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Driscoll, Colin L. W.

A5106135006 | I1330342723

Mayo Clinic

Mayo Clinic

Citations 191

Survey of the American Neurotology Society on Cochlear Implantation: Part 1, Candidacy Assessment and Expanding Indications

Otology & Neurotology | November 28, 2017 | Volume: 39 | Issue: 1 | Pages: e12-e19

10.1097/mao.0000000000001632 | PMID 29210952

Objective: To examine practice variance of cochlear implant candidacy assessment and off-label indications across centers in the United States. Methods: Cross-sectional survey of the American Neurotology Society (ANS). Results: A total of 81 surveys were returned from ANS members who report regular involvement in cochlear implant care. Overall there was a broad distribution in age and clinical experience, with most respondents reporting ACGME accreditation in neurotology and employment at an academic center. The annual volume of cochlear implant surgeries varied considerably across centers. Seventy-eight percent of respondents performed cochlear implantation for at least one of the following indications within the last 2 years: profound hearing loss in children less than 12 months of age (35, 43%), children with asymmetrical hearing loss where at least one ear was better than performance cutoff for age (25, 31%), adults with asymmetrical hearing where at least one ear was better than the performance cutoff for adult criteria (49, 61%), single-sided deafness (37, 46%), and ipsilateral vestibular schwannoma (28, 35%). Centers with a higher annual implant volume more frequently performed off-label implantation in all queried populations (all, p≤0.001), and performed surgery on infants with congenital deafness at a younger age (p = 0.013), compared with centers with lower surgical volume. When surveyed regarding speech perception testing practices for adult candidacy assessment, 75 (100%) respondents who answered this question reported routine use of AzBio sentences, 42 (56%) CNC word scores, and 26 (35%) HINT testing; only 7 (9%) reported using BKB-SIN testing and 6 (8%) reported using CUNY scores. Fifty-one (68%) reported routine use of speech-in-noise testing to determine adult cochlear implant candidacy, 21 (28%) reported selective use only when patient scores were borderline in quiet, and 3 (4%) reported that their center does not currently use testing in noise for candidacy determination. Nineteen (26%) solely used +10 dB signal-to-noise ratio (SNR), 12 (16%) solely used +5 dB SNR, and 41 (55%) used both +10 and +5 dB SNR. Overall, 19% (N = 14) only perform unilateral implantation in the Medicare population, while 81% (N = 58) consider bilateral implantation. Conclusion: Significant variation in cochlear implant candidacy assessment and off-label implantation exists across centers and providers in the United States resulting in healthcare inequities. The high percentage of surgeons performing implantations for off-label or nontraditional indications reflects the overly restrictive and dated status of current implant guidelines. With greater adoption of more difficult speech perception testing in noise, careful clinical judgment is needed to maintain a favorable risk–benefit balance for prospective implant candidates.
Survey of the American Neurotology Society on Cochlear Implantation: Part 2, Surgical and Device-Related Practice Patterns

Otology & Neurotology | November 28, 2017 | Volume: 39 | Issue: 1 | Pages: e20-e27

10.1097/mao.0000000000001631 | PMID 29210943

Objective: To examine surgical and device-related cochlear implant practice patterns across centers in the United States. Methods: Cross-sectional survey of the American Neurotology Society (ANS). Results: A total of 81 surveys were returned from ANS members who report regular involvement in cochlear implant care. Overall there was a broad distribution in age and clinical experience, with most respondents reporting Accreditation Council for Graduate Medical Education (ACGME) accreditation in neurotology and employment at an academic center. The annual volume of cochlear implant surgeries varied considerably across centers. Eighty percent of respondents report to offer all three Food and Drug Administration (FDA) approved device brands at their center. In cases where hearing preservation is not a goal, 56% of respondents prefer a perimodiolar electrode design, while 44% prefer a lateral wall electrode. With regard to insertion technique for scala tympani access, 64% prefer inserting through the round window (RW) membrane, 26% prefer an extended round window (ERW) approach, while only 10% prefer a cochleostomy. In cases where hearing preservation is a goal of surgery, 86% of respondents prefer a lateral wall electrode design, while only 14% prefer a perimodiolar electrode design. With regard to insertion technique, 86% prefer RW insertion, while only 9% prefer an ERW approach, and only 5% prefer a cochleostomy. Respondents who prefer RW electrode insertion more commonly use a lateral wall electrode, whereas those who prefer an ERW or cochleostomy approach more commonly use a periomodiolar electrode (p < 0.001). There was a statistically significant greater number of surgeons that prefer lateral wall electrodes (p < 0.001) and RW insertion (p < 0.001) for hearing preservation cases compared with non-hearing preservation cases. For implantation of a hypothetical patient with significant residual hearing, within the range of hybrid device candidacy, the great majority of surgeons prefer a conventional length electrode and only 29% prefer to implant a hybrid device. In cases where hearing preservation is a goal, the overwhelming majority of respondents (96%, n = 74) reported using at least one form of steroid application. Ninety-two percent (n = 71) used intraoperative intravenous steroids, 55% (n = 42) prescribed postoperative oral steroids, 44% (n = 34) bathed the middle ear with steroids during surgery, and 30% (n = 23) prescribed preoperative oral steroids. Together, 65% of respondents use a variation of the tight subperiosteal pocket technique for internal device fixation, 19% prefer a bony well and trough with tie-downs, 10% prefer a bony well and trough without tie-downs, and 5% prefer a screw fixation system. Of the 50 who prefer utilizing a subperiosteal pocket, 31 (62%) incorporate a bony trough and 19 (38%) perform a subperiosteal pocket alone without a bony trough. Conclusion: The results of this survey reflect the evolution in surgical and device-related preferences for cochlear implantation in the United States. An increasing number of surgeons prefer the RW approach for electrode insertion. When hearing preservation is not a goal, there is a near even preference for lateral wall and perimodiolar electrode designs; however, the great majority of surgeons prefer a lateral wall design when attempting to preserve residual acoustic hearing. Even in cases where substantial residual hearing exists, many surgeons prefer conventional length electrodes to hybrid designs. These changes reflect the prioritization of atraumatic surgery and parallel the development of thinner and more atraumatic electrodes.
Reply to Letter to the Editor: Paget's Disease of the Temporal Bone: A Single-Institution Contemporary Review of 27 Patients

Otology & Neurotology | September 7, 2017 | Volume: 38 | Issue: 10 | Pages: 1547-1548

10.1097/mao.0000000000001562 | PMID 28891874

Diagnosing Large Vestibular Aqueduct: Radiological Review of High-Resolution CT Versus High-Resolution Volumetric MRI

Otology & Neurotology | June 9, 2017 | Volume: 38 | Issue: 7 | Pages: 948-955

10.1097/mao.0000000000001482 | PMID 28604576

Objectives: To compare the diagnostic yield of high-resolution volumetric T2-weighted MRI (HRT2-MRI) with high-resolution computed tomography (HRCT) for diagnosis of large vestibular aqueduct (LVA). Study Design: Three board-certified neuroradiologists performed an independent, blinded radiological review for diagnosing LVA with 2:1 age-matched controls on patients with both HRCT and HRT2-MRI imaging. Setting: Tertiary referral center. Patients: All patients between 2002 and 2016 with hearing loss who underwent both HRCT and HRT2-MRI and were diagnosed with LVA on either modality. Main Outcome Measures: Concordance rate for LVA between HRCT and HRT2-MRI. Results: Concordance rate for HRCT and HRT2-MRI for diagnosing LVA was 88% (124/141) when assessing both the midpoint and external aperture diameters. Fifteen ears had LVA on computed tomography (CT), but not on magnetic resonance imaging (MRI); in comparison, two ears had LVA on MRI, but not on CT (p = 0.002). Excellent inter-rater reliability among the three radiologists was demonstrated. Conclusion: Historically, HRCT has been the imaging modality of choice for diagnosing LVA. Although a higher concordance rate of HRT2-MRI was found compared with previous studies utilizing earlier MRI technology, HRCT still detected a larger number of patients with clinically significant hearing loss compared with MRI. Given the high concordance rate and efficacy of both modalities in diagnosing LVA, the ultimate decision of which modality to choose may depend on other patient-specific and clinical factors.
Long-term risk of recurrence and regrowth after gross-total and subtotal resection of sporadic vestibular schwannoma

Journal of Neurosurgery | May 19, 2017 | Volume: 133 | Issue: 4 | Pages: 1052-1058

10.3171/2016.11.jns16498 | PMID 28524795

OBJECTIVEThe management of vestibular schwannoma (VS) remains controversial. One commonly cited advantage of microsurgery over other treatment modalities is that tumor removal provides the greatest chance of long-term cure. However, there are very few publications with long-term follow-up to support this assertion. The purpose of the current study is to report the very long-term risk of recurrence among a large historical cohort of patients who underwent microsurgical resection.METHODSThe authors retrospectively reviewed the medical records of patients who had undergone primary microsurgical resection of unilateral VS via a retrosigmoid approach performed by a single neurosurgeon-neurotologist team between January 1980 and December 1999. Complete tumor removal was designated gross-total resection (GTR), and anything less than complete removal was designated subtotal resection (STR). The primary end point was radiological recurrence-free survival. Time-to-event analyses were performed to identify factors associated with recurrence.RESULTSFour hundred fourteen patients met the study inclusion criteria and were analyzed. Overall, 67 patients experienced recurrence at a median of 6.9 years following resection (IQR 3.9–12.1, range 1.2–22.5 years). Estimated recurrence-free survival rates at 5, 10, 15, and 20 years following resection were 93% (95% CI 91–96, 248 patients still at risk), 78% (72–85, 88), 68% (60–77, 47), and 51% (41–64, 22), respectively. The strongest predictor of recurrence was extent of resection, with patients who underwent STR having a nearly 11-fold greater risk of recurrence than the patients treated with GTR (HR 10.55, p < 0.001). Among the 18 patients treated with STR, 15 experienced recurrence at a median of 2.7 years following resection (IQR 1.9–8.9, range 1.2–18.7). Estimated recurrence-free survival rates at 5, 10, 15, and 20 years following GTR were 96% (95% CI 93–98, 241 patients still at risk), 82% (77–89, 86), 73% (65–81, 46), and 56% (45–70, 22), respectively. Estimated recurrence-free survival rates at 5, 10, and 15 years following STR were 47% (95% CI 28–78, 7 patients still at risk), 17% (5–55, 2), and 8% (1–52, 1), respectively.CONCLUSIONSLong-term surveillance is required following microsurgical resection of VS even after GTR. Subtotal resection alone should not be considered a definitive long-term cure. These data emphasize the importance of long-term follow-up when reporting tumor control outcomes for VS.
Paget's Disease of the Temporal Bone: A Single-Institution Contemporary Review of 27 Patients

Otology & Neurotology | May 12, 2017 | Volume: 38 | Issue: 6 | Pages: 907-915

10.1097/mao.0000000000001430 | PMID 28498272

Objectives: To report a contemporary review from a single-institution series on Paget's disease of the temporal bone (PDTB). Study Design: Retrospective chart review of patients evaluated from 1998 to 2016. Setting: Quaternary referral center. Patients: Patients with radiographically confirmed PDTB. Main Outcome Measures: Clinical, audiological, and radiological features and management strategies of PDTB. Results: A total of 50 temporal bones in 27 patients (15 men) were diagnosed with PDTB. Symptoms at presentation included hearing loss (n = 23, 85%), headache (n = 18, 67%), dizziness (n = 14, 52%), tinnitus (n = 5, 19%), chronic otitis media (n = 2, 7%), hemifacial spasm without facial paralysis (n = 1, 4%), multiple cranial neuropathies (n = 1, 4%), and neoplastic transformation (n = 1, 4%). Of the 23 ears with audiometric data available for review, 65% exhibited sensorineural hearing loss, and 35% mixed hearing loss. Long-term audiometric follow-up was available on two patients, both of whom demonstrated hearing loss at a rate greater than would be expected for normal aging. Two patients underwent successful cochlear implantation, achieving open-set speech recognition. Radiographic features of temporal bone involvement are reviewed and illustrated. Conclusion: This is the largest single-institution clinical series examining patients with PDTB in the English literature. Variable patterns of temporal bone involvement by Paget's disease are observed leading to a diverse set of clinical symptoms, including slowly progressive hearing loss, tinnitus, compressive cranial neuropathies, and benign or malignant tumorigenesis. Involvement typically begins in the petrous apex and progresses laterally. Otic capsule bone demineralization occurs late in the disease process. Cochlear implantation appears to be an effective management strategy for patients with severe-to-profound hearing loss.
Quality of Life in Patients with Vestibular Schwannomas Following Gross Total or Less than Gross Total Microsurgical Resection: Should We be Taking the Entire Tumor Out?

Neurosurgery | April 11, 2017 | Volume: 82 | Issue: 4 | Pages: 541-547

10.1093/neuros/nyx245 | PMID 29554375

Abstract BACKGROUND The goal of microsurgical removal of a vestibular schwannoma is to completely remove the tumor, to provide long-term durable cure. In many cases, less than gross total resection (GTR) is performed to preserve neurological, and especially facial nerve function. OBJECTIVE To analyze long-term quality of life (QoL) in a cohort of patients who received either GTR or less than GTR. METHODS Patients operated for vestibular schwannoma less than 3.0 cm in posterior fossa diameter at 1 of 2 international tertiary care centers were surveyed using generic and disease-specific QoL instruments. RESULTS A total of 143 patients were analyzed. GTR was performed in 122, and 21 underwent less than GTR. QoL was assessed at a mean of 7.7 yr after surgery (interquartile range: 5.7-9.6). Patients who underwent GTR had smaller tumors; otherwise, there were no baseline differences between groups. Patients who underwent GTR, after multivariable adjustment for baseline features and facial nerve and hearing outcomes, reported statistically significantly better Short Form Health Survey-36 (SF-36) physical and mental scores, Patient-Reported Outcomes Measurement Information System (PROMIS-10) physical and mental scores, and Penn Acoustic Neuroma Quality of Life (PANQOL) facial, energy, general health, and total scores compared to patients receiving less than GTR. CONCLUSION GTR is associated with better QoL using the general QoL measures SF-36 and PROMIS-10 and the disease-specific PANQOL, even after controlling for baseline and outcome differences. This is especially significant in the assessment of mental health, indicating there may indeed be a psychological advantage to the patient that translates to overall well-being to have the entire tumor removed if microsurgical resection is undertaken.
Microsurgery for Recurrent Vestibular Schwannoma After Previous Gross Total Resection

Otology & Neurotology | April 7, 2017 | Volume: 38 | Issue: 6 | Pages: 882-888

10.1097/mao.0000000000001402 | PMID 28595258

Objective: To present a single-institution experience and supportive systematic literature review examining outcomes after repeat microsurgery for recurrent vestibular schwannoma (VS) following previous gross total resection (GTR). Study Design: Retrospective review of prospectively maintained VS database. Systematic literature review. Setting: Tertiary referral center. Patients: Six proven VS recurrences after primary GTR, treated via repeat microsurgery. Intervention: Repeat microsurgery. Main Outcome Measures: Facial nerve function, extent-of-resection, time-to-repeat surgery, same versus alternate approach at repeat surgery (relative to primary operation). Results: GTR was achieved in four (67%). House–Brackmann (HB) grade I–II facial nerve function was achieved in five (87%), including one that improved from preoperative HB grade V. An alternate surgical approach was chosen in four (67%). Systematic review identified four studies documenting 50 cases with patient-specific outcomes after repeat microsurgery for recurrent VS. Our cohort had significantly longer mean time-to-repeat surgery (117 vs. 64 months, p = 0.03), was significantly less likely to have HB III–VI function postrepeat (17% vs. 68%, p = 0.04), and was significantly less likely to undergo same approach surgery (33% vs. 90%, p = 0.0002); rates of GTR were nonsignificant (67% vs. 94%, p = 0.1). Conclusion: We report a six-patient series of microsurgery for recurrent VS after GTR, and the first systematic review of this rare and challenging entity. Anecdotally, our findings suggest that an alternate surgical approach may facilitate easier access to the tumor, with less scar encountered during the approach. Our results confirm that repeat microsurgery for recurrent VS is safe and effective, even for larger tumors not typically amenable to stereotactic radiosurgery.
Health-related quality of life outcomes following adult cochlear implantation: A prospective cohort study

Cochlear Implants International | March 31, 2017 | Volume: 18 | Issue: 3 | Pages: 130-135

10.1080/14670100.2017.1293203 | PMID 28248612

Microsurgery for Recurrent Vestibular Schwannoma after Previous Gross Total Resection

Journal of Neurological Surgery Part B: Skull Base | March 3, 2017 | Volume: 78 | Issue: S 01 | Pages: S1-S156

10.1055/s-0037-1600885