Endoscopic Retrolabyrinthine Craniotomy for Exposure of the Trigeminal Nerve Root Entry Zone: Volumetric Analysis of Anatomic Exposure in the Cadaver.

BACKGROUND AND OBJECTIVES: Exposure of the root entry zone (REZ) of the trigeminal nerve (TN) for microvascular decompression is commonly obtained with a retrosigmoid approach, with or without endoscopic assistance. We hypothesized that adequate exposure of the TN REZ could be obtained through an endoscopic retrolabyrinthine (RL) approach. We aim to quantify exposure of the REZ of the TN using endoscopic RL approach, with and without drilling of the suprameatal tubercle of the internal auditory canal. METHODS: Surgical dissection was performed bilaterally on 3 embalmed cadaveric human heads at the anatomy laboratory of the House Institute. Heads were scanned for volumetric analysis using 3D Slicer software both before and after dissection. Extent of exposure was quantified in 2 ways: first, by assessment of the surgeon's ability to visualize 16 predetermined anatomic landmarks with the endoscope and second, we estimated the "working" area by placing fiducials under the fully endoscopic view and calculating the resultant 3D volume. RESULTS: Using the standard endoscopic RL approach, an average of 13.8 landmarks (range 12-16) was visualized. The estimated working volume exposed by the RL on each side of each head varied from 189.28 to 527.85 mm3. Drilling of the suprameatal tubercle provided both increases in landmark visualization and, on average, an additional 55 mm3 of working volume. CONCLUSION: The endoscopic RL approach is a viable alternative to the standard retrosigmoid approach. Potential advantages of the RL include a more lateral trajectory that minimizes the need for cerebellar retraction and a shorter working distance and shallower angle to the cerebellopontine angle. Potential disadvantages include longer surgery time, increased technical difficulty of exposure, and potential for cerebrospinal fluid leak and or hearing loss.

Comparison of Surgeons' Assessment of the Extent of Vestibular Schwannoma Resection with Immediate Post Operative and Follow-Up Volumetric MRI Analysis.

(1) Background: Incomplete excision of vestibular schwannomas (VSs) is sometimes preferable for facial nerve preservation. On the other hand, subtotal resection may be associated with higher tumor recurrence. We evaluated the correlation between intra-operative assessment of residual tumor and early and follow-up imaging. (2) Methods: The charts of all patients undergoing primary surgery for sporadic vestibular schwannoma during the study period were retrospectively reviewed. Data regarding surgeons' assessments of the extent of resection, and the residual size of the tumor on post-operative day (POD) one and follow-up MRI were extracted. (3) Results: Of 109 vestibular schwannomas meeting inclusion criteria, gross-total resection (GTR) was achieved in eighty-four, near-total (NTR) and sub-total resection (STR) in twenty-two and three patients, respectively. On follow up imaging, volumetric analysis revealed that of twenty-two NTRs, eight were radiographic GTR and nine were radiographic STR (mean volume ratio 11.9%), while five remained NTR (mean volume ratio 1.8%). Of the three STRs, two were radiographic GTR while one remained STR. Therefore, of eighteen patients with available later follow up MRIs, radiographic classification of the degree of resection changed in six. (4) Conclusions: An early MRI (POD#1) establishes a baseline for the residual tumor that may be more accurate than the surgeon's intraoperative assessment and may provide a beneficial point of comparison for long-term surveillance.

Malignant progression of cerebellopontine angle solitary fibrous tumors following radiation: illustrative case.

BACKGROUND: Intracranial solitary fibrous tumors (ISFTs) are rare mesenchymal tumors originating in the meninges and constitute a heterogeneous group of clinical and biological behavior. Benign histotypes, such as hemangiopericytomas are now considered as a cellular phenotypic variant of this heterogenous group of rare spindle-cell tumors. IFSTs are poorly recognized and remain a diagnostic challenge due to rarity and resemblance to other brain tumors. Previously, IFSTs were thought to pursue a slow, indolent, and nonaggressive course, however, a growing body of literature based on longer follow-up demonstrates an unpredictable clinical course and an uncertain diagnosis. OBSERVATIONS: A rare case report of malignant transformation of IFST following radiation therapy is reported. In this case a 60-year-old female who underwent gross total resection of the cerebellopontine angle tumor with histopathology consistent with solitary fibrous tumor followed by salvage stereotactic radiosurgery, presented with another recurrence after 2 years of surgery. The authors performed complete removal of the tumor with pathology now consistent with malignant solitary fibrous tumor. A recent follow-up magnetic resonance imaging did not show any recurrence or residual tumor, and the patient reports a generalized well-being. LESSONS: This report will help to understand the natural history and unusual clinical behavior of these intracranial tumors.

Endoscopic closure of the Eustachian tube orifice for refractory lateral skull base cerebrospinal fluid leak using autologous fat graft: illustrative case.

BACKGROUND: Rhinorrhea due to lateral skull base cerebrospinal fluid (CSF) leaks can be a challenge to manage. Multiple strategies exist for treating CSF leaks in this region including direct repair, posterior Eustachian tube packing, and CSF diversion. Endonasal closure of the Eustachian tube has been reported using cerclage and mucosal flaps. OBSERVATIONS: We present the first reported case of endoscopic autologous fat packing of the Eustachian tube orifice to repair a CSF leak. In this case a 42-year-old woman who underwent middle fossa meningioma resection 20 years ago presented with refractory CSF rhinorrhea despite blind sac closure of the ear canal. This persisted after CSF diversion and only resolved after endoscopic endonasal Eustachian tube closure described herein. LESSONS: This technique is simple to perform with minimal risk of morbidity. Eustachian tube orifice fat packing may be particularly useful for patients with refractory CSF rhinorrhea with low CSF pressure.

Safety and Efficacy of Hypofractionated Stereotactic Radiosurgery in Facial Nerve Schwannoma.

OBJECTIVE: In the current era of modern neurosurgery, the treatment strategies have been shifted to "nerve-preservation approaches" for achieving a higher facial and hearing function preservation rate following facial nerve tumors. We have conducted this novel report on determining the outcome of patients with facial nerve schwannomas (FNS) treated with hypofractionated stereotactic radiosurgery (hfSRS). PATIENTS: Retrospective chart review of a prospectively maintained database search was conducted. INTERVENTION: Patients who underwent hfSRS CyberKnife (Accuray Inc, Sunnyvale, CA, U.S.A.) for FNS were included. MAIN OUTCOME MEASURES: Outcomes consisted of tumor control, facial and hearing nerve function as graded by House-Brackmann and American Academy of Otolaryngology-Head and Neck Surgery recommendations, and adverse radiation effects. RESULTS: With an institutional board review approval, we retrospectively identified five patients with FNS (four intracranial [80%] and one extracranial [20%]) treated with hfSRS (2011-2019). Patients received definitive SRS in three patients (60.0%), whereas adjuvant to surgical resection in two patients (40.0%). A median tumor volume of 7.5 cm 3 (range, 1.5-19.6 cm 3 ) received a median prescription dose of 23.2 Gy (range, 21-25 Gy) administered in median of three fractions (range, three to five sessions). With a median radiographic follow-up of 31.4 months (range, 13.0-71.0 mo) and clinical follow-up of 32.6 months (range, 15.1-72.0 mo), the local tumor control was 100.0%. At the last clinical follow-up, the facial nerve function improved or remained unchanged House-Brackmann I-II in 80.0% of the patients, whereas the hearing nerve function improved or remained stable in 100.0% of the patients. Temporary clinical toxicity was observed in three patients (60.0%), which resolved. None of the patients developed adverse radiation effect. CONCLUSION: From our case series, hfSRS in FNS seems to be safe and efficacious in terms of local tumor control, and improved facial and hearing nerve function.

The Role of Intra-Operative Duplex Ultrasonography Following Translabyrinthine Approach for Vestibular Schwannoma.

Objective: Sigmoid sinus (SS) stenosis is a complication of translabyrinthine approach. Velocity changes in the SS measured by intra-operative doppler ultrasound may help in identifying patients at risk for sinus occlusion. Patients: SS velocity was measured using doppler ultrasound prior to opening dura and again prior to placement of the abdominal fat graft. Intervention: Data collected included: patient age, surgical side, sinus dominance, tumor volume, intra-operative doppler ultrasound measurements, post-operative venous sinus imaging, anticoagulation, and morbidities and mortalities. Main Outcome Measure: SS patency and velocity. Results: Eight patients were included in the analysis (22 to 69 years). Four had left-sided and four had right-sided craniotomies. Sigmoid sinuses were either right-side dominant or co-dominant. The mean velocity ± standard deviation (SD) prior to dura opening and abdominal fat packing was 23.2 ± 11.3 and 25.5 ± 13.9 cm/s, respectively, p = 0.575. Post-operative Magnetic Resonance Venography (MRV) imaging showed four sigmoid sinus occlusions; seven patients showed sigmoid sinus stenosis, and one internal jugular vein occlusion. One patient had post-operative Computed Tomography Venography (CTV) only. Of the four patients with MRV occlusions, CTVs were performed with three showing occlusion and all four-showing stenosis. One patient with internal jugular vein occlusion on MRV received warfarin anticoagulation. There was one cerebrospinal fluid leak requiring ear closure, one small cerebellar infarct, and one with facial nerve palsy (House-Brackman Grade 3). Conclusion: SS velocity changes before and after tumor resection were not predictive of sinus occlusion. We hypothesize that sinus occlusion may be caused by related factors other than thrombosis, such as external compression of the sinus secondary to abdominal fat grafting.

Predictors of hearing functional outcome following surgery for cerebellopontine angle meningioma.

OBJECTIVE: Cerebellopontine angle (CPA) meningiomas can affect hearing function and require expeditious treatment to prevent permanent hearing loss. The authors sought to determine the factors associated with functional hearing outcome in CPA meningioma patients treated with surgery and/or radiation therapy in the form of either stereotactic radiosurgery or stereotactic radiation therapy. METHODS: Consecutive patients with CPA meningiomas who had presented at our hospital from 2008 to 2018 were identified through retrospective chart review. Hearing function (as defined by pure tone average (PTA) and speech discrimination score (SDS) on Audiogram) was assessed before and after surgery for CPA meningioma. Audiograms with PTA > 50 dB and SDS < 69% were defined as poor hearing functional outcome. Multivariable Cox Proportional Hazards Regression Model was used to assess the associations between pre-operative hearing functional assessment and post-operative hearing functional outcomes. RESULTS: The study cohort included 31 patients (80.6% females, with a mean age of 61.3 ± 15.2 years) with a median clinical follow-up of 5 months (range: 1 week-98 months). The mean pre-operative PTA and SDS were 23.8 ± 11.2 dB and 64.4 ± 22.2% respectively. At the last visit, there was significant hearing recovery, with an improvement of 29.7 ± 18.0 dB (p < 0.001) and 87.6 ± 17.8% (p < 0.001) in PTA and SDS respectively. After adjusting for age, gender, tumor volume, location, and tumor classification, Multivariable Cox Proportional Hazards Regression Model was conducted which revealed that patients undergoing surgery through retro sigmoid approach [Hazards Ratio (HR): 32.1, 95% Confidence Interval (CI): 2.11-491.0, p = 0.01] and gross total resection (GTR) (HR: 2.99, 95% CI: 1.09-9.32, p = 0.05) had significantly higher risk of poor hearing functional outcome compared to petrosal approach and near/subtotal resection. Moreover, patients with poor preoperative hearing had 85% higher chance of poor hearing functional outcome postoperatively (HR: 0.15, 95%CI: 0.03-0.59, p = 0.007). CONCLUSION: Postoperative improvement in hearing is a reasonable expectation following surgery for CPA meningioma. Preoperative hearing, surgical approach and extent of surgical resection are predictive factors of postoperative hearing function outcome and can therefore aid in identification of patients at higher risk of hearing loss.

Safety of 3 Tesla Magnetic Resonance Imaging in Patients With Auditory Brainstem Implants.

OBJECTIVE: To evaluate the safety of 3 Tesla (T) magnetic resonance imaging (MRI) in patients with auditory brainstem implants (ABI) with the magnet removed at implantation and report incidence of complications. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary neurotology ambulatory practice. PATIENTS: Patients with diagnosis of Neurofibromatosis, type 2 (NF2) with functional ABIs. INTERVENTIONS: Observational recordings. MAIN OUTCOME MEASURES: Of the 89 patients meeting inclusion criteria, 7 patients underwent 3T MRI, with a total of 39 scans done. Three patients had 1 scan each, one patient had 4 scans, one patient had 5 scans, one patient had 6 scans, and one patient had 21 scans. The mean time between ABI placement and first 3 T scan was 118 ±â€Š73 months. The most common indication for imaging was surveillance of NF2 lesions. The most frequent scans were MRI brain (25.6%), followed by MRI of cervical (15%), thoracic (15%) and lumbar (15%) spine, and MRI IAC (8%). There were no reported complications for any of the scans. No scans were interrupted due to patient discomfort. There were no device malfunctions. CONCLUSIONS: 3 T MRIs are safe in patients with ABIs as long as the magnet is removed. It is recommended that the magnet be removed at the time of implantation in all NF2 patients, who require frequent surveillance.

End-to-Trunk Masseteric to Facial Nerve Transfer With Selective Neurectomy for Facial Reanimation.

OBJECTIVE: To examine functional outcomes following end-to-trunk masseteric to facial nerve transfer in patients with chronic flaccid facial paralysis. DESIGN: Retrospective chart review. SETTING: Tertiary-care private practice setting. PARTICIPANTS: Patients with complete unilateral facial paralysis of less than 24 months duration. INTERVENTIONS: Direct end-to-trunk masseteric to facial nerve anastomosis. OUTCOME MEASURES: Outcome measures included time to first movement, development of synkinesis, and an objective assessment of the resting tone and dynamic movement that was achieved. RESULTS: Patient age at the time of transfer ranged from 6 to 61. Follow-up ranged from 12 to 24 months. No patients had any perioperative complications. No patient experienced significant mass movement or synkinetic facial movement with chewing. No patient had worsened chewing or swallowing. Patients have not yet recovered significant resting tone. All patients achieved smile activity when biting down with a median (interquartile range) oral commissure excursion of 7.57 mm (5.19-9.94 mm), starting 3 to 5 months after transfer. CONCLUSIONS: End-to-trunk masseteric to facial nerve transfer is a safe and effective procedure. Patients had rapid reinnervation with good excursion and achieved a natural appearing smile. The rehabilitated smile appears better than that achieved with hypoglossal-facial nerve transfer. The procedure can be performed coincident with cross-facial nerve grafting, and in some cases may produce dynamic facial movement that obviates the need for free muscle transfer.

Matched Cohort Analysis of the Effect of the Facial Recess Approach on Cerebrospinal Fluid Leak After Translabyrinthine Surgery for Schwannoma.

OBJECTIVE: The facial recess approach during translabyrinthine surgery has been used to expose the eustachian tube (ET) for packing. We sought to determine the effect of this technique on the development of postoperative nasopharyngeal cerebrospinal fluid (CSF) leaks. PATIENTS: Cohorts of patients with cerebellopontine angle schwannomas who underwent a facial recess approach or no facial recess approach were matched based on tumor size. INTERVENTIONS: Translabyrinthine surgery for tumor resection. MAIN OUTCOME MEASURES: Postoperative CSF leaks were recorded and nasopharyngeal CSF leaks were utilized as the primary outcome measure. RESULTS: Using an exact matching protocol based on tumor size, 102 patients were included in each group (204 total, 111 female, 93 male). Overall, 9 patients (4.4%) demonstrated a postoperative nasopharyngeal CSF leak. Postoperative CSF rhinorrhea was noted in 3.9% of the group who underwent a facial recess approach for packing of the ET and 4.9% of the group who did not undergo a facial recess approach. This rate was not significantly different between groups (p = 0.99, Odds ratio: 0.79, 95% CI: 0.15-3.8). Secondary variables including age, tumor size, a diagnosis of NF2, and the packing material used were not significant predictors of nasopharyngeal CSF leaks. CONCLUSIONS: CSF rhinorrhea is infrequent after translabyrinthine surgery. The incidence of this complication is not affected by whether or not a facial recess approach is performed during surgery to pack the ET. Based on these data, use of this technique should be based on surgeon comfort and preference.

Clinical Significance of Middle Cerebellar Peduncle Ischemia After Translabyrinthine Vestibular Schwannoma Resection.

OBJECTIVE: To assess clinical symptoms, signs, and radiographic evolution of middle cerebellar peduncle (MCP) diffusion restriction (DR) abnormalities following vestibular schwannoma (VS) resection. STUDY DESIGN: Retrospective chart and imaging review. SETTING: Tertiary-referral neurotology and neurosurgery practice. PATIENTS: All consecutive patients who underwent translabyrinthine VS resection over a 2-year period (August 2017-May 2019). INTERVENTION: Translabyrinthine craniotomy for VS resection. MAIN OUTCOME MEASURES: Magnetic resonance imaging (MRI) obtained on postoperative day 1 were reviewed for DR within the pons and cerebellum, with 3 months follow-up MRI to assess for evolution of these vascular changes. RESULTS: Of the 31 patients who met inclusion criteria, MRI demonstrated MCP DR consistent with acute ischemia in 29% (9/31). Of those, two showed corresponding T2 signal abnormalities on follow up MRI consistent with cerebrovascular accident (CVA) within the MCP. Both had severe gait ataxia and dysmetria requiring acute rehabilitation admission and significantly larger tumors (p = 0.02). The remaining seven were asymptomatic, and DR abnormality resolved without lasting radiographic changes. Brainstem compression was present in 100% of patients with postoperative MCP DR (mean MCP ipsilateral:contralateral ratio 0.59 ±â€Š0.19), and 68.1% of those without (mean MCP ratio 0.71 ±â€Š0.25), a difference that was not statistically significant (p = 0.14). In the two patients with CVA, MCP asymmetry persisted, whereas the asymmetry resolved in all others. CONCLUSIONS: Asymptomatic acute MCP ischemia discovered incidentally does not require intervention. However, when the ischemic area is large and patients are symptomatic, especially if an acute rehabilitation admission is required, surgeons should suspect true CVA.

Auditory Brainstem Implant in Adult Patient With Cochlear Ossification From Otosclerosis.

OBJECTIVE: The objective is to describe auditory brainstem implantation in a case of extensive cochlear otosclerosis. PATIENT, INTERVENTION, AND RESULTS: A case is presented of a 65-year-old male with bilateral cochlear otosclerosis and profound sensorineural hearing loss. Imaging studies showed distorted cochlear anatomy bilaterally and ossification of cochlear ducts. He underwent successful placement of an auditory brainstem implant using a retrosigmoid craniotomy approach. CONCLUSIONS: Extensive cochlear otosclerosis may distort cochlear anatomy such that cochlear implantation is expected to have a poor outcome. Auditory brainstem implantation may be an additional treatment option in these patients.

Hypercoagulability in Vestibular Schwannoma Surgery.

OBJECTIVE: Patients with vestibular schwannoma who harbor a genetic predisposition for venous thromboembolism require special consideration when determining optimal therapeutic management. The primary objective of the current study was to provide recommendations on treatment of hypercoagulable patients with vestibular schwannoma through a case series and review of the literature. PATIENTS: Two patients who underwent resection of vestibular schwannomas. INTERVENTIONS: Surgical resection and diagnostic testing. MAIN OUTCOME MEASURES: Postoperative venous thromboses. RESULTS: One patient who underwent resection of vestibular schwannoma and suffered several postoperative thrombotic complications consistent with a clinical thrombophilia. One patient with known Factor V Leiden deficiency who underwent resection of vestibular schwannoma followed by postoperative chemoprophylaxis with a direct factor Xa inhibitor and experienced an uneventful postoperative course. CONCLUSIONS: In patients with a known propensity for venous thromboembolism, the skull base surgeon should consider nonsurgical management. If the patient undergoes surgical resection, we recommend careful effort to minimize trauma to the sigmoid sinus. In addition, the surgeon may consider retrosigmoid or middle fossa approaches. Best practice recommendations include the use of pneumatic compression devices, early ambulation, and consideration of postoperative prophylactic anticoagulation in patients with a known genetic predisposition.

Facial nerve management in patients with malignant skull base tumors.

INTRODUCTION: The course of the facial nerve through the cerebellopontine angle, temporal bone, and parotid gland puts the nerve at risk in cases of malignancy. In contrast to Bell's palsy, which presents with acute facial paralysis, malignancies cause gradual or fluctuating weakness. METHODS: We review malignancies affecting the facial nerve, including those involving the temporal bone, parotid gland, and cerebellopontine angle, in addition to metastatic disease. Intraoperative management of the facial nerve and long term management of facial palsy are reviewed. RESULTS: Intraoperative management of the facial nerve in cases of skull base malignancy may involve extensive exposure, mobilization, or rerouting of the nerve. In cases of nerve sacrifice, primary neurorrhaphy or interposition grafting may be used. Cranial nerve substitution, gracilis free functional muscle transfer, and orthodromic temporalis tendon transfer are management options for long term facial paralysis. CONCLUSION: Temporal bone, parotid gland, and cerebellopontine angle malignancies pose a tremendous risk to the facial nerve. When possible, the facial nerve is preserved. If the facial nerve is sacrificed, static and dynamic reanimation strategies are used to enhance facial function.

An extended release ciprofloxacin/dexamethasone hydrogel for otitis media.

OBJECTIVE: Otitis media and associated otorrhea are frequent complications following tympanostomy tube insertion; the most common otologic procedure performed in children in the United States. Current treatments include the administration of antibiotic or antibiotic/anti-inflammatory combination drops to the affected ear. Several studies have demonstrated that using an antibiotic/anti-inflammatory combination product is more effective than the use of antibiotics alone. However, administration of any drops through the tympanostomy tube is very difficult in children, and patient compliance can be an issue. Our group has developed a novel combination drug/hydrogel formulation for the treatment of otitis media/otorrhea that releases both ciprofloxacin and dexamethasone over a 2-3 week period. This has the potential to offer significant advantages over current treatments in use in the clinic. METHODS: The release of drugs from the combination hydrogel was validated in vitro over the desired time frame and the activity of the released drugs was monitored via assays to confirm retention of full activity throughout the dissolution period. The safety of the ciprofloxacin/dexamethasone hydrogel and its inactive excipients was evaluated through in vivo otic toxicity studies in guinea pigs, including hearing tests, gross microscopy, and cytocochleogram analysis. RESULTS: Extended release of both drugs was demonstrated in vitro and antibiotic/anti-inflammatory activities were retained. The hydrogel components and its excipients did not cause adverse reactions in animals, demonstrating safety of the hydrogel combination in vivo. CONCLUSION: The studies presented lay the groundwork for extended release middle ear hydrogel formulations that are capable of safely releasing combinations of active pharmaceutical agents over a desired period of time. This would be more advantageous than therapeutics that are currently used in the clinic for the treatment of otitis media/otorrhea associated with tympanostomy tube insertion.

American Neurotology Society, American Otological Society, and American Academy of Otolaryngology - Head and Neck Foundation Guide to Enhance Otologic and Neurotologic Care During the COVID-19 Pandemic.

: This combined American Neurotology Society, American Otological Society, and American Academy of Otolaryngology - Head and Neck Surgery Foundation document aims to provide guidance during the coronavirus disease of 2019 (COVID-19) on 1) "priority" of care for otologic and neurotologic patients in the office and operating room, and 2) optimal utilization of personal protective equipment. Given the paucity of evidence to inform otologic and neurotologic best practices during COVID-19, the recommendations herein are based on relevant peer-reviewed articles, the Centers for Disease Control and Prevention COVID-19 guidelines, United States and international hospital policies, and expert opinion. The suggestions presented here are not meant to be definitive, and best practices will undoubtedly change with increasing knowledge and high-quality data related to COVID-19. Interpretation of this guidance document is dependent on local factors including prevalence of COVID-19 in the surgeons' local community. This is not intended to set a standard of care, and should not supersede the clinician's best judgement when managing specific clinical concerns and/or regional conditions.Access to otologic and neurotologic care during and after the COVID-19 pandemic is dependent upon adequate protection of physicians, audiologists, and ancillary support staff. Otolaryngologists and associated staff are at high risk for COVID-19 disease transmission based on close contact with mucosal surfaces of the upper aerodigestive tract during diagnostic evaluation and therapeutic procedures. While many otologic and neurotologic conditions are not imminently life threatening, they have a major impact on communication, daily functioning, and quality of life. In addition, progression of disease and delay in treatment can result in cranial nerve deficits, intracranial and life-threatening complications, and/or irreversible consequences. In this regard, many otologic and neurotologic conditions should rightfully be considered "urgent," and almost all require timely attention to permit optimal outcomes. It is reasonable to proceed with otologic and neurotologic clinic visits and operative cases based on input from expert opinion of otologic care providers, clinic/hospital administration, infection prevention and control specialists, and local and state public health leaders. Significant regional variations in COVID-19 prevalence exist; therefore, physicians working with local municipalities are best suited to make determinations on the appropriateness and timing of otologic and neurotologic care.

Effect of Vestibular Schwannoma Size and Nerve of Origin on Posterior External Auditory Canal Sensation: A Prospective Observational Study.

OBJECTIVE: Posterior external auditory canal (EAC) hypesthesia (Hitselberger's sign) has been previously described to occur in all vestibular schwannomas (1966) but has not been studied since. We hypothesized that sensory loss may be related to tumor size and sought to determine if this clinical sign could predict preoperative characteristics of vestibular schwannomas, intraoperative findings, and/or surgical outcomes. STUDY DESIGN: Prospective observational study. SETTING: Tertiary referral center. PATIENTS: Twenty-five consecutive patients who underwent surgery for vestibular schwannoma. INTERVENTION: Patients were tested for the presence of EAC hypesthesia or anesthesia. MAIN OUTCOME MEASURES: Preoperative, intraoperative, and postoperative findings were recorded, including facial nerve function, hearing function, tumor size, tumor nerve of origin, and extent of resection. RESULTS: Twelve patients (48%) demonstrated either posterior EAC hypesthesia (11 patients) or anesthesia (1 patient). Sensory loss was a significant predictor of size (tumor maximal diameter) (p = 0.004). Median tumor diameter was 1.7 cm in the cohort with intact sensation versus 2.9 cm in the cohort with sensory loss. Patients with sensory loss were also significantly more likely to be associated with a superior vestibular nerve origin tumor (p = 0.01). Preoperative sensory loss did not significantly predict postoperative facial outcome (p = 0.10). CONCLUSION: Neurological exam findings may be overlooked in the workup of brain tumors. Posterior EAC hypesthesia is a predictor of tumor size and superior vestibular nerve origin. These findings may have implications for patient selection, particularly with the middle cranial fossa approach. Furthermore, given this relationship with tumor size, this clinical biomarker should be studied as a potential predictor of tumor growth.

Effect of Anatomic Segment Involvement on Stereotactic Radiosurgery for Facial Nerve Schwannomas: An International Multicenter Cohort Study.

BACKGROUND: Facial nerve schwannomas are rare, challenging tumors to manage due to their nerve of origin. Functional outcomes after stereotactic radiosurgery (SRS) are incompletely defined. OBJECTIVE: To analyze the effect of facial nerve segment involvement on functional outcome for these tumors. METHODS: Patients who underwent single-session SRS for facial nerve schwannomas with at least 3 mo follow-up at 11 participating centers were included. Preoperative and treatment variables were recorded. Outcome measures included radiological tumor response and neurological function. RESULTS: A total of 63 patients (34 females) were included in the present study. In total, 75% had preoperative facial weakness. Mean tumor volume and margin dose were 2.0 ± 2.4 cm3 and 12.2 ± 0.54 Gy, respectively. Mean radiological follow-up was 45.5 ± 38.9 mo. Progression-free survival at 2, 5, and 10 yr was 98.1%, 87.2%, and 87.2%, respectively. The cumulative proportion of patients with regressing tumors at 2, 5, and 10 yr was 43.1%, 63.6%, and 63.6%, respectively. The number of involved facial nerve segments significantly predicted tumor progression (P = .04). Facial nerve function was stable or improved in 57 patients (90%). Patients with involvement of the labyrinthine segment of the facial nerve were significantly more likely to have an improvement in facial nerve function after SRS (P = .03). Hearing worsened in at least 6% of patients. Otherwise, adverse radiation effects included facial twitching (3 patients), facial numbness (2 patients), and dizziness (2 patients). CONCLUSION: SRS for facial nerve schwannomas is effective and spares facial nerve function in most patients. Some patients may have functional improvement after treatment, particularly if the labyrinthine segment is involved.

Options and strategies for hearing restoration in pediatric neurofibromatosis type 2.

PURPOSE: In this article, we will review the mechanisms and natural history of hearing loss in neurofibromatosis type 2 (NF2) and discuss the hearing outcomes with different rehabilitation options. METHODS: Review of the published literature. RESULTS: NF2 is a rare autosomal dominant syndrome characterized by vestibular schwannomas and other intracranial and spinal tumors. Bilateral vestibular schwannomas are the hallmark of the disease which occur in 90 to 95% of the patients. As a result, hearing loss will eventually occur in almost all NF2 patients. Deafness can occur from tumor progression or from treatment of vestibular schwannomas and is among the most debilitating aspects of NF2. A number of surgical and non-surgical rehabilitation options are available for these patients including cochlear and auditory brainstem implants. The audiologic outcomes with surgical rehabilitation options have been variable but most patients are able to achieve sound awareness and benefit from auditory cues in lip reading. CONCLUSION: Early identification and treatment of NF2 patients can help in achieving better hearing outcomes in the pediatric population. An increasing number of NF2 patients are receiving open set word understanding with refinement in surgical techniques.