Single-cell multi-omic analysis of the vestibular schwannoma ecosystem uncovers a nerve injury-like state

Vestibular schwannomas (VS) are benign tumors that lead to significant neurologic and otologic morbidity. How VS heterogeneity and the tumor microenvironment (TME) contribute to VS pathogenesis remains poorly understood. In this study, we perform scRNA-seq on 15 VS, with paired scATAC-seq (n = 6) and exome sequencing (n = 12). We identify diverse Schwann cell (SC), stromal, and immune populations in the VS TME and find that repair-like and MHC-II antigen-presenting SCs are associated with myeloid cell infiltrate, implicating a nerve injury-like process. Deconvolution analysis of RNA-expression data from 175 tumors reveals Injury-like tumors are associated with larger tumor size, and scATAC-seq identifies transcription factors associated with nerve repair SCs from Injury-like tumors. Ligand-receptor analysis and in vitro experiments suggest that Injury-like VS-SCs recruit myeloid cells via CSF1 signaling. Our study indicates that Injury-like SCs may cause tumor growth via myeloid cell recruitment and identifies molecular pathways that may be therapeutically targeted.

Relationship between clinical measures of hearing and clinical measures of vestibular function

PURPOSE

Patients often have basic audiometry (BA) but not objective diagnostic tests of the vestibular system (VNG) when complaining of symptoms of a vestibular disorder. The relationship of BA results to VNG results is unknown. This study sought to determine if BA scores are related to impaired VNG scores.

MATERIALS AND METHODS

We reviewed electronic medical records at a tertiary care center, for patients seen between 2015 and 2021 who had had both a BA and a VNG (n = 651). BA subtests were pure tone averages, word recognition, and tympanogram. VNG subtests were cervical vestibular evoked myogenic potentials, Dix-Hallpike maneuvers, and bi-thermal caloric tests. All tests were summarized as normal/abnormal.

RESULTS

More subjects had abnormal BA than abnormal VNG scores. Age but not sex was significantly related to abnormal scores. High BP was a significant comorbidity in 15 % of the sample, more in patients with abnormal than normal VNG scores. Although the abnormal BA and abnormal VNG were significantly related, pure tone averages and tympanogram scores were not related to VNG subtests. Abnormal word recognition with both ears combined was significantly related to normal and abnormal bi-thermal caloric tests.

CONCLUSIONS

If the clinician needs to know of any VNG impairment, in general, then performing a BA without a VNG might suffice. If the clinician needs information about the details of possible vestibular impairment, then a VNG should be performed.

Rationale for the Development of a Novel Clinical Grading Scale for Postoperative Facial Nerve Function: Results of a Multidisciplinary International Working Group

OBJECTIVE

The objective of the current study was to present the results of an international working group survey identifying perceived limitations of existing facial nerve grading scales to inform the development of a novel grading scale for assessing early postoperative facial paralysis that incorporates regional scoring and is anchored in recovery prognosis and risk of associated complications.

STUDY DESIGN

Survey.

SETTING

A working group of 48 multidisciplinary clinicians with expertise in skull base, cerebellopontine angle, temporal bone, or parotid gland surgery.

RESULTS

House-Brackmann grade is the most widely used system to assess facial nerve function among working group members (81%), although more than half (54%) agreed that the system they currently use does not adequately estimate the risk of associated complications, such as corneal injury, and confidence in interrater and intrarater reliability is generally low. Simplicity was ranked as the most important attribute of a novel postoperative facial nerve grading system to increase the likelihood of adoption, followed by reliability and accuracy. There was widespread consensus (91%) that the eye is the most critical facial region to focus on in the early postoperative setting.

CONCLUSIONS

Members were invited to submit proposed grading systems in alignment with the objectives of the working group for subsequent validation. From these data, we plan to develop a simple, clinically anchored, and reproducible staging system with regional scoring for assessing early postoperative facial nerve function after surgery of the skull base, cerebellopontine angle, temporal bone, or parotid gland.

Quality of Life After Modified Rambo Ear Canal Closure in Pediatric and Adult Patients

OBJECTIVE

To present the surgical and quality of life (QOL) outcomes of patients who underwent blind sac closure of the external auditory canal (EAC) via a modified Rambo approach.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary academic referral center.

METHODS

All patients who underwent EAC closure with a modified Rambo approach between 2015 and 2021 were evaluated. Complication rates, QOL estimations from a validated survey, and subjective cosmetic reports were analyzed.

RESULTS

Thirty-five ears were closed in 31 patients. The most common indication for surgery was related to cochlear implantation and cochlear malformation or cholesteatoma (31.4%). No case involved an immediate complication requiring revision surgery, and 4 ears (11.4%) were suspected of having cholesteatoma within the surgical cavity at a mean 28.6-month follow-up. Adults (≥18 years) had significantly higher QOL scores than children in the medical resource subscale of the Chronic Ear Survey (P < .01), and patients undergoing concurrent EAC closure and skull base tumor removal scored higher than others (P = .04). Females reported higher cosmetic scores than males (P = .04). QOL and cosmetic scores compared favorably to previously published data involving the management of otologic disease.

CONCLUSIONS

Ear canal closure can be a useful technique for select adult and pediatric patients. Patient and surgeon concerns regarding QOL and cosmesis in ear canal closure should be explored prior to employing this surgical technique, though the present data suggest that the modified Rambo approach to closure is generally associated with reasonable outcomes in both areas.

Monopolar Cautery Use in Pediatric Cochlear Implant Users

OBJECTIVES

To determine the incidence and impact of monopolar cautery use in a cohort of pediatric cochlear implant (CI) users.

STUDY DESIGN

Case series from a retrospective chart review and a systematic review of the literature.

SETTING

Tertiary academic referral center.

METHODS

CI patient charts from 2012 to 2021 were reviewed from a single pediatric hospital system to determine if monopolar cautery was used during a subsequent surgical procedure. In addition, a systematic review of the literature was performed to identify additional, relevant patients. Postoperative CI function was the primary outcome measure.

RESULTS

In total, 190 patients underwent a surgical procedure following cochlear implantation in a single pediatric hospital system. Fifteen patients (7.9%) and 17 distinct surgical procedures were identified in which monopolar cautery was used. Seven of these 17 cases (41.2%) involved the head and neck, and 10 were performed below the clavicles. No patients experienced a device failure or a decline in CI performance following surgery. A systematic review identified an additional 4 patients who underwent a surgery that used monopolar cautery following cochlear implantation, and no change in CI function was identified.

CONCLUSIONS

The present study adds additional support to the notion that monopolar cautery does not necessarily injure CI functionality. While the most risk adverse strategy when planning a surgical procedure for a CI patient is to avoid monopolar cautery use altogether, the use of cautery should not immediately be associated with implant dysfunction.

Approach to Cochlear Implantation in Patients With Ventriculoperitoneal Shunts

OBJECTIVE

To evaluate the safety and outcomes of cochlear implantation (CI) in patients with ventriculoperitoneal (VP) shunts to inform clinical practice.

STUDY DESIGN

Historical cohort study.

SETTING

Tertiary referral centers.

METHODS

A multi-institutional historical cohort of patients with VP shunts and CI was identified and analyzed.

RESULTS

A total of 46 patients (median age 8 years [interquratile range, IQR: 2-46]) with VP shunts and CI were identified. Of these, 41 (89%) patients had a VP shunt prior to CI. Based on institutional preference and individual patient factors, CI was performed contralateral to a pre-existing VP shunt in 24 of these 41 cases (59%) and ipsilateral in 17 (41%). Furthermore, pre-CI relocation of the VP shunt was performed in 3 cases (7%), and 2 patients (5%) underwent planned revision of their VP shunt concurrent with CI. In total, 2 of 27 pediatric patients (7%) required unanticipated revision shunt surgery, both contralateral to CI device placement, given VP shunt malfunction. One of 19 adult patients (5%) required shunt revision during CI due to shunt damage noted intraoperatively. Among 43 patients with available follow-up, 38 (88%) are regular CI users, with a median consonant-nucleus vowel-consonant word: score of 58% (IQR: 28-72).

CONCLUSION

CI can be performed at low risk, either contralateral or ipsilateral, to a VP shunt, and does not mandate shunt revision in most cases. Additional considerations regarding CI receiver-stimulator placement are necessary with programmable shunts to mitigate device interaction. Preoperative planning, including coordination of care with neurosurgery, is important to achieving optimal outcomes.

Effects of Age on Delayed Facial Palsy After Otologic Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES

To report 4 cases of delayed facial palsy (DFP) after pediatric middle ear (ME) surgery and systematically review and analyze the associated literature to evaluate the effects of age on DFP etiology, management, and prognosis.

METHODS

Systematic review of PubMed, Cochrane Library, and Embase for articles related to DFP after cochlear implantation (CI) was performed. These articles were assessed for level of evidence, methodological limitations, and number of cases. Meta-analysis was performed to assess the effects of age on DFP incidence. Furthermore, a comprehensive list of all pediatric DFP cases after otologic surgery was assembled through a multi-institutional retrospective review and systematic review of the literature.

RESULTS

Twenty-nine articles fit the criteria for inclusion in the meta-analysis. The incidence of DFP after CI was 0.23% and 1.01% for pediatric and adult cases, respectively. This difference was statistically significant (P < .001, odds ratio 4.36). Twenty-three cases, adding to the 4 presented herein, were suitable for a comprehensive list. The mean age was 6.9 years. Average postoperative day of paresis onset was 5.4, with an average maximum House-Brackmann grade of 3.5. All patients obtained full facial recovery after an average of 23.5 days.

CONCLUSIONS

The systematic review demonstrates that DFP after pediatric CI is rare and occurs at a significantly lower rate than in adults, further supporting the viral reactivation hypothesis of DFP. The prognosis for pediatric DFP after otologic surgery is excellent, with a high rate of full recovery in a short time frame. However, steroid administration can be considered.

LEVEL OF EVIDENCE

IIa.

Predicting surgical decision-making in vestibular schwannoma using tree-based machine learning

OBJECTIVE

Vestibular schwannomas (VSs) are the most common neoplasm of the cerebellopontine angle in adults. Though these lesions are generally slow growing, their growth patterns and associated symptoms can be unpredictable, which may complicate the decision to pursue conservative management versus active intervention. Additionally, surgical decision-making can be controversial because of limited high-quality evidence and multiple quality-of-life considerations. Machine learning (ML) is a powerful tool that utilizes data sets to essentialize multidimensional clinical processes. In this study, the authors trained multiple tree-based ML algorithms to predict the decision for active treatment versus MRI surveillance of VS in a single institutional cohort. In doing so, they sought to assess which preoperative variables carried the most weight in driving the decision for intervention and could be used to guide future surgical decision-making through an evidence-based approach.

METHODS

The authors reviewed the records of patients who had undergone evaluation by neurosurgery and otolaryngology with subsequent active treatment (resection or radiation) for unilateral VS in the period from 2009 to 2021, as well as those of patients who had been evaluated for VS and were managed conservatively throughout 2021. Clinical presentation, radiographic data, and management plans were abstracted from each patient record from the time of first evaluation until the last follow-up or surgery. Each encounter with the patient was treated as an instance involving a management decision that depended on demographics, symptoms, and tumor profile. Decision tree and random forest classifiers were trained and tested to predict the decision for treatment versus imaging surveillance on the basis of unseen data using an 80/20 pseudorandom split. Predictor variables were tuned to maximize performance based on lowest Gini impurity indices. Model performance was optimized using fivefold cross-validation.

RESULTS

One hundred twenty-four patients with 198 rendered decisions concerning management were included in the study. In the decision tree analysis, only a maximum tumor dimension threshold of 1.6 cm and progressive symptoms were required to predict the decision for treatment with 85% accuracy. Optimizing maximum dimension thresholds and including age at presentation boosted accuracy to 88%. Random forest analysis (n = 500 trees) predicted the decision for treatment with 80% accuracy. Factors with the highest variable importance based on multiple measures of importance, including mean minimal conditional depth and largest Gini impurity reduction, were maximum tumor dimension, age at presentation, Koos grade, and progressive symptoms at presentation.

CONCLUSIONS

Tree-based ML was used to predict which factors drive the decision for active treatment of VS with 80%–88% accuracy. The most important factors were maximum tumor dimension, age at presentation, Koos grade, and progressive symptoms. These results can assist in surgical decision-making and patient counseling. They also demonstrate the power of ML algorithms in extracting useful insights from limited data sets.

Racial and Socioeconomic Disparities in Patients With Meningioma: A Retrospective Cohort Study

BACKGROUND

Meningiomas are the most common intracranial neoplasms. Although genomic analysis has helped elucidate differences in survival, there is evidence that racial disparities may influence outcomes. African Americans have a higher incidence of meningiomas and poorer survival outcomes. The etiology of these disparities remains unclear, but may include a combination of pathophysiology and other factors.

OBJECTIVE

To determine factors that contribute to different clinical outcomes in racial populations.

METHODS

We retrospectively reviewed 305 patients who underwent resection for meningiomas at a single tertiary care facility. We used descriptive statistics and univariate, multivariable, and Kaplan-Meier analyses to study clinical, radiographical, and histopathological differences.

RESULTS

Minority patients were more likely to present through the emergency department than an outpatient clinic (P < .0001). They were more likely to present with more advanced clinical symptoms with lower Karnofsky Performance scores, more frequently had peritumoral edema (P = .0031), and experienced longer postoperative stays in the hospital (P = .0053), and African-American patients had higher hospitalization costs (P = .046) and were more likely to be publicly insured. Extent of resection was an independent predictor of recurrence freedom (P = .039). Presentation in clinic setting trended toward an association with recurrence-free survival (P = .055). We observed no significant difference in gross total resection rates, postoperative recurrence, or recurrence-free survival.

CONCLUSION

Minority patients are more likely to present with severe symptoms, require longer perioperative hospitalization, and generate higher hospitalization costs. This may be due to socioeconomic factors that affect access to health care. Targeting barriers to access, especially to subspecialty care, may facilitate more appropriate and timely diagnosis, thereby improving patient care and outcomes.

Absent pyramidal eminence and stapedial tendon associated with congenital stapes footplate fixation: Intraoperative and radiographic findings

OBJECTIVE

Report an association between congenital stapes footplate fixation (CSFF) and radiological absence of the pyramidal eminence and stapedial tendon.

PATIENTS

Children and adults with intraoperatively confirmed CSFF and an absent stapedial tendon.

INTERVENTIONS

Computed tomography (CT); exploratory tympanotomy with stapedotomy.

MAIN OUTCOME MEASURES

Absence of a pyramidal eminence and stapedial tendon aperture identified on preoperative CT that was confirmed intraoperatively.

RESULTS

Eight patients with intraoperative confirmation of CSFF and absent stapedial tendon were retrospectively identified. The average preoperative bone conduction and air conduction pure tone averages were 19.6 dB (SD 15.6 dB) and 55.9 dB (SD 23.6 dB), respectively. The average air-bone gap was 36.3 dB (SD 17.9 dB) preoperatively. In the seven patients who underwent preoperative CT, all were consistently identified to have an absent or hypoplastic pyramidal eminence and absent stapedial tendon aperture at the pyramidal eminence. In six cases, the stapedial footplate appeared normal, while in one case the footplate appeared abnormal which correlated with severe facial nerve prolapse observed intraoperatively. All eight cases underwent exploratory tympanotomy and demonstrated intraoperative stapes footplate fixation, absent stapedial tendon and either absent or hypoplastic pyramidal eminence, which correlated with preoperative CT findings.

CONCLUSIONS

This study identifies a clinically pragmatic association between an absent pyramidal eminence identified on high-resolution CT and the diagnosis of CSFF. In a condition that otherwise generally lacks distinctive radiological features, the absence of a pyramidal eminence on CT in a patient with nonprogressive, congenital conductive hearing loss may strengthen clinical suspicion for CSFF.

Spontaneous Congenital Perilabyrinthine Cerebrospinal Fluid Fistulas

OBJECTIVES

To report a recalcitrant spontaneous cerebrospinal fluid (CSF) fistula arising from multiple, anatomically-linked lateral skull base defects, and to review the available literature to determine optimal techniques for operative repair of congenital CSF fistulae.

METHODS

A patient with recurrent episodes of otologic meningitis was found to have a patent tympanomeningeal fissure, also known as a Hyrtl's fissure, and internal auditory canal (IAC) diverticulum that communicated with the jugular bulb. A systematic review of the literature characterized all reports of spontaneous congenital perilabyrinthine CSF leaks, and all cases of Hyrtl's fissures.

RESULTS

An 11-year-old female was referred for recurrent meningitis. Imaging demonstrated a fistulous connection between the middle ear and IAC diverticulum via the jugular foramen. Specifically, a Hyrtl's fissure was identified, as well as demineralized bone around the jugular bulb. Obliteration of the fissure was initially performed, and a fistula reformed 4 months later. Multifocal CSF egress in the hypotympanum was identified on re-exploration, and middle ear obliteration with external auditory canal (EAC) overclosure was performed. A systematic review of the literature demonstrated 19 cases of spontaneous congenital perilabyrinthine CSF leaks. In total, 6 cases had multiple sources of CSF leak and 2 had history suggestive of intracranial hypertension. All of these noted cases demonstrated leak recurrence. Middle ear obliteration with EAC overclosure was successful in 4 recalcitrant cases.

CONCLUSIONS

Repair of spontaneous congenital perilabyrinthine CSF leaks in cases demonstrating multiple sources of egress or signs of intracranial hypertension should be approached with caution. Middle ear obliteration with EAC overclosure may provide the most definitive management option for these patients, particularly if initial attempt at primary repair is unsuccessful.

Usefulness of Exam Questions and Vital Signs for Predicting the Outcome of Objective Vestibular Tests

OBJECTIVES/HYPOTHESIS

To determine the value of standard clinic screening questions and vital signs in predicting abnormal vestibular function, indicated by standard objective diagnostic tests.

STUDY DESIGN

Retrospective records review.

METHODS

We reviewed electronic medical records of 150 patients seen by the neurotologists or the physician assistant they supervised, in an out-patient tertiary care clinic, between June 2018 and March 2020, and subsequently referred for the complete objective vestibular test battery (VB).

RESULTS

Of standard questions asked during the initial exam about vertigo, disequilibrium, lightheadedness and oscillopsia, only vertigo predicted an abnormal response on the VB. More males than females had abnormal VB responses, P < .05. Pulse was not related to VB score. Significantly more subjects with blood pressure in the range for stage 2 hypertension (blood pressure [BP] stage 2) had abnormal than normal results on the VB, P < .00001. Subjects with BP stage 2 had high rates of diabetes (34.2%) and hypertension (68.4%) as diagnosed by their primary care physicians or cardiologists.

CONCLUSION

Complaints of subjective vertigo and BP in the range of hypertension stage 2 are most likely to predict abnormal findings on the VB. Therefore, during an examination of a patient who comes in complaining of dizziness, two measures may be the most useful for screening: BP in the range of hypertension type 2, when BP is taken by a nurse, and a question to determine whether or not the patient has true vertigo.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:1382-1385, 2021.

Otosclerosis in an Urban Population

OBJECTIVE

To investigate the evolving prevalence of otosclerosis in a large urban population.

METHODS

A retrospective review of patients in a large, urban, public health system was conducted from January 2010 to August 2019 to identify subjects with otosclerosis. Diagnostic testing included audiometry and computed tomography scans. Sex, age at diagnosis, treatment received, race, ethnicity, and country of birth were analyzed for each subject and compared with all eligible patients in the reference population.

RESULTS

A total of 134 patients from a reference population of 672,839 were diagnosed with otosclerosis and analyzed. The otosclerosis patients were predominantly Hispanic (73%), of which the majority were foreign born (87%). The average age at onset was 46 years and 59% were women. The overall prevalence of otosclerosis was 20 of 100,000 patients. The crude prevalence of otosclerosis by ethnicity was 43 of 100,000 for Hispanics, 12.6 of 100,000 for Caucasians, and 3 of 100,000 for African Americans. Within the Hispanic population, the prevalence of otosclerosis was 60 of 100,000 for foreign-born individuals and 16 of 100,000 for those born in the USA (odds ratio [OR] = 3.69, [95% confidence interval [CI], 2.02-6.76], p < 0.0001). Prevalence was not significantly different among Caucasians and US-born Hispanics.

CONCLUSION

Otosclerosis in the studied population was most common among Hispanic patients, though it was strongly influenced by country of birth. The "imported" otosclerosis cases are best explained by environmental influence rather than ethnic susceptibility. This discrepancy is likely due to variance in measles immunization rates among North and Central American countries before 1990.

Prevalence of and Associations With Distress and Professional Burnout Among Otolaryngologists: Part I, Trainees

OBJECTIVE

To assess the prevalence of distress and burnout in otolaryngology trainees, including associations with relevant sociodemographic and professional factors, and to compare these results with those of attending otolaryngologists.

STUDY DESIGN

A cross-sectional survey of trainees and attending physicians.

SETTING

Twelve academic otolaryngology programs.

METHODS

Distress and burnout were measured with the Expanded Physician Well-being Index and the 2-item Maslach Burnout Inventory. The Patient Health Questionnaire-2 and Generalized Anxiety Disorder-2 were used to screen for depressive disorders and anxiety disorders, respectively. Associations with sociodemographic and professional characteristics were assessed.

RESULTS

Of the 613 surveys administered to trainees and attending physicians, 340 were completed (56%). Among 154 trainees, distress was present in 49%, professional burnout in 35%, positive depressive disorder screening in 5%, and positive anxiety disorder screening in 16%. In univariable analysis, female gender, hours worked in a typical week (HW), and nights on call in a typical week (NOC) were significantly associated with distress. In multivariable analysis, female gender (odds ratio, 3.91; P = .001) and HW (odds ratio for each 10 HW, 1.89; P = .003) remained significantly associated with distress. Female gender, HW, and NOC were significantly associated with burnout univariably, although only HW (odds ratio for each 10 HW, 1.92; P = .003) remained significantly associated with burnout in a multivariable setting. Attending physicians had less distress than trainees (P = .02) and felt less callous and less emotionally hardened than trainees (P < .001).

CONCLUSION

Otolaryngology trainees experience significant work-place distress (49%) and burnout (35%). Gender, HW, and NOC had the strongest associations with distress and burnout.

Prevalence of and Associations With Distress and Professional Burnout Among Otolaryngologists: Part II, Attending Physicians

OBJECTIVE

To ascertain the prevalence of and associations with distress and professional burnout among academic otolaryngology attending physicians.

STUDY DESIGN

Cross-sectional survey.

SETTING

Twelve US academic otolaryngology programs.

METHODS

A questionnaire was administered that encompassed sociodemographic and professional features, the Expanded Physician Well-being Index for distress, the 2-item Maslach Burnout Inventory for professional burnout, the Patient Health Questionnaire-2 screen for major depressive disorder, and the Generalized Anxiety Disorder-2 screen for generalized anxiety disorder.

RESULTS

The survey response rate was 56% and included 186 attending physicians. The average respondent age was 47 years; 72% were men; 93% were married or partnered; and 86% had children. Distress was present in 40%, professional burnout in 26%, positive depression screening in 8%, and positive anxiety screening in 11%. In a univariable setting, age, hours worked in a typical week, nights on call in a typical week, and years of practice were significantly associated with distress, although in a multivariable setting, only hours worked in a typical week remained significantly associated with a positive Expanded Physician Well-being Index screen (odds ratio for each 10-hour increase, 2.61; 95% CI, 1.73-3.93; P < .001). In a univariable setting, hours worked in a typical week was significantly associated with a positive Maslach Burnout Inventory screen.

CONCLUSION

Distress or professional burnout occurs in more than a quarter of academic otolaryngology attending physicians, whereas the prevalence of depression or anxiety is approximately 10%. The number of hours worked per week had the strongest association with distress and burnout. These findings may be used to develop and implement programs to promote physician well-being and mitigate professional burnout.

Cochlear implantation after traumatic brain injury without otic capsule fracture: A case report and literature review

OBJECTIVE

The aim of this study was to report a case of cochlear implantation (CI) for a patient with an otic capsule-sparing traumatic brain injury (TBI) and to review the relevant literature.

METHODS

A patient with history of TBI received a CI for bilateral profound hearing loss. A systematic review of the literature was performed to identify and compare similar cases.

RESULTS

A 36-year-old male with a history of hearing loss from right acute labyrinthitis was referred for bilateral profound sensorineural hearing loss (SNHL) after a fall with associated injury to the central auditory nervous system (CANS) including the brainstem. On the right, behavioral acoustic threshold measurements were in the profound range with absent OAEs. On the left, testing revealed no measurable behavioral acoustic thresholds and variable physiologic measures. A right unilateral cochlear implant was performed with most recent follow-up demonstrating speech awareness thresholds of 25 dB HL with excellent detection of all 6 Ling sounds. However, the patient also continues to suffer from other neurologic sequelae related to his TBI, which challenge his ability to demonstrate objective and subjective benefit. A systematic review of the literature demonstrates variable outcomes for patients with TBI and SNHL.

CONCLUSIONS

Patients with profound SNHL and TBI present a distinct rehabilitative challenge for clinicians. CI may provide meaningful benefit in this population, though care should be taken in patient selection and counseling.

The Role of Merlin/NF2 Loss in Meningioma Biology

Mutations in the neurofibromin 2 (NF2) gene were among the first genetic alterations implicated in meningioma tumorigenesis, based on analysis of neurofibromatosis type 2 (NF2) patients who not only develop vestibular schwannomas but later have a high incidence of meningiomas. The NF2 gene product, merlin, is a tumor suppressor that is thought to link the actin cytoskeleton with plasma membrane proteins and mediate contact-dependent inhibition of proliferation. However, the early recognition of the crucial role of NF2 mutations in the pathogenesis of the majority of meningiomas has not yet translated into useful clinical insights, due to the complexity of merlin’s many interacting partners and signaling pathways. Next-generation sequencing studies and increasingly sophisticated NF2-deletion-based in vitro and in vivo models have helped elucidate the consequences of merlin loss in meningioma pathogenesis. In this review, we seek to summarize recent findings and provide future directions toward potential therapeutics for this tumor.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on Hearing Preservation Outcomes in Patients With Sporadic Vestibular Schwannomas

Question 1

What is the overall probability of maintaining serviceable hearing following stereotactic radiosurgery utilizing modern dose planning, at 2, 5, and 10 yr following treatment?

Recommendation

Level 3: Individuals who meet these criteria and are considering stereotactic radiosurgery should be counseled that there is moderately high probability (>50%-75%) of hearing preservation at 2 yr, moderately high probability (>50%-75%) of hearing preservation at 5 yr, and moderately low probability (>25%-50%) of hearing preservation at 10 yr.

Question 2

Among patients with AAO-HNS (American Academy of Otolaryngology-Head and Neck Surgery hearing classification) class A or GR (Gardner-Robertson hearing classification) grade I hearing at baseline, what is the overall probability of maintaining serviceable hearing following stereotactic radiosurgery, utilizing modern dose planning, at 2, 5, and 10 yr following treatment?

Recommendation

Level 3: Individuals who meet these criteria and are considering stereotactic radiosurgery should be counseled that there is a high probability (>75%-100%) of hearing preservation at 2 yr, moderately high probability (>50%-75%) of hearing preservation at 5 yr, and moderately low probability (>25%-50%) of hearing preservation at 10 yr.

Question 3

What patient- and tumor-related factors influence progression to nonserviceable hearing following stereotactic radiosurgery using ≤13 Gy to the tumor margin?

Recommendation

Level 3: Individuals who meet these criteria and are considering stereotactic radiosurgery should be counseled regarding the probability of successful hearing preservation based on the following prognostic data: the most consistent prognostic features associated with maintenance of serviceable hearing are good preoperative word recognition and/or pure tone thresholds with variable cut-points reported, smaller tumor size, marginal tumor dose ≤12 Gy, and cochlear dose ≤4 Gy. Age and sex are not strong predictors of hearing preservation outcome.

Question 4

What is the overall probability of maintaining serviceable hearing following microsurgical resection of small to medium-sized sporadic vestibular schwannomas early after surgery, at 2, 5, and 10 yr following treatment?

Recommendation

Level 3: Individuals who meet these criteria and are considering microsurgical resection should be counseled that there is a moderately low probability (>25%-50%) of hearing preservation immediately following surgery, moderately low probability (>25%-50%) of hearing preservation at 2 yr, moderately low probability (>25%-50%) of hearing preservation at 5 yr, and moderately low probability (>25%-50%) of hearing preservation at 10 yr.

Question 5

Among patients with AAO-HNS class A or GR grade I hearing at baseline, what is the overall probability of maintaining serviceable hearing following microsurgical resection of small to medium-sized sporadic vestibular schwannomas early after surgery, at 2, 5, and 10 yr following treatment?

Recommendation

Level 3: Individuals who meet these criteria and are considering microsurgical resection should be counseled that there is a moderately high probability (>50%-75%) of hearing preservation immediately following surgery, moderately high probability (>50%-75%) of hearing preservation at 2 yr, moderately high probability (>50%-75%) of hearing preservation at 5 yr, and moderately low probability (>25%-50%) of hearing preservation at 10 yr.

Question 6

What patient- and tumor-related factors influence progression to nonserviceable hearing following microsurgical resection of small to medium-sized sporadic vestibular schwannomas?

Recommendation

Level 3: Individuals who meet these criteria and are considering microsurgical resection should be counseled regarding the probability of successful hearing preservation based on the following prognostic data: the most consistent prognostic features associated with maintenance of serviceable hearing are good preoperative word recognition and/or pure tone thresholds with variable cut-points reported, smaller tumor size commonly less than 1 cm, and presence of a distal internal auditory canal cerebrospinal fluid fundal cap. Age and sex are not strong predictors of hearing preservation outcome.

Question 7

What is the overall probability of maintaining serviceable hearing with conservative observation of vestibular schwannomas at 2, 5, and 10 yr following diagnosis?

Recommendation

Level 3: Individuals who meet these criteria and are considering observation should be counseled that there is a high probability (>75%-100%) of hearing preservation at 2 yr, moderately high probability (>50%-75%) of hearing preservation at 5 yr, and moderately low probability (>25%-50%) of hearing preservation at 10 yr.

Question 8

Among patients with AAO-HNS class A or GR grade I hearing at baseline, what is the overall probability of maintaining serviceable hearing with conservative observation at 2 and 5 yr following diagnosis?

Recommendation

Level 3: Individuals who meet these criteria and are considering stereotactic radiosurgery should be counseled that there is a high probability (>75%-100%) of hearing preservation at 2 yr, and moderately high probability (>50%-75%) of hearing preservation at 5 yr. Insufficient data were available to determine the probability of hearing preservation at 10 yr for this population subset.

Question 9

What patient and tumor-related factors influence progression to nonserviceable hearing during conservative observation?

Recommendation

Level 3: Individuals who meet these criteria and are considering observation should be counseled regarding probability of successful hearing preservation based on the following prognostic data: the most consistent prognostic features associated with maintenance of serviceable hearing are good preoperative word recognition and/or pure tone thresholds with variable cut-points reported, as well as nongrowth of the tumor. Tumor size at the time of diagnosis, age, and sex do not predict future development of nonserviceable hearing during observation.  The full guideline can be found at: https://www.cns.org/guidelines/guidelines-manage-ment-patients-vestibular-schwannoma/chapter_3.

Bone Conduction Implants for Hearing Rehabilitation in Skull Base Tumor Patients

Bone conduction implants transfer sound to the inner ear through direct vibration of the skull. In patients with skull base tumors and infections, these devices can bypass a dysfunctional ear canal and/or middle ear. Though not all skull base surgery patients opt for bone conduction hearing rehabilitation, a variety of these devices have been developed and marketed over time. This article reviews the evolution and existing state of bone conduction technology.

Spontaneous resolution of a petrous apex cholesterol granuloma

Cholesterol granuloma is the most common primary lesion of the petrous apex. Management of petrous apex cholesterol granuloma has evolved in recent years from primary surgical treatment to conservative observation. In this article, a case of spontaneous resolution of a petrous apex cholesterol granuloma is described. To the authors' knowledge, this is the first known report of spontaneous involution of a petrous apex cholesterol granuloma. Radiographic differential diagnosis of petrous apex lesions and the natural history of cholesterol granulomas are discussed.

Detection of modiolar proximity through bipolar impedance measurements

OBJECTIVES

To test the hypothesis that bipolar electrical impedance measurements in perimodiolar cochlear implants (CIs) may be used to differentiate between perimodiolar insertion technique favoring proximity to the modiolus or lateral wall.

STUDY DESIGN AND METHODS

Bipolar impedances are a measure of electrical resistance between pairs of electrode contacts in a CI. Stimulation is through biphasic pulses at fixed frequency. Impedance measurements were made in real time through sequential sampling of electrode pairs. Perimodiolar electrodes were inserted in temporal bones using one of two techniques: 1) In the standard insertion technique (SIT), the electrode array slides along the lateral wall during insertion. 2) In the Advance Off Stylet (Cochlear Ltd. Sydney) technique (AOS), the electrode maintains modiolar contact throughout the insertion process. A set of 22 insertions were performed in temporal bone specimens using perimodiolar electrode arrays with both AOS and SIT. Buffered saline was used as a substitute for natural perilymph based on similar electrical conductivity properties. Impedance with and without stylet removal were recorded with a 30-second sampling window at final insertion depth.

RESULTS

There is a significant difference in bipolar impedance measures between AOS and SIT, with impedances rising in measurements with stylet removal. Evaluation was based on two-sided analysis of variance considering technique and electrode with P < 0.025.

CONCLUSION

Bipolar electrical impedance can be used to detect relative motion toward the modiolus inside the cochlea. This detection method has the potential to optimize intraoperative placement of perimodiolar electrode arrays during implantation. We anticipate that this will result in lower excitation thresholds and improved hearing outcome.

LEVEL OF EVIDENCE

NA. Laryngoscope, 127:1413-1419, 2017.

Initial radiographic tumor control is similar following single or multi-fractionated stereotactic radiosurgery for jugular paragangliomas

OBJECTIVE

To evaluate radiographic tumor control and treatment-related toxicity in glomus jugulare tumors treated with stereotactic radiosurgery (SRS).

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary academic referral center.

PATIENTS

Glomus jugulare tumors treated with SRS between 1998 and 2014 were identified. The data analysis only included patients with at least 18months of post-treatment follow up (FU).

INTERVENTION

Patients were treated with either single fraction or fractionated SRS.

MAIN OUTCOME MEASURE

Patient demographics and tumor characteristics were assessed. Radiographic control was determined by comparing pre and post treatment MRI, and was categorized as no change, regression, or progression.

RESULTS

Eighteen patients were treated with SRS, and 14 met inclusion criteria. Median age at treatment was 55years (range 35-79), and 71.4% of patients were female. 5 patients (35.7%) received single fraction SRS (dose range 15-18Gy), and 9 (64.3%) fractionated therapy (dose 3-7Gy×3-15 fractions). Median tumor volume was 3.78cm(3) (range 1.15-30.6). Median FU was 28.8months (range 18.6-56.1), with a mean of 31.7months. At their last recorded MRI, 7 patients (50%) had tumor stability, 6 (42.9%) had improvement, and 1 (7.1%) had progression. Disease improvement and progression rates in the single fraction group were 40% and 0%, and in the multiple-fraction group, 44.4% and 11.1%, respectively. There was no statistically significant difference in disease improvement (p=0.88) or progression (p=0.48) rates between groups (unpaired t-test).

CONCLUSIONS

At a median follow up of 28months, both single fraction and fractionated SRS appear to have comparable radiographic tumor control outcomes and toxicity profiles.

Cholesterol Granuloma Development following Temporal Bone Surgery

OBJECTIVE

To describe the clinical presentation and management of patients with cholesterol granulomas (CGs) that develop following temporal bone surgery.

STUDY DESIGN

Case series with chart review.

SETTING

Two independent tertiary academic referral centers.

SUBJECTS AND METHODS

A multicenter retrospective review was performed to identify all patients between 2001 and 2014 who were diagnosed with a CG that developed following temporal bone surgery. Patients with a history of idiopathic petrous apex CGs were excluded, as were those with <6 months of follow-up after diagnosis. Demographic and clinical data were recorded at presentation, and the main outcome measure was symptom evolution over time.

RESULTS

A total of 20 patients met inclusion criteria (median age, 55.0 years; 70.0% female), and their cases were analyzed. Diagnosis was made, on average, 149.5 months (median, 94.5; range, 13.0-480.0) following a temporal bone operation, which was for chronic ear disease in 75.0% of cases. The most common presenting symptoms were otalgia (55.0%) and otorrhea (40.0%). In patients initially managed with observation, 71.4% required no surgical intervention through a mean of 56.8 months (median, 30; range, 12.0-178.0) of follow-up. For those who initially underwent surgical excision, durable symptom relief was achieved in 66.7% of cases.

CONCLUSION

Postoperative CG formation in the temporal bone is a rare occurrence that can be encountered years following surgery. The present study suggests that conservative management can be appropriate for many cases in which patients are relatively asymptomatic.

Pediatric Endoscopic Cholesteatoma Surgery

Objectives

(1) To describe and review a single center’s pediatric endoscopic cholesteatoma experience, including surgical and audiologic outcomes. (2) To assess the most common locations of residual cholesteatoma following endoscopic removal.

Study Design

Case series with chart review.

Setting

Tertiary otologic referral center.

Subjects

Patients <19 years of age who underwent cholesteatoma removal with either endoscopic or microscopic visualization.

Methods

In a comparison of patients who underwent total endoscopic ear surgery (TEES), combined endoscopic-microscopic surgery, or microscopic surgery, analyzed outcomes included locations and incidence of recurrent and residual cholesteatoma, complications, and audiometric testing.

Results

Sixty-six patients (mean age, 10.9 years; range, 4-18 years; 43.4% female) with 76 ears met inclusion criteria. The average overall follow-up was 18.8 months (range, 6.7-48.3). Forty-seven (61.8%) ears underwent microscopic removal of cholesteatoma; 29 (38.1%) ears underwent combined endoscopic-microscopic removal; and 8 (10.5%) ears underwent TEES removal. Significantly more mastoidectomies were completed in microscopic cases as compared with endoscopic cases ( P = .049). Though second-look procedures occurred in 15 (51.7%) endoscopic cases and 10 (21.3%) microscopic cases ( P = .006), the rate of residual disease was 20.0% and 40.0% in endoscopic and microscopic cases, respectively ( P = .38). When controlling for preoperative hearing, only the air-bone gap for TEES demonstrated significant improvement ( P = .009). No complications were noted.

Conclusion

The present report describes our experience with pediatric endoscopic cholesteatoma surgery, demonstrating similar hearing outcomes, rates of recurrence and residual disease, and complication rates as compared with traditional microscopic techniques.

Durability of Hearing Preservation after Cochlear Implantation with Conventional-Length Electrodes and Scala Tympani Insertion

OBJECTIVES

To analyze factors that influence hearing preservation over time in cochlear implant recipients with conventional-length electrode arrays located entirely within the scala tympani.

STUDY DESIGN

Case series with planned chart review.

SETTING

Single tertiary academic referral center.

SUBJECTS AND METHODS

A retrospective review was performed to analyze a subgroup of cochlear implant recipients with residual acoustic hearing. Patients were included in the study only if their electrode arrays remained fully in the scala tympani after insertion and serviceable acoustic hearing (≤80 dB at 250 Hz) was preserved. Electrode array location was verified through a validated radiographic assessment tool. Patients with <6 months of audiologic follow-up were excluded. The main outcome measure was change in acoustic hearing thresholds from implant activation to the last available follow-up.

RESULTS

A total of 16 cases met inclusion criteria (median age, 70.6 years; range, 29.4-82.2; 50% female). The average follow-up was 18.0 months (median, 16.1; range, 6.2-36.4). Patients with a lateral wall electrode array were more likely to have stable acoustic thresholds over time (P < .05). Positive correlations were seen between continued hearing loss following activation and larger initial postoperative acoustic threshold shifts, though statistical significance was not achieved. Age, sex, and noise exposure had no significant influence on continued hearing preservation over time.

CONCLUSIONS

To control for hearing loss associated with interscalar excursion during cochlear implantation, the present study evaluated patients only with conventional electrode arrays located entirely within the scala tympani. In this group, the style of electrode array may influence residual hearing preservation over time.

Cochlear Implantation in the Setting of Perioperative Anticoagulation and Antiplatelet Therapy

Objective

To describe surgical outcomes and perioperative complications in patients taking antiplatelet and anticoagulation medications while undergoing cochlear implantation.

Study Design

Case series with chart review.

Setting

Two tertiary otologic referral center.

Subjects and Methods

Forty-six adult patients (2005-2014) who underwent cochlear implantation while on perioperative antiplatelet and/or anticoagulation therapy without interruption. Outcomes included estimated intraoperative blood loss, perception of increased difficulty secondary to bleeding, and postoperative complications attributable to continuing anticoagulation or antiplatelet therapy.

Results

The cases of 46 patients (mean age, 69.5 years; 30.2% female) were analyzed. Of these, 39 patients were taking aspirin, 10 warfarin, and 7 clopidogrel. Aside from 3 (6.5%) patients with postoperative bruising without hematoma and 1 patient (2.2%) who reported self-resolving oral cavity blood, no intraoperative or postoperative complications occurred in any patient that could be ascribed to antiplatelet or anticoagulant use.

Conclusion

These data demonstrate that the risk of perioperative complications from continued antiplatelet or anticoagulation therapy is low. For subjects who are at risk of major complications (eg, deep venous thrombosis, pulmonary embolism, myocardial infarction, cerebrovascular accident) from temporary medication cessation, continuing antiplatelet or anticoagulation therapy through the perioperative period is an appropriate strategy.

Impact of Intrascalar Electrode Location, Electrode Type, and Angular Insertion Depth on Residual Hearing in Cochlear Implant Patients: Preliminary Results

OBJECTIVE

To evaluate the relationship between intrascalar electrode location, electrode type (lateral wall, perimodiolar, and midscala), and angular insertion depth on residual hearing in cochlear implant (CI) recipients.

SETTING

Tertiary academic hospital.

PATIENTS

Adult CI patients with functional preoperative residual hearing with preoperative and postoperative CT scans.

INTERVENTION

Audiological assessment after CI.

MAIN OUTCOME MEASURES

Electrode location, angular insertion depth, residual hearing post-CI, and word scores with CI (consonant-nucleus-consonant [CNC]).

RESULTS

Forty-five implants in 36 patients (9 bilateral) were studied. Thirty-eight electrode arrays (84.4%) were fully inserted in scala tympani (ST), 6 (13.3%) crossed from ST to scala vestibuli (SV), and 1 (2.2%) was completely in SV. Twenty-two of the 38 (57.9%) with full ST insertion maintained residual hearing at 1 month compared with 0 of the 7 (0%) with non-full ST insertion (p = 0.005). Three surgical approaches were used: cochleostomy (C) 6/44, extended round window (ERW) 8/44, and round window (RW) 30/44. C and ERW were small group to compare with RW approaches. However if we combine C + ERW, then RW has higher chance of full ST insertion (p = 0.014). Looking at the full ST group, neither age, sex, nor electrode type demonstrated statistically significant associations with hearing preservation (p = 0.646, p = 0.4, and p = 0.929, respectively). The median angular insertion depth was 429° (range, 373°-512°) with no significant difference between the hearing and nonhearing preserved groups (p = 0.287).

CONCLUSION

Scalar excursion is a strong predictor of losing residual hearing. However, neither age, sex, electrode type, nor angular insertion depth was correlated with hearing preservation in the full ST group. Techniques to decrease the risk of electrode excursion from ST are likely to result in improved residual hearing and CI performance.

Facial nerve stimulation associated with cochlear implant use following temporal bone fractures

OBJECTIVE

To describe the incidence and management of patients with facial nerve stimulation (FNS) associated with cochlear implant (CI) use in the setting of a prior temporal bone fracture.

PATIENTS

One adult CI recipient is reported who experienced implant associated FNS with a history of a temporal bone fracture. Additionally, a literature search was performed to identify similar patients from previous descriptions of CI related FNS.

MAIN OUTCOME MEASURES

Presence of FNS after implantation and ability to modify implant programming to avoid FNS.

RESULTS

The patient in the present report experienced FNS for middle and basal electrodes during intraoperative neural response telemetry (NRT) in the absence of any surgical exposure or manipulation of the facial nerve. FNS was absent during device activation, but it recurred during follow-up programming sessions. However, additional programming has prevented further FNS during regular implant use. Four other patients with FNS after temporal bone fracture were identified from the literature, and the present case represents the one of two cases in which reprogramming allowed for implant use without FNS.

CONCLUSIONS

CI associated FNS is uncommon in patients with a history of a temporal bone fracture, but it is likely that fracture lines provide a lower impedance pathway to the adjacent facial nerve and thus reduce the threshold for FNS. The present report suggests that, in the setting of a prior temporal bone fracture, NRT is not always a reliable predictor of FNS during implant use, and programming changes can help to mitigate FNS when it occurs.

Cochlear implantation: a biomechanical prosthesis for hearing loss

Cochlear implants are a medical prosthesis used to treat sensorineural deafness, and one of the greatest advances in modern medicine. The following article is an overview of cochlear implant technology. The history of cochlear implantation and the development of modern implant technology will be discussed, as well as current surgical techniques. Research regarding expansion of candidacy, hearing preservation cochlear implantation, and implantation for unilateral deafness are described. Lastly, innovative technology is discussed, including the hybrid cochlear implant and the totally implantable cochlear implant.

228 Cases of Cochlear Implant Receiver-Stimulator Placement in a Tight Subperiosteal Pocket without Fixation

Objectives

(1) To investigate the outcomes of cochlear implant receiver-stimulator (RS) placement using a tight subperiosteal pocket technique without device fixation and (2) to compare the efficiency of this approach with the traditional bony well and trough technique.

Study Design

Case series with planned chart review.

Setting

Single tertiary academic referral center.

Subjects and Methods

All cochlear implant surgeries utilizing a tight subperiosteal pocket without additional fixation or use of a bone well were identified retrospectively. Revision cases were only included if the tight subperiosteal pocket technique was used during the initial surgery. Patients with less than 6 months of postoperative follow-up were excluded. Primary outcome measures included RS migration, flap complications, device failure, and percentage reduction in operative time.

Results

Two hundred twenty-eight cases (average age 45.3 years) met inclusion criterion and were analyzed. At a mean follow-up of 18.1 months, no patient experienced RS migration. One patient experienced a postoperative hematoma that was managed with observation. One patient developed a surgical site infection that resolved following exploration and intravenous antibiotics. The subperiosteal pocket technique resulted in an 18.9% reduction in total operative time compared to a more conventional RS placement method ( P < .01).

Conclusions

The tight subperiosteal pocket without fixation is a safe, durable, and time-saving technique for RS placement during cochlear implantation. Notably, device migration and flap complications are very uncommon.

Glomus tympanicum: a review of 115 cases over 4 decades

OBJECTIVE

To characterize the clinical presentation, surgical management, and outcomes of a large consecutive cohort of patients with glomus tympanicum (GT) tumors managed at a single tertiary referral group over 4 decades.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary neurotological referral center.

SUBJECTS AND METHODS

All patients underwent surgical treatment of histopathologically confirmed GT between January 1973 and March 2014. Audiometric outcomes were reported according to AAO-HNS guidelines, and tumor stage was described using the Glasscock-Jackson classification system.

RESULTS

There were 115 patients (90.4% women; mean age, 55.2 years) who met the inclusion criteria; 38 (33.0%) cases of GT were stage I, 51 (44.3%) stage II, 10 (8.7%) stage III, and 16 (13.9%) stage IV. There were 108 (93.9%) patients who underwent gross total removal, while 7 (6.1%) received less than complete resection for advanced disease that was adherent to the petrous carotid artery, facial nerve, stapes footplate, or round window. Two patients who underwent gross total resection experienced transient facial paresis, and 1 had internal carotid injury with stroke. No patients had been diagnosed with recurrent disease at a mean follow-up of 30.4 months.

CONCLUSION

Surgery remains the treatment of choice for GT, providing a high rate of tumor control and resolution of aural symptoms with a low risk of complications. The surgical approach and extent of resection should be tailored to the patient. Gross total resection can be performed in over 90% of patients; however, leaving a limited adherent tumor remnant on the facial nerve or carotid artery should be considered with advanced infiltrative disease to prevent unnecessary morbidity.

Natural History of Glomus Jugulare

Objective

To characterize clinical disease progression and radiologic growth in a series of observed, previously untreated, glomus jugulare tumors (GJT).

Study Design

Retrospective review.

Setting

Tertiary neurotologic referral center.

Subjects and Methods

All patients with primary GJTs that were observed without intervention for a minimum of 2 years. Primary outcome measures included progression of cranial neuropathy and/or radiologic growth.

Results

A total of 15 patients (80% female; median age, 69.6 years) with 16 GJTs met inclusion criteria. The most common indications for observation included advanced age (11; 73%) and patient preference (11; 73%). Cranial nerve function remained stable in most subjects over a median clinical follow-up period of 86.4 months. Among the 12 with serial imaging, 5 (42%) GJTs demonstrated radiologic growth, while 7 (58%) remained stable. The median growth rate of the 5 enlarging tumors using the maximum linear dimension was 0.8 mm/y (range, 0.6-1.6 mm/y) or 0.4 cm3/y (0.1-0.9 cm3/y) using volumetric analysis. There were no deaths attributable to tumor progression or treatment.

Conclusion

In an older subset of patients, we found that a significant number of GJTs do not grow after time of diagnosis and symptoms frequently remain stable for many years. Even with disease progression, most GJTs exhibit indolent growth with slowly progressive cranial neuropathy, affording satisfactory physiologic compensation in most patients. In the absence of brainstem compression or concern for malignancy, observation of GJTs is a viable initial management option for elderly patients.

Subtotal Resection for Management of Large Jugular Paragangliomas with Functional Lower Cranial Nerves

Objectives

To evaluate tumor control following subtotal resection of advanced jugular paragangliomas in patients with functional lower cranial nerves and to investigate the utility of salvage radiotherapy for residual progressive disease.

Study Design

Case series with planned chart review.

Setting

Tertiary academic referral center.

Subjects and Methods

Patients who presented with advanced jugular paragangliomas and functional lower cranial nerves were analyzed. Primary outcome measures included extent of resection, long-term tumor control, need for additional treatment, and postoperative lower cranial nerve function.

Results

Twelve patients (mean age, 46.2 years; 7 women, 58.3%) who met inclusion criteria were evaluated between 1999 and 2013. The mean postoperative residual tumor volume was 27.7% (range, 3.5%-75.0%) of the preoperative volume. When the residual tumor volume was less than 20% of the preoperative volume, no tumor growth occurred over an average of 44.6 months of follow-up ( P < .01). Four tumors (33.3%) demonstrated serial growth at a mean of 23.5 months following resection, 2 of which were treated with salvage stereotactic radiotherapy providing control through the last recorded follow-up. No patient experienced permanent postoperative lower cranial neuropathy as a result of surgery.

Conclusion

Subtotal resection of jugular paragangliomas with preservation of the lower cranial nerves is a viable management strategy. If more than 80% of the preoperative tumor volume is resected, the residual tumor seems less likely to grow.

Natural History of Jugular Paragangliomas: A Review of 16 Patients Managed with Conservative Observation

Objectives:

Characterize radiologic growth and clinical disease progression in a cohort of observed, previously untreated, jugular paraganglioma tumors (JPT).

Methods:

Retrospective review evaluating all patients with primary JPTs that were observed with serial clinical examination and imaging between 1993 and 2013. Primary outcome measures included radiographic growth and progression of cranial neuropathy.

Results:

A total of 16 patients (75% female, median age 65.2 years) met inclusion criteria. One JPT was stage I, 7 stage II, 7 stage III, and 1 stage IV. Primary indications for observation included advanced age, minimal symptoms, contralateral paraganglioma(s), and patient preference. The most common presenting symptoms were hearing loss and pulsatile tinnitus; 6 patients were found to have lower cranial neuropathy at time of diagnosis (2 CN 9, 6 CN 10, 2 CN 11, 1 CN 12). At a mean clinical follow-up of 67 months, 6 patients endured progressive cranial nerve deficits and 4 tumors demonstrated unequivocal growth; the average rate of tumor growth was 1.2 mm/year. Six patients underwent vocal cord medialization procedures for dysphonia. Notably, no patients required feeding tube placement or tracheostomy and there were no deaths attributable to tumor progression.

Conclusions:

In the absence of brainstem compression or concern of malignancy, initial observation of JPTs should be considered. A significant number of tumors do not grow after time of diagnosis, and symptoms frequently remain stable for many years. Even with disease progression, most JPTs exhibit indolent growth with slowly progressive cranial neuropathy affording satisfactory physiologic compensation in most patients.

Tight Subperiosteal Pocket during Cochlear Implant Surgery: Results in a Large Cohort of Patients

Objectives:

(1) Investigate the results of cochlear implant receiver-stimulator (RS) placement using the tight postauricular subperiosteal pocket technique. (2) Compare the efficiency of solely using a tight subperiosteal pocket compared to the conventional bone-recess technique.

Methods:

Retrospective series from a tertiary academic referral center. All primary and revision cochlear implant patients in whom the RS was placed into a tight subperiosteal pocket without additional fixation were included. Primary outcome measures included RS migration, prevalence of flap complications requiring revision surgery, and time difference comparing the conventional bony well and trough technique to use of a tight subperiosteal pocket.

Results:

Two hundred consecutive cochlear implants (average age 46.9 years) were analyzed. At a mean follow-up of 12.8 months, only 1 patient experienced device migration; however, none have required revision to date for complications related to RS placement. One patient experienced a hematoma that was managed with observation, and no other soft-tissue flap complications occurred. The subperiosteal pocket technique resulted in a 20% reduction in total operative time compared to conventional RS placement methods ( P < .01).

Conclusions:

The tight subperiosteal pocket is a safe, durable, and time saving technique for RS placement during cochlear implantation. Notably, the prevalence of device migration was exceedingly low, and none have required revision surgery for device drift or flap complications to date.

Subtotal Resection for Management of Large Jugular Paragangliomas with Intact Lower Cranial Nerves

Objectives:

(1) Evaluate the use of subtotal resection as the primary treatment modality for large jugular paragangliomas in patients with intact lower cranial nerves. (2) Evaluate functional outcomes and tumor control following subtotal resection. (3) Identify the utility of salvage radiotherapy for residual progressive disease.

Methods:

Retrospective series from a tertiary academic referral center evaluating patients who presented with advanced (Glasscock-Jackson grade 3 to 4) jugular paragangliomas (JP) and normal lower cranial nerve function. Primary outcome measures included extent of resection, long-term tumor control, need for additional treatment, and postoperative lower cranial nerve function.

Results:

Fourteen patients seen between 1999 and 2013 (mean age 48.6 years; range, 26-70) met inclusion criteria. The average maximum preoperative tumor dimension was 3.1 cm. The mean postoperative residual tumor volume was 29.3% (range, 3.5%-58.4%). When the residual tumor volume was less than 20% of the preoperative volume, no tumor growth occurred through an average of 35.4 months of follow-up ( P < .01). Four tumors (28.6%) demonstrated serial growth at an average of 22.5 months following resection, 3 of which were treated with salvage stereotactic radiotherapy providing durable control at an average of 12 months of follow-up. No patient experienced permanent postoperative lower cranial neuropathy.

Conclusions:

Subtotal resection of JP with preservation of the lower cranial nerves is a viable management strategy. If >80% of the preoperative tumor volume is resected, the residual tumor is less likely to grow. Radiotherapy offers effective treatment for recurrent tumor following subtotal resection.

Evolution in Surgical Management of Glomus Tympanicum over 40 Years: A Review of 114 Cases

Objectives:

Report surgical management and outcomes among a large cohort of patients with glomus tympanicum (GT) managed by a single tertiary referral group over 4 decades.

Methods:

Retrospective chart review evaluating all patients that underwent surgical treatment of histopathologically confirmed GT between 1973 and 2013. Pre- and postoperative audiometric outcomes were reported according to American Academy of Otolaryngology—Head and Neck Surgery reporting guidelines and tumor stage was described using the Glasscock-Jackson classification system.

Results:

A total of 114 patients (90.2% female, mean age 54.0 years) met inclusion criteria. Eleven cases were referred following recurrence, while the remaining 103 patients were treated primarily; 38 (33.3%) GTs were stage I, 52 (45.6%) stage II, 9 (7.9%) stage III, and 15 (13.2%) stage IV. A total of 105 (92.1%) patients underwent gross total removal, while 9 (7.9%) received subtotal resection for advanced disease adherent to the carotid artery and/or facial nerve. Two patients who underwent gross total resection experienced transient facial paresis and one suffered internal carotid injury with stroke. No patients have recurred at a mean follow-up of 39 months.

Conclusions:

Surgical approach and extent of resection should be tailored to the patient. Gross total resection can be obtained in over 90% of patients, however leaving adherent tumor remnant on the facial nerve or carotid artery should be considered in patients with advanced infiltrative disease in order to prevent unnecessary morbidity. Microsurgical resection remains the treatment of choice for GT providing a high rate of tumor control and improvement in audiologic symptoms.

The Impact of Perioperative Oral Steroid Use on Low-Frequency Hearing Preservation after Cochlear Implantation

Objectives:

(1) Investigate factors that impact low frequency hearing preservation following cochlear implantation. (2) Evaluate the efficacy of a perioperative oral steroid taper in this setting.

Methods:

Retrospective series from a single surgeon at a tertiary academic referral center. Patients were candidates for a hearing preservation protocol based on their preoperative pure tone thresholds. The tympanic space was bathed in steroids prior to opening the round window membrane in all cases, and all patients were implanted using electrodes designed for atraumatic insertion. One group of patients received a 2-week oral prednisone taper beginning 3 days prior to surgery. The primary outcome measure was the preservation of low frequency pure tone hearing on a 1-month postoperative audiogram.

Results:

Twenty-two hearing preservation candidates were implanted during an 18-month period (mean age 50 years; range 3-80) ending in December 2013. Thirteen patients (59.1%, mean age 45.6 years) received the oral prednisone taper while 9 (40.9%, mean age 56.3 years) did not. There was no significant age difference between the groups ( P = .18). Within the oral prednisone group, 84.6% of patients had at least a partial hearing preservation (23.1% complete preservation) compared with 33.3% (0% complete preservation) in those not taking prednisone ( P < .01).

Conclusions:

Oral steroids may play a role in low-frequency hearing preservation following cochlear implantation. Though the optimal protocol has yet to be identified, a 2-week oral prednisone taper given 3 days before surgery appears to positively impact the rate of and degree of preservation.

The limitations of computed tomography in adult cochlear implant evaluation

OBJECTIVE

To demonstrate the added value of magnetic resonance imaging (MRI) over computed tomography (CT) during adult cochlear implant evaluation.

PATIENTS

Two adult patients are discussed in whom MRI studies diagnosed bilateral vestibular schwannomas during cochlear implant candidacy evaluation.

INTERVENTIONS

Temporal bone CT and MRI.

MAIN OUTCOME MEASURE

Diagnosis of NF2.

RESULTS

Two adult patients, ages 67 and 68 years, were evaluated for cochlear implant candidacy. Both patients experienced slowly progressive, bilateral hearing loss without complaints of vertigo, and neither patient had a family history of hearing loss or neurogenic tumors. Both patients had near-symmetric pure tone thresholds on audiometric testing. An MRI and a CT scan were performed on both patients, and bilateral vestibular schwannomas were identified on MRI.

CONCLUSIONS

Though MRI is not routinely utilized in adult cochlear implant evaluation, it may be of greater clinical value than CT in the setting of adult-onset hearing loss. MRI allows for sensitive evaluation of cochlear patency and architecture, and cochlear nerve status. As demonstrated in the two index cases, MRI also provides the added benefit of evaluating for causes of retrocochlear hearing loss. These two patients would have likely experienced a significant delay in diagnosis of NF2 without preoperative MRI, particularly given the limitations of scanning following CI magnet placement.