OBJECTIVE The authors’ objective was to reevaluate the role of microsurgery for epidermoid tumors by examining the associations between extent of resection (EOR), tumor control, and clinical outcomes. METHODS This was a retrospective study of patients with microsurgically treated intracranial epidermoid tumors. The recurrence-free and intervention-free rates were calculated using the Kaplan-Meier method. EOR was graded as gross-total resection (GTR) (total resection without residual on MRI), near-total resection (NTR) (a cyst lining was left in place), subtotal resection (STR) (> 90% resection), and partial resection (PR) (any other suboptimal resection) and used to stratify outcomes. RESULTS Sixty-three patients with mean clinical and radiological follow-up periods of 87.3 and 81.8 months, respectively, were included. Sixteen patients underwent second resections, and 5 underwent third resections. The rates of GTR/NTR, STR, and PR were 43%, 35%, and 22%, respectively, for the initial resections; 44%, 13%, and 44% for the second resections; and 40%, 0%, and 60% for the third resections (p < 0.001). The 5- and 10-year cumulative recurrence-free rates after initial resection were 64% and 32%, respectively. When stratified according to EOR, the 10-year recurrence-free rate after GTR/NTR was marginally better than that after STR (61% vs 35%, p = 0.130) and significantly better than that after PR (61% vs 0%, p < 0.001). The recurrence-free rates after initial microsurgery were marginally better than those after second surgery (p = 0.102) and third surgery (p = 0.065). The 5- and 10-year cumulative intervention-free rates after initial resection were 91% and 58%, respectively. When stratified according to EOR, the 10-year intervention-free rate after GTR/NTR was significantly better than that after STR (100% vs 51%, p = 0.022) and PR (100% vs 27%, p < 0.001). The 5-year intervention-free rate after initial surgery was marginally better than that after second surgery (52%, p = 0.088) and significantly better than that after third surgery (0%, p = 0.004). After initial, second, and third resections, permanent neurological complications were observed in 6 (10%), 1 (6%), and 1 (20%) patients, respectively. At the last follow-up visit, 82%, 23%, and 7% of patients were free from radiological recurrence after GTR/NTR, STR, and PR as the initial surgical procedure, respectively. CONCLUSIONS GTR/NTR seems to contribute to better disease control without significantly impairing functional status. Initial resection offers the best chance to achieve better EOR, leading to better disease control.
Defining clinically significant tumor size in vestibular schwannoma to inform timing of microsurgery during wait-and-scan management: moving beyond minimum detectable growth
Journal of Neurosurgery | October 15, 2021 | Volume: 136 | Issue: 5 | Pages: 1289-1297
OBJECTIVE Detection of vestibular schwannoma (VS) growth during observation leads to definitive treatment at most centers globally. Although ≥ 2 mm represents an established benchmark of tumor growth on serial MRI studies, 2 mm of linear tumor growth is unlikely to significantly alter microsurgical outcomes. The objective of the current work was to ascertain where the magnitude of change in clinical outcome is the greatest based on size. METHODS A single-institution retrospective review of a consecutive series of patients with sporadic VS who underwent microsurgical resection between January 2000 and May 2020 was performed. Preoperative tumor size cutpoints were defined in 1-mm increments and used to identify optimal size thresholds for three primary outcomes: 1) the ability to achieve gross-total resection (GTR); 2) maintenance of normal House-Brackmann (HB) grade I facial nerve function; and 3) preservation of serviceable hearing (American Academy of Otolaryngology–Head and Neck Surgery class A/B). Optimal size thresholds were obtained by maximizing c-indices from logistic regression models. RESULTS Of 603 patients meeting inclusion criteria, 502 (83%) had tumors with cerebellopontine angle (CPA) extension. CPA tumor size was significantly associated with achieving GTR, postoperative HB grade I facial nerve function, and maintenance of serviceable hearing (all p < 0.001). The optimal tumor size threshold to distinguish between GTR and less than GTR was 17 mm of CPA extension (c-index 0.73). In the immediate postoperative period, the size threshold between HB grade I and HB grade > I was 17 mm of CPA extension (c-index 0.65). At the most recent evaluation, the size threshold between HB grade I and HB grade > I was 23 mm (c-index 0.68) and between class A/B and C/D hearing was 18 mm (c-index 0.68). Tumors within 3 mm of the 17-mm CPA threshold displayed similarly strong c-indices. Among purely intracanalicular tumors, linear size was not found to portend worse outcomes for all measures. CONCLUSIONS The probability of incurring less optimal microsurgical outcomes begins to significantly increase at 14–20 mm of CPA extension. Although many factors ultimately influence decision-making, when considering timing of microsurgical resection, using a size threshold range as depicted in this study offers an evidence-based approach that moves beyond reflexively recommending treatment for all tumors after detecting ≥ 2 mm of tumor growth on serial MRI studies.
Global Incidence of Sporadic Vestibular Schwannoma: A Systematic Review
Otolaryngology–Head and Neck Surgery | August 31, 2021 | Volume: 167 | Issue: 2 | Pages: 209-214
ObjectiveUbiquitous throughout the literature and during patient counseling, vestibular schwannoma is often quoted to affect about 1 per 100,000 people. Yet, reports from distinct international populations suggest that the incidence is likely much higher. The objective of the current work was to systematically characterize the global incidence of sporadic vestibular schwannoma.Data SourcesScopus, Embase, and PubMed.Review MethodsPopulation‐based studies reporting incidence rates of sporadic vestibular schwannoma between January 2010 and August 2020 were searched with language restrictions requiring reports to be published in Chinese, English, German, Italian, or Spanish. The protocol was registered with PROSPERO (CRD42021228208) prior to commencement of data collection. PRISMA guidelines for transparent reporting of systematic reviews were followed.ResultsAmong 424 citations, 6 publications covering 4 distinct populations from Denmark, the Netherlands, Taiwan, and the United States met inclusion criteria. Most recent incidence rates of among all ages ranged between 3.0 and 5.2 per 100,000 person‐years. Highest incidence rates were reported among patients aged ≥70 years, peaking at 20.6 per 100,000 person‐years. One study from the United States reported the incidence of asymptomatic, incidentally diagnosed tumors at a rate of 1.3 per 100,000 person‐years from 2012 to 2016.ConclusionsRecent international incidence rates of sporadic vestibular schwannoma exceed the commonly quoted “1 per 100,000” figure by up to 5‐fold among all ages and by up to 20‐fold among age groups at highest risk. Based on modern incidence rates, the lifetime prevalence of developing sporadic vestibular schwannoma likely exceeds 1 per 500 persons.
Development of the National Otolaryngology Interest Group: Conception to Implementation
Otolaryngology–Head and Neck Surgery | August 3, 2021 | Volume: 166 | Issue: 3 | Pages: 413-416
Otolaryngology is a small and highly sought‐after surgical subspecialty with sparse residency positions, making it competitive to match into. Allopathic (MD) students without home otolaryngology residency programs, osteopathic (DO) medical students, and underrepresented minorities have historically faced additional challenges in matching into otolaryngology. These specific populations generally experience limited opportunities in establishing mentors, engaging in scholarly activity, and gaining early exposure to clinical settings. Even though the American Osteopathic Association and the Accreditation Council for Graduate Medical Education merger was in part established to create equity among applicants, there remains a substantial disparity among the match rates of medical students of various educational and cultural backgrounds. The National Otolaryngology Interest Group is a student‐led interest group created to provide all medical students, especially those facing barriers, with the resources needed to best prepare for matching into an otolaryngology residency program and ultimately a career in otolaryngology.
Lifetime Cost and Quality-Adjusted Life-Years Across Management Options for Small- and Medium-Sized Sporadic Vestibular Schwannoma
Objective: Despite the growing emphasis on healthcare costs, limited data address this aspect of care within the vestibular schwannoma (VS) literature. We sought to determine which strategy confers the lowest lifetime cost and greatest quality-adjusted life-years (QALYs) for patients with small- to medium-sized sporadic VS tumors. Study Design: A Markov model was created to determine the most cost-effective management algorithm. Tumor characteristics, magnetic resonance imaging surveillance schedule, treatment outcomes, and health-related quality of life values were derived from previously published data. Cost estimates were based on CMS Fee Schedule reimbursement rates. Setting: Economic Evaluation Service within the Kern Center for the Science of Healthcare Delivery. Patients: Patients diagnosed with small- to medium-sized sporadic VS. Interventions: Upfront microsurgery following diagnosis, upfront radiosurgery following diagnosis, observation with microsurgery reserved for observed tumor growth, and observation with radiosurgery reserved for observed tumor growth. Results: Across patient ages at time of diagnosis ranging from 18 to 70 years, observation with subsequent radiosurgery used for tumor growth was the most cost-effective management algorithm while upfront microsurgery was the least. When presented with a hypothetical 50-year-old patient, the strategy with the lowest lifetime cost and highest QALYs was observation with subsequent radiosurgery reserved for tumor growth ($32,161, 14.11 QALY), followed by observation with microsurgery reserved for tumor growth ($34,503, 13.94 QALY), upfront radiosurgery ($43,456, 14.02 QALY), and lastly, upfront microsurgery ($47,252, 13.60 QALY). Sensitivity analyses varying mortality rates, estimated costs, health-related quality of life, and progression to nonserviceable hearing demonstrated consistent ranking among treatments. Conclusions: When considering initial management of small- and medium-sized sporadic VSs, neither lifetime cost nor QALYs support upfront microsurgery or radiosurgery, even for younger patients. Initial observation with serial imaging, reserving radiosurgery or microsurgery for patients exhibiting tumor growth, confers the greatest potential for optimized lifetime healthcare cost and QALY outcomes.
Does early activation within hours after cochlear implant surgery influence electrode impedances?
International Journal of Audiology | July 18, 2021 | Volume: 61 | Issue: 6 | Pages: 520-525
ObjectiveTo evaluate patients who become symptomatic from superior semicircular canal dehiscence (SSCD) following head trauma.Study DesignCase series assessing patients presenting with SSCD after a trauma.MethodsA case series was completed assessing patients presenting with SSCD after trauma. Data from three academic medical centers were evaluated, including the following: imaging, videonystagmography (VNG)/vestibular evoked myogenic potential (VEMP) testing, audiometric assessment, and surgical repair. Outcome measures included the following: 1) Description of audio‐vestibular symptoms, 2) mean pre‐ and post‐operative pure tone average (PTA), word recognition score (WRS), and air bone gap (ABG).ResultsA total of 14 patients were included; 86% were male. Approximately 43% were found to have bilateral SSCD on imaging, with 57% of patients pursuing surgical management. The most common presenting symptoms included pulsatile tinnitus (93%), autophony (79%), and hearing loss (64%). Approximately 36% of patients underwent VNG/VEMP testing, with 83.3% of those demonstrating abnormal results. The mean audiometric findings on the symptomatic side included an air‐conduction PTA of 38.0 dB, bone‐conduction PTA of 24.3 dB, WRS of 81%, and ABG of 17.9 dB. Among patients who underwent surgery (57%), there was no significant change in the air‐conduction PTA, bone‐conduction PTA, or WRS (P > .05). However, there was an improvement in the ABG (preoperative = 22.8 dB versus postoperative = 9.7 dB; P = .005).ConclusionHead trauma may be a potentiating event for SSCD syndrome. This study advances the hypothesis that these patients likely have underlying radiographic SSCD prior to their trauma, and a traumatic event increases in intra‐vestibular or intracranial pressures, unmasking SSCD syndrome.Level of Evidence4 Laryngoscope, 131:E2810–E2818, 2021
Tympanic Membrane Pneumatocele from Auto-insufflation
Annals of Otology, Rhinology & Laryngology | June 18, 2021 | Volume: 131 | Issue: 5 | Pages: 551-554
Objective: The differential of an external auditory canal mass is broad. One rare potential cause is a pneumatocele of the tympanic membrane, which has only been described 1 other time in the literature. This report serves to describe the second case of this pathology, including its unique presentation, and benign clinical course. Methods: Case report. Results: A case is discussed in which a pneumatocele of the tympanic membrane was incidentally identified during evaluation of contralateral otologic pathology. The etiology was suspected to be habitual auto-insufflation. After cessation of this practice, the pneumatocele was noted to resolve without further intervention. Conclusion: A tympanic membrane pneumatocele represents a rare cause of an external auditory canal mass. The diagnosis can be made clinically via history, palpation, and otoscopy during auto-insufflation, potentially avoiding further diagnostic testing. Depending on the etiology, resolution can occur after lifestyle modification; however, further interventions may definitively treat the condition if so required.
Natural History of Growing Sporadic Vestibular Schwannomas During Observation: An International Multi-Institutional Study
Objective: Active treatment of small- or medium-sized vestibular schwannoma during wait-and-scan management is currently recommended at most centers globally once growth is detected. The primary aim of the current study was to characterize the natural history of growing sporadic vestibular schwannoma during observation. Study Design: Cohort study. Setting: Four tertiary referral centers across the United States and Denmark. Patients: Patients with two prior MRI scans demonstrating ≥2 mm of linear growth who continued observational management. Intervention: Observation with serial imaging. Main Outcome Measure: Subsequent linear growth-free survival (i.e., an additional ≥2 mm of growth) following initial growth of ≥2 mm from tumor size at diagnosis. Results: Among 3,402 patients undergoing observation, 592 met inclusion criteria. Median age at initial growth was 66 years (IQR 59–73) for intracanalicular tumors (N = 65) and 62 years (IQR 54–70) for tumors with cerebellopontine angle extension (N = 527). The median duration of MRI surveillance following initial detection of tumor growth was 5.2 years (IQR 2.4–6.9) for intracanalicular tumors and 1.0 year (IQR 1.0–3.3) for cerebellopontine angle tumors. For intracanalicular tumors, subsequent growth-free survival rates (95% CI; number still at risk) at 1, 2, 3, 4, and 5 years following the initial MRI that demonstrated growth were 77% (67–88; 49), 53% (42–67; 31), 46% (35–60; 23), 34% (24–49; 17), and 32% (22–47; 13), respectively. For cerebellopontine angle tumors, subsequent growth-free survival rates were 72% (68–76; 450), 47% (42–52; 258), 32% (28–38; 139), 26% (21–31; 82), and 22% (18–28; 57), respectively. For every 1 mm increase in magnitude of growth from diagnosis to tumor size at detection of initial growth, the HRs associated with subsequent growth were 1.64 (95% CI 1.25–2.15; p < 0.001) for intracanalicular tumors and 1.08 (95% CI 1.01–1.15; p = 0.02) for cerebellopontine angle tumors. Conclusions: Growth detected during observation does not necessarily portend future growth, especially for slowly growing tumors. Because early treatment does not confer improved long-term quality of life outcomes, toleration of some growth during observation is justifiable in appropriately selected cases.
Differential Impact of Advanced Age on Clinical Outcomes After Vestibular Schwannoma Resection in the Very Elderly: Cohort Study
Abstract BACKGROUND Vestibular schwannomas (VS) have a peak incidence in the sixth and seventh decades of life. Stereotactic radiosurgery is often the preferred treatment for VS among patients of advanced age. The fraction of elderly patients potentially requiring consideration for surgical treatment is anticipated to expand, mandating an update to management paradigms in this population. OBJECTIVE To describe our experience with surgical management of VS in patients aged 75 yr and older. METHODS Cohort study of all patients aged ≥75 yr with sporadic VS requiring surgical treatment at our institution between 1999 and 2020. Data included preoperative baseline characteristics and outcome data including extent of resection, facial nerve and hearing status, functional outcome, length of stay, and complications. RESULTS A total of 24 patients were included, spanning an age range of 75 to 90 yr. Average tumor size was 2.76 ± 1.04 cm, and average baseline Modified 5-item Frailty Index (mFI-5) score was 1.08 ± 0.93. Extent of resection was gross total in 5 (20.8%), near total in 3 (12.5%), and sub-total resection in the remaining 16 (66.7%). One patient died in the postoperative period because of an acute sub-dural hematoma. Favorable facial nerve function (HB1-2) was preserved in 12 patients (75%) between 75 and 79 yr and 2 patients (28.6%) aged ≥ 80 yr. No cerebrospinal fluid leak or surgical site infection was observed; 3 patients developed hydrocephalus requiring ventriculo-peritoneal shunt placement. Nine patients required out-of-home disposition; all patients eventually returned to independent living. CONCLUSION Microsurgical resection of VS can be safely undertaken in patients greater than 75 y/o but may carry an increased risk of poor facial function.