Patel, Neil S.

Abstract 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.

AbstractObjectiveTo characterize normative adult ranges for cochlear promontory thickness relevant to the development of subendosteal and transpromontory electrodes to rehabilitate various neurotologic disorders.PatientsAdults (≥18 years).InterventionIn vivo radiologic assessment using a 192‐slice CT scanner (Force‐192; Siemens Healthcare) with ultrahigh‐resolution scan mode combined and iterative reconstruction.Main Outcome MeasureCochlear promontory thickness.ResultsAmong 48 included patients (96 ears), the mean (SD) age was 56 (18) years (range 25–94) and included 25 (52%) women. Of that 12 patients (25%) had osteopenia (n = 6) or osteoporosis (n = 6). The mean (SD) body mass index was 28 (5) kg/m2. The mean (SD) promontory thickness for the 96 temporal bones under study was 1.22 (0.24) mm (range 0.55–1.85). There was not a statistically significant association between age and promontory thickness (correlation coefficient .08; p = .44). Promontory thickness was significantly greater for men than women (mean 1.28 vs. 1.17 mm; p = .03) and increased with increasing body mass index (correlation coefficient .30; p = .004). Last, promontory thickness was significantly less for patients with osteopenia or osteoporosis compared with those without these conditions (mean 1.09 vs. 1.27 mm; p = .002).ConclusionsCochlear promontory thickness can vary by almost 1.5 mm across patients and is significantly associated with patient sex, body mass index, and comorbid osteopenia/osteoporosis. Subendosteal and transpromontory electrode placement techniques must account for this degree of variability.Level of EvidenceIV

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

ObjectiveThe degree to which various treatment modalities modify vestibular schwannoma (VS)–associated symptoms has received limited attention. The purpose of this study was to determine how different treatment modalities affect subjective symptoms in those presenting with VS.Study DesignProspective survey.SettingTertiary neurotology referral center.MethodsPatients with sporadic VS who received treatment at our institution were prospectively surveyed with a VS symptom questionnaire. Those who completed a baseline survey prior to treatment and at least 1 posttreatment survey were included. The prospective survey evaluated the severity of self‐reported symptoms (Likert scale, 1‐10), including tinnitus, dizziness or imbalance, headaches, and hearing loss.ResultsA total of 244 patients were included (mean age, 57 years). The mean duration of follow‐up was 2.1 years, and the median number of surveys completed was 2 (interquartile range, 1‐3). Seventy‐eight (32%) cases were managed with observation, 118 (48%) with microsurgery, and 48 (20%) with radiosurgery. Multivariable analyses revealed no statistically significant difference in the change in tinnitus (P =. 15), dizziness or imbalance (P = 0.66), or headaches (P =. 24) among treatment groups. Evaluation of clinically important differences demonstrated that microsurgery leads to significant bidirectional changes in headaches.ConclusionsLimited prospective data exist regarding the progression or resolution of subjective symptoms in those presenting with VS. This study suggests that tinnitus, dizziness or imbalance, and headaches are unlikely to be significantly modified by treatment modality and generally should not be used to direct treatment choice.

Objective: To evaluate adverse events and feasibility of performing 1.5-T MRI in patients with cochlear implants (CI) and auditory brainstem implants (ABI). Setting: Single tertiary academic referral center. Patients: CI and ABI recipients undergoing 1.5-T MRI without internal magnet removal. Intervention(s): MRI after tight headwrap application. Main Outcome Measures: Adverse events, patient tolerance. Results: A total of 131 MR studies in 79 patients were performed, with a total of 157 study ears. Sixty-one patients (77%) had unilateral devices. Four patients (5%) underwent MRI with ABI magnets in place. Sixteen patients (20%) had MRI-compatible devices that did not require a head wrap. There were no instances of device stimulation, device malfunction, or excessive heating of the receiver-stimulator package. Magnet tilt requiring manual repositioning occurred during seven studies (4.5%) and magnet displacement requiring operative intervention occurred during seven studies (4.5%). Significant pain where imaging had to be discontinued occurred during three episodes (2%). No adverse events were noted among patients who underwent MRI with an MRI-compatible magnet. Conclusions: MRI with CI or ABI magnets in place is associated with a low prevalence of adverse events when performed in a controlled setting. Many partial magnet displacements can be corrected with firm manual pressure. Devices with magnets that align with the field within their housing were not associated with any adverse events and do not require immobilization of the magnet during the scan. These may be valuable in patients with known or anticipated need for MRI.

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.

Objectives: To highlight superior semicircular canal dehiscence (SSCD) involving the superior petrosal sinus (SPS), and to propose a novel classification system for SPS associated SSCD with potential surgical implications. Study Design: Multicenter retrospective review. Setting: Three tertiary referral centers. Patients: All patients diagnosed with SPS associated SSCD (1/2000 to 8/2016). Radiographic findings and clinical symptoms were analyzed. Intervention: Surgical repair or observation. Main Outcome Measure: Radiographic findings and clinical symptoms were analyzed. Results: Thirty-three dehiscences (30 patients) involving the SPS were identified. The average age at the time of presentation was 52.5 years (median, 56.9; range, 4.9–75.3 yr), and 53.3% of patients were men. Three patients had bilateral SPS associated SSCD. The most common associated symptoms at presentation were episodic vertigo (63.6%), subjective hearing loss (60.6%), and aural fullness (57.6%). Four distinct types of dehiscence were identified: class Ia. SSCD involving a single dehiscence into an otherwise normal appearing SPS; class Ib. SSCD involving a single dehiscence into an apparent venous anomaly of the SPS; class IIa. SSCD involving two distinct dehiscences into the middle cranial fossa and the SPS; class IIb. SSCD involving a single confluent dehiscence into the middle cranial fossa and the SPS. Conclusions: SSCD involving the SPS represents a small but distinct subset of SSCD cases. This scenario can create a unique set of symptoms and surgical challenges when intervention is sought. Clinical findings and considerations for surgical intervention are provided to facilitate effective diagnosis and management.