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63 citation(s) found for "Patel, Neil".

Increase in cochlear implant electrode impedances with the use of electrical stimulation
Saoji, Aniket A. , Adkins, Weston J., Olund, Amy P., Graham, Madison, Patel, Neil S. , Neff, Brian A., Carlson, Matthew L. , Driscoll, Colin L. W., Graham, Madison

Mayo Clinic

International Journal of Audiology | August 4, 2020 | Volume: 59 | Issue: 11 | Pages: 881-888

10.1080/14992027.2020.1799251 | PMID 32749178 Get It

Cochlear implantation after radiosurgery for vestibular schwannoma
Patel, Neil , Carlson, Matthew L. , Link, Michael J. , Neff, Brian A., Driscoll, Colin L. W., Gompel, Jamie J. Van

Mayo Clinic

Journal of Neurosurgery | July 24, 2020 | Volume: 135 | Issue: 1 | Pages: 126-135

10.3171/2020.4.jns201069 | PMID 34250789 Get It

OBJECTIVE The object of this study was to ascertain outcomes of cochlear implantation (CI) following stereotactic radiosurgery (SRS) for vestibular schwannoma (VS). METHODS The authors conducted a retrospective chart review of adult patients with VS treated with SRS who underwent CI between 1990 and 2019 at a single tertiary care referral center. Patient demographics, tumor features, treatment parameters, and pre- and postimplantation audiometric and clinical outcomes are presented. RESULTS Seventeen patients (18 ears) underwent SRS and ipsilateral CI during the study period. Thirteen patients (76%) had neurofibromatosis type 2 (NF2). Median age at SRS and CI were 44 and 48 years, respectively. Median time from SRS to CI was 60 days, but notably, 4 patients underwent SRS and CI within 1 day and 5 patients underwent CI more than 7 years after SRS. Median marginal dose was 13 Gy. Median treatment volume at the time of SRS was 1400 mm 3 (range 84–6080 mm 3 , n = 15 patients). Median post-CI PTA was 28 dB HL, improved from 101 dB HL preoperatively (p < 0.001). Overall, 11 patients (12 ears) exhibited open-set speech understanding. Sentence testing was performed at a median of 10 months (range 1–143 months) post-CI. The median AzBio sentence score for patients with open-set speech understanding was 76% (range 19%–95%, n = 10 ears). Two ears exhibited Hearing in Noise Test (HINT) sentence scores of 49% and 95%, respectively. Four patients achieved environmental sound awareness without open-set speech recognition. Two had no detectable auditory percepts. CONCLUSIONS Most patients who underwent CI following SRS for VS enjoyed access to sound at near-normal levels, with the majority achieving good open-set speech understanding. Implantation can be performed immediately following SRS or in a delayed fashion, depending on hearing status as well as other factors. This strategy may be applied to cases of sporadic or NF2-associated VS.
Intracranial Epidural Abscess in a 9-Year-Old Boy With Precocious Puberty and Use of Continuous Positive Airway Pressure
Edlund, Wendy , Patel, Neil , Kotagal, Suresh , DeLone, David, Kotagal, Suresh , DeLone, David R.

Mayo Clinic

Journal of Child Neurology | March 30, 2020 | Volume: 35 | Issue: 8 | Pages: 509-511

10.1177/0883073820912047 | PMID 32223497 Get It

Intracranial extension of rhinosinusitis is rare in children. We report a 9-year-old immunocompetent boy with central precocious puberty and obstructive sleep apnea-hypopnea syndrome who developed an intracranial epidural abscess secondary to rhinosinusitis while on continuous positive airway pressure (CPAP) treatment. A retrospective review of the medical record and imaging studies was performed. MEDLINE and Cochrane databases were searched for reports of epidural abscess developing in patients receiving CPAP treatment or in patients with precocious puberty. Intracranial extension of frontal rhinosinusitis is more common during puberty probably because of the active growth of the frontal sinuses and their rich blood supply. Controlled studies show no increase with rhinosinusitis in adults on CPAP; no published studies assess intracranial extension of rhinosinusitis in CPAP use. Patients with unexplained, severe headache and fever following CPAP use may require neuroimaging (magnetic resonance imaging [MRI] / contrast computed tomography) to rule out intracranial extension of sinusitis.
Cochlear Implantation after Radiosurgery for Vestibular Schwannoma
Patel, Neil S. , Link, Michael J. , Neff, Brian A., Carlson, Matthew L. , Driscoll, Colin L. W.

Mayo Clinic

Journal of Neurological Surgery Part B: Skull Base | February 5, 2020 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1055/s-0040-1702462 Get It

The Influence of Vestibular Schwannoma Tumor Volume and Growth on Hearing Loss
Patel, Neil , Huang, Alice E. , Dowling, Eric M. , Lees, Katherine A. , Tombers, Nicole M. , Lohse, Christine M. , Marinelli, John P. , Neff, Brian A., Driscoll, Colin L. W., Link, Michael J. , Carlson, Matthew L. , Gompel, Jamie J. Van

Mayo Clinic

Otolaryngology–Head and Neck Surgery | January 28, 2020 | Volume: 162 | Issue: 4 | Pages: 530-537

10.1177/0194599819900396 | PMID 31986971 Get It

ObjectiveTo ascertain the relationship among vestibular schwannoma (VS) tumor volume, growth, and hearing loss.Study DesignRetrospective cohort study.SettingSingle tertiary center.Subjects and MethodsAdults with observed VS and serviceable hearing at diagnosis were included. The primary outcome was the development of nonserviceable hearing as estimated using the Kaplan‐Meier method. Associations of tumor volume with baseline hearing were assessed using Spearman rank correlation coefficients. Associations of volume and growth with the development of nonserviceable hearing over time were assessed using Cox proportional hazards models and summarized with hazard ratios (HRs).ResultsOf 230 patients with VS and serviceable hearing at diagnosis, 213 had serial volumetric tumor data for analysis. Larger tumor volume at diagnosis was associated with increased pure‐tone average (PTA) (P <. 001) and decreased word recognition score (WRS) (P =. 014). Estimated rates of maintaining serviceable hearing at 6 and 10 years following diagnosis were 67% and 49%, respectively. Larger initial tumor volume was associated with development of nonserviceable hearing in a univariable setting (HR for 1‐cm3 increase: 1.36, P =. 040) but not after adjusting for PTA and WRS. Tumor growth was not significantly associated with time to nonserviceable hearing (HR, 1.57; P =. 14), although estimated rates of maintaining serviceable hearing during observation were poorer in the group that experienced growth.ConclusionLarger initial VS tumor volume was associated with poorer hearing at baseline. Larger initial tumor volume was also associated with the development of nonserviceable hearing during observation in a univariable setting; however, this association was not statistically significant after adjusting for baseline hearing status.
Monitoring Cochlear Nerve Integrity During Vestibular Schwannoma Microsurgery in Real-Time Using Cochlear Implant Evoked Auditory Brainstem Response and Streaming Neural Response Imaging
Patel, Neil , Saoji, Aniket A. , Olund, Amy P., Carlson, Matthew L.

Mayo Clinic

Otology & Neurotology | January 10, 2020 | Volume: 41 | Issue: 2 | Pages: e201-e207

10.1097/mao.0000000000002458 | PMID 31923158 Get It

Objective: Intraoperative far-field auditory brainstem response (ABR) and direct cochlear nerve action potential monitoring using neural response imaging (NRI) are techniques for monitoring the cochlear nerve during vestibular schwannoma (VS) surgery. A new paradigm has developed where the cochlear nerve is anatomically preserved during tumor removal to facilitate cochlear implantation in select circumstances. This report describes the use of an unmodified commercial cochlear implant (CI) to elicit electrically-evoked direct cochlear nerve and far-field ABR monitoring to evaluate the status of the cochlear nerve during tumor resection in real time. Patients: Adult female with unilateral, sporadic VS. Intervention(s): Cochlear implantation followed by translabyrinthine resection of VS in single operation. Main Outcome Measures: During tumor resection intra-cochlear electrodes were used to deliver electrical stimulation and measure NRI or the cochlear nerve action potential. Electrically-evoked ABR (eABR) was measured using surface electrodes and wave V was monitored (far-field ABR) during surgery. Results: A 61-year-old female was evaluated for a unilateral, enlarging intracanalicular VS with asymmetric SNHL. The patient opted for microsurgery and due to her bilateral hearing loss was a candidate for CI. Cochlear implantation with an unmodified, commercially available lateral wall electrode was performed. The remainder of the approach and tumor resection was performed under continuous eABR and NRI monitoring. Gross total resection was achieved with intact eABR and NRI at the conclusion of the case. Changes in ABR and NRI consistently recovered after modifying dissection strategy. The patient reported auditory percepts with her cochlear implant postoperatively. Conclusions: This report demonstrates the feasibility of using real-time NRI and eABR with a CI to facilitate preservation of the cochlear nerve during VS microsurgery. Using this method to mitigate cochlear nerve trauma during microsurgery may preserve the option of CI for hearing rehabilitation.
Cochlear Implantation in Craniometaphyseal Dysplasia
Huang, Alice E. , Adkins, Weston J., Patel, Neil

Mayo Clinic

Otology & Neurotology | November 17, 2019 | Volume: 41 | Issue: 3 | Pages: e317-e321

10.1097/mao.0000000000002504 | PMID 31834875 Get It

Objective: Describe the first case of cochlear implantation (CI) for auditory rehabilitation of a patient with craniometaphyseal dysplasia (CMD) and progressive mixed hearing loss. Patients: A 65-year-old woman with known autosomal dominant CMD presented with progressive mixed hearing loss and declining benefit from conventional hearing aids. Computed tomography and magnetic resonance imaging revealed hyperostosis of the entire craniofacial skeleton. Hearing evaluation demonstrated pure-tone thresholds in the profound range bilaterally by air conduction, and bone conduction thresholds that matched aided thresholds for her left ear, though testing was somewhat limited by inability to mask at high air-conduction thresholds. CI candidacy testing confirmed poor word and sentence scores in the right ear. Intervention: Due to the inability to access the cochlea via a conventional mastoidectomy and facial recess approach, cochlear implantation via a postauricular subtotal petrosectomy approach with ear canal overclosure was performed. Main Outcome Measures: Post-implantation word and sentence testing. Results: Despite extensive internal auditory canal stenosis, the patient demonstrated excellent early speech understanding results 5 weeks after device activation. Postimplantation audiologic evaluation showed thresholds between 20 and 30 dB HL from 250 to 6000 Hz. Word and sentence testing scores were 76% Consonant-nucleus-consonant in quiet (up from 2% preoperatively) and 77% AzBio sentences in quiet (up from 10% preoperatively). Conclusion: This report describes the first description of CI for CMD. Despite the extensive radiologic abnormalities, the patient has demonstrated excellent benefit from implantation. Further study of rare temporal bone dysplasias, such as CMD, is critical to better characterize the progression of otologic disease and determine optimal treatment.
Durability of Hearing Preservation Following Microsurgical Resection of Vestibular Schwannoma
Dowling, Eric M. , Patel, Neil , Lohse, Christine M. , Driscoll, Colin L. W., Neff, Brian A., Link, Michael J. , Carlson, Matthew L. , Dowling, Eric M., Gompel, Jamie J. Van

Mayo Clinic

Otology & Neurotology | November 14, 2019 | Volume: 40 | Issue: 10 | Pages: 1363-1372

10.1097/mao.0000000000002378 | PMID 31725593 Get It

Objective:To ascertain long-term hearing outcomes in patients with serviceable hearing following microsurgical resection of sporadic vestibular schwannoma (VS).Study Design:Retrospective cohort.Setting:Tertiary academic referral center.Patients:Forty-three adult subjects with unilateral sporadic VS who had serviceable hearing (American Academy of Otolaryngology–Head and Neck Surgery [AAO-HNS] class A or B) on initial postoperative audiogram following microsurgical resection between 2003 and 2016 with a minimum of two postoperative audiograms available for review.Intervention:Surgical treatment with a retrosigmoid or middle cranial fossa approach.Main Outcome Measure:Rate of maintaining serviceable hearing, as estimated using the Kaplan–Meier method, in accordance with the 1995 and 2012 AAO-HNS guidelines on reporting hearing outcomes.Results:The median immediate postoperative pure-tone average (PTA) and word recognition score (WRS) were 31 dB and 95%, respectively. At last follow-up, the median PTA was 38 dB with a median change of 5 dB from initial postoperative audiogram, and the median WRS was 90% with a median change of 0% from initial postoperative audiogram. Eight patients developed non-serviceable hearing at a median of 4.1 years following microsurgical resection (interquartile range, 2.9–7.0). The median duration of hearing follow-up for the 35 patients who maintained serviceable hearing was 3.1 years (interquartile range, 2.2–7.5). Tumor control was achieved in 41 (95%) patients. The rate of maintaining serviceable hearing at 5 years was 81%.Conclusion:Microsurgical resection provides excellent tumor control and durable long-term hearing in those with AAO-HNS class A or B hearing postoperatively. The paradigm of proactive microsurgical resection—when the tumor is small and hearing is good—hinges on the surgeon's ability to preserve residual hearing in a very high percentage of cases at or near preoperative hearing levels to maintain an advantage over conservative observation with regard to long-term hearing preservation.
Multi-frequency Electrocochleography Measurements can be Used to Monitor and Optimize Electrode Placement During Cochlear Implant Surgery
Saoji, Aniket A. , Patel, Neil S. , Carlson, Matthew L. , Neff, Brian A., Koka, Kanthaiah , Tarigoppula, Venkata S Aditya , Driscoll, Colin L. W.

Mayo Clinic

Otology & Neurotology | October 23, 2019 | Volume: 40 | Issue: 10 | Pages: 1287-1291

10.1097/mao.0000000000002406 | PMID 31644474 Get It

Objective: To report the use of multi-frequency intra-cochlear electrocochleography (ECOG) in monitoring and optimizing electrode placement during cochlear implant surgery. An acoustic pure tone complex comprising of 250, 500, 1000, and 2000 Hz was used to elicit ECOG, or more specifically cochlear microphonics (CMs), responses from various locations in the cochlea. The most apical cochlear implant electrode was used as the recording electrode. Study Design: Clinical capsule report. Setting: Tertiary academic referral center. Results: ECOG measurements were performed during cochlear implant surgery in an adult patient with significant residual acoustic hearing. The 500, 1000, and 2000 Hz CM tracings from the most apical electrode showed an amplitude peak at three different instances during the early phase of cochlear implant electrode insertion. These results are consistent with the tonotopic organization of the cochlea. During final electrode placement a slight advancement of the electrode array resulted in a correlated decrease in 250, 500, and/or 1000 Hz CM amplitude. The electrode array was retracted and repositioned which resulted in a recovery of CM amplitude. Intraoperative CM thresholds revealed a correlation of r = 0.87 with preoperative audiometric thresholds. Conclusion: We present a report on simultaneous multi-frequency ECOG monitoring during cochlear implant surgery. Multi-frequency ECOG can be used to differentiate between electrode trauma and the advancement of the apical electrode beyond the CM source in the cochlea.
Involvement of the Cochlear Aqueduct by Jugular Paraganglioma Is Associated With Sensorineural Hearing Loss
Patel, Neil , Link, Michael J. , Driscoll, Colin L. W., Neff, Brian A., Lane, John I. , Carlson, Matthew L. , Gompel, Jamie J. Van

Mayo Clinic

Otology & Neurotology | August 30, 2019 | Volume: 40 | Issue: 9 | Pages: 1230-1236

10.1097/mao.0000000000002346 | PMID 31469795 Get It

Objective: The etiology of sensorineural hearing loss (SNHL) in patients with jugular paraganglioma (JP) whose tumors lack inner ear fistulae or vestibulocochlear nerve involvement is unknown. Recent literature has proposed that occlusion of the inferior cochlear vein may be causative. Herein, we assess the association between radiologic involvement of the cochlear aqueduct (CA) and the development of SNHL. Study Design: Blinded, retrospective review of imaging and audiometry. Setting: Tertiary center. Patients: Adults with JP. Intervention(s): None. Main Outcome Measures: Asymmetric SNHL was assessed continuously as the difference in bone conduction pure-tone average (BCPTA) between ears and as a categorical variable (≥15 dB difference at two consecutive frequencies, or a difference in speech discrimination score of ≥15%). Involvement of the CA was considered present if there was evidence of medial T2 fluid signal loss, contrast enhancement, or bony erosion/expansion. Results: Of 30 patients meeting inclusion criteria, 15 (50%) had asymmetric SNHL. CA involvement was observed in 87% of patients with asymmetric SNHL compared with 13% in those with symmetric hearing (p = 0.0001). Univariate analysis demonstrated that age, sex, and tumor volume were not associated with asymmetric SNHL. The median difference in BCPTA between ears in patients with CA involvement was 21.3 dB HL compared to 1.2 dB HL in those without CA involvement (p < 0.0001). Regression analysis demonstrates that enhancement within the CA is associated with a BCPTA difference of 19.4 dB HL (p = 0.0006). Conclusions: Cochlear aqueduct involvement by JP is associated with SNHL in the absence of inner ear fistula, vestibulocochlear nerve involvement, or brainstem compression. Correlation with operative findings or histopathologic evidence of tumor involvement may validate this intriguing imaging finding.