Do Patients Benefit From a Cochlear Implant When They Qualify Only in the Presence of Background Noise?

OBJECTIVE: To compare the difference in pre- to postoperative speech performance of patients qualifying for a cochlear implant (CI) in quiet, +10 dB signal-to-noise ratio (SNR), and +5 dB SNR. STUDY DESIGN: Retrospective. SETTING: Tertiary referral center. PATIENTS: Fifty-eight post-lingually deafened, unilateral CI recipients from three Groups were included: 1) those who met CI candidacy criteria with AzBio sentences in quiet, 2) in noise at +10 dB SNR but not in quiet, 3) and in noise at +5 dB SNR but not in quiet or +10 dB SNR. INTERVENTION: Unilateral CI. MAIN OUTCOME MEASURES: Pre- and 1 year postoperative speech recognition scores. RESULTS: Best-aided AzBio speech recognition of individuals in Group 1 improved significantly for all test conditions and improved significantly for Groups 2 and 3 in the +10 and +5 dB SNR test conditions postoperatively. When tested with their CI alone however, while AzBio speech recognition of individuals in Group 1 and Group 2 improved significantly in the quiet and +10 dB SNR conditions, speech recognition was not significantly changed postoperatively under any testing condition for individuals in Group 3. CONCLUSIONS: While individuals qualifying for a CI only in the +5 dB SNR condition may derive significant benefit from implantation in best aided conditions, speech understanding outcomes can be more variable thus warranting additional counseling before implantation and case-by-case consideration of listening needs and goals.

Canal conversion and reentry: a risk of Dix-Hallpike during canalith repositioning procedures.

OBJECTIVE: To determine the incidence, cause, and prevention of horizontal canal benign paroxysmal positional vertigo (H-BPPV) and reentry into the common crus during canalith repositioning procedures (CRPs). STUDY DESIGN: Prospective case series. SETTING: Academic tertiary referral center. PATIENTS: Forty-four patients with symptomatic posterior canalithiasis (P-BPPV) confirmed on Dix-Hallpike. INTERVENTION: Up to 5 CRP for initial P-BPPV and additional maneuvers for canal conversion or reentry in 1 session. MAIN OUTCOME MEASURES: Incidence and timing of onset of H-BPPV or common crus reentry and the outcome of treatment maneuvers. RESULTS: H-BPPV or reentry occurred during the Dix-Hallpike after a canal-clearing CRP and affected 16% (7/44) of subjects. Approximately 87% (7/8) of reentry or conversion events occurred after the very first CRP. Geotropic H-BPPV occurred in 9% (4/44) overall but in 13% (4/30) whose P-BPPV was resolved by a single CRP. All were cleared with H-BPPV maneuvers, 3 of 4 resolving with a single Gufoni maneuver. Approximately 9% (4/44) of patients developed reentry of particles into the common crus. It was treated by raising the patient to the upright position. By waiting 15 minutes after treatment of reentry, a final normal Dix-Hallpike was obtained without causing reentry into any canal in all patients. CONCLUSION: If the first CRP clears the posterior canal, there is an elevated risk of reentry or canal conversion if another Dix-Hallpike is performed immediately. These complications can be treated by additional maneuvers; if unfamiliar with these techniques, the risk can be reduced by waiting at least 15 minutes between repetitions of CRP.

Reliability of vestibular evoked myogenic potentials in healthy subjects.

OBJECTIVE: To analyze test-retest reliability of vestibular evoked myogenic potential (VEMP) responses with and without the use of electromyography (EMG) monitoring in people with normal audiovestibular function. PATIENTS: Twenty adult volunteers with no history of ear disease, normal otoscopic examination, normal pure-tone audiometry thresholds, and normal tympanograms. INTERVENTIONS: Prospective evaluation of VEMP responses with and without the use of EMG monitoring in 2 separate sessions 1 to 4 weeks apart. MAIN OUTCOME MEASURES: Threshold repeatability, p13 and n23 latency, p13-n23 interlatency, and interamplitude and interaural amplitude difference from the first and the second sessions were assessed via the intraclass correlation coefficient. RESULTS: Test-retest reliability of p13-n23 interamplitude was found to be excellent, and the reliability of threshold and latency was found to be fair to good (with the exception of poor reliability for p13 latency in the EMG monitoring condition). CONCLUSION: Overall, VEMP response parameters were found to have fair to good test-retest reliability. The intraclass correlation coefficient value for amplitude was found to be more reliable than latency, with the latency of n23 more reliable than the latency of p13. Clinicians should consider these findings when interpreting VEMP responses. Maintenance of symmetric head rotation with and without EMG monitoring produced reliably reproducible results, the VEMP amplitude being the best criteria.