87%), most commonly in the mastoid segment (60%). Adjuvant therapy was given in 25 patients (83%). Ten patients (33%) experienced locoregional (4; 13%) and/or distant (8; 27%) recurrence at a median of 19 months (mean 26, 2–54 months) following surgery. Locoregional failure was significantly more common in cases with a positive intratemporal FN margin (66% vs 8%; P =. 045). Overall 1‐, 3‐, and 5‐year disease‐specific survival rates were 83%, 79%, and 72%, respectively.ConclusionsPerineural invasion of the intratemporal FN by parotid malignancy is uncommon. Normal preoperative FN function does not preclude histopathologic involvement. Temporal bone FN exploration should be considered when a positive margin is encountered at the stylomastoid foramen, as failure to do so is associated with an increased rate of locoregional recurrence.