Dynamic posturography after computerized vestibular retraining for stable unilateral vestibular deficits.

BACKGROUND: Balance deficits increase the risk of falls and compromise quality of life. Current treatment modalities do not resolve symptoms for many patients. AIMS/OBJECTIVES: To measure changes in objective posturography after a computerized vestibular retraining therapy protocol. MATERIALS AND METHODS: This was a single-arm interventional study of individuals with a stable unilateral vestibular deficit present for greater than six months. Participants underwent 12 twice-weekly sessions of computerized vestibular retraining therapy. Objective response was measured by the Sensory Organization Test and questionnaires were administered to measure subjective changes. RESULTS: We enrolled 13 participants (5 females and 8 males) with a median age of 51 years (range 18 to 67). After retraining, the Sensory Organization Test composite score improved by 8.8 (95% CI 0.6 to 19.1) and this correlated with improvement in the Falls Efficacy Scale-International questionnaire (rs -0.6472; 95% CI -0.8872 to - 0.1316). Participants with moderate-to-severe disability at baseline (n = 7) demonstrated greater improvement in the composite score (14.6; 95% CI 7.0 to 36.9). CONCLUSIONS AND SIGNIFICANCE: Computerized vestibular retraining therapy for stable unilateral vestibular deficits is associated with improvement in dynamic balance performance. Posturography improvements correlated with a reduction in perceived fall risk. Trial Registration Information Clinicaltrials.gov registration NCT04875013; 04/27/2021.

Durable improvement in participant-reported measures of disability and objective posturography after computerized vestibular retraining.

BACKGROUND: Unilateral vestibular deficits are associated with postural instability and loss of quality of life. Common treatments frequently fail to achieve satisfactory outcomes. OBJECTIVE: To assess the durability of changes in participant-reported disability and objective posturography after computerized vestibular retraining. METHODS: This was a single-group study. Individuals with persistent symptoms of an objectively determined unilateral vestibular deficit completed questionnaires and posturography assessments before and after twelve sessions of computerized retraining, and 4-6 months and 10-12 months after treatment. RESULTS: 13 participants completed the post-treatment assessments; 9 completed the follow up. Mean improvements in perceived disability at 4-6 months after retraining were: DHI 14.3 points (95% confidence interval 4.0 to 24.5), ABC scale 14.9 points (4.3 to 25.6), FES-I 11.6 points (-3.2 to 26.5).The SOT composite score increased by 11.4 points (95% CI 1.9 to 20.9; p = 0.0175) immediately after treatment, 8.9 points (-2.9 to 20.7; p = 0.1528) at 4-6 months, and 10.6 points (2.2 to 19.0; p = 0.0162) after 10-12 months. At the 10-12 month time point, the areas of the functional stability region increased significantly for both endpoint excursion (p = 0.0086) and maximum excursion (p = 0.0025). CONCLUSION: Computerized vestibular retraining was associated with improved participant reported disability and objective measures of postural stability.

Patient-Reported Disability After Computerized Posturographic Vestibular Retraining for Stable Unilateral Vestibular Deficit.

Importance: Individuals with persistent unilateral vestibular deficits experience loss of quality of life and increased risk of falling, and they have few well-supported options for effective treatment. Objectives: To evaluate whether vestibular retraining using computerized dynamic posturography is associated with reduced participant-reported disability for patients with an objectively assessed unilateral peripheral vestibular deficit and to assess the feasibility of conducting a randomized clinical trial of vestibular retraining using computerized dynamic posturography. Design, Setting, and Participants: This single-group cohort study was conducted from April 29 to July 23, 2021, in a tertiary neurotology clinic among 13 individuals with a stable unilateral vestibular deficit present for more than 6 months, confirmed with videonystagmography and vestibular evoked myogenic potential testing. Statistical analysis was performed from July 7, 2021, to January 25, 2022. Interventions: Twelve twice-weekly sessions of posturography-assisted vestibular retraining with prescribed weight shifting tasks guided by an interactive display. Main Outcomes and Measures: Change in scores on the Dizziness Handicap Inventory (DHI), the Activities-Specific Balance Confidence (ABC) Scale, and the Falls Efficacy Scale-International (FES-I), which participants completed before and after retraining to measure their perception of their disability. They also completed posturography measurements. Secondary outcomes included tolerability of the intervention and rate of completion of the full protocol. Results: A total of 13 participants (8 men [62%]; median age, 51 years [range, 18-67 years]) were enrolled. All 13 participants completed the intervention and all follow-up. After treatment, the median changes in scores were -16 points (95% CI, -20 to 2) for the DHI, -9 (95% CI, -14 to 1) for the FES-I, and 11.9 (95% CI, 0-17.3) for the ABC Scale. Eight participants (62%) improved by greater than the minimum clinically important difference (MCID) for the DHI, whereas 4 (31%) exceeded the MCID for the ABC Scale, and 3 (23%) exceeded the MCID for the FES-I. Participants with moderate to severe disability at baseline (n = 7) had a larger magnitude of improvement in DHI scores than those with mild disability (n = 6) (-18 [95% CI, -78 to 2] vs -1 [95% CI, -8 to 16]). Six of the 7 patients (86%) with moderate to severe disability improved by greater than the MCID for DHI, wherease 4 of 7 patients (57%) improved by greater than the MCID for the ABC Scale, and 3 of 7 patients (43%) improved by greater than the MCID for the FES-I. Conclusions and Relevance: This cohort study suggests that computerized, dynamic posturography-assisted retraining was associated with clinically meaningful improvements in participant-reported disability among those with stable unilateral vestibular deficit and moderate to severe disability. Further studies should compare posturography-assisted vestibular retraining with conventional physical therapy rehabilitation techniques. Trial Registration: ClinicalTrials.gov Identifier: NCT04875013.

Normal values for cervical and ocular vestibular-evoked myogenic potentials using EMG scaling: effect of body position and electrode montage.

BACKGROUND: The clinical utility of cervical and ocular vestibular-evoked myogenic potential (cVEMP and oVEMP) is limited by variability of testing protocols and a dearth of normative data using contemporary methods for amplitude scaling. AIMS/OBJECTIVES: To investigate the effect of body position and electrode montage on VEMP responses and to establish normative values. MATERIAL AND METHODS: This is a repeated measures study of 44 healthy young adult subjects (22 men and 22 women). RESULTS: The highest response rate (99%) for cVEMP was achieved in the supine position with the head elevated and turned. For oVEMP, the highest response rate (90%) was achieved using nasal alar electrode montage with the subject in a sitting position. Scaled peak-to-peak amplitude was higher in males than in females for both cVEMP and oVEMP. CONCLUSION: Normative data for 44 young healthy adults was successfully collected for two body positions for cVEMP and two head positions and two electrode montages for oVEMP. SIGNIFICANCE: Our findings describe VEMP protocols that efficiently detect VEMP responses, and we provide normative VEMP response data for young healthy subjects. We describe a potential difference in response between males and females, which may be clinically important.

Medial canal fibrosis: surgical technique, results, and a proposed grading system.

OBJECTIVE: To report the hearing and surgical results in patients with medial canal fibrosis. To describe the surgical technique for removal of medial canal fibrosis and to propose a classification for grading postoperative surgical outcome and to correlate this with hearing results. SETTING: Tertiary university referral center. STUDY DESIGN: Retrospective case review. METHODS: Twenty-one patients with mature medial canal fibrosis underwent a total of 26 operations at our institution from February 1994 to June 2003. Four patients underwent surgery for bilateral disease and another had a second operation for recurrence. RESULTS: According to the proposed grading system, 10 (38.5%) of the 29 ears operated on achieved a Grade I result (normal self-cleaning ears) and three (11.5%) had recurrence (Grade III). One patient was found to have external ear canal cholesteatoma. Postoperatively, 15 ears demonstrated closure of the air-bone gap to within 10 dB or improvement on four-frequency average pure-tone audiogram to better than 25 dB. The mean preoperative air-bone gap was 28.7 dB compared with 12.5 dB postoperatively (p < 0.001). When hearing results were correlated with postoperative grade, 90.0% of the ears with a Grade I result had significant hearing improvement, 46.2% in patients with Grade II and 33.3% in patients with Grade III results. Four patients complained of temporomandibular joint pain postoperatively. CONCLUSION: Surgery remains the treatment of choice for mature medial canal fibrosis. With proper surgical technique and meticulous postoperative care, a patent and functioning external ear canal can be achieved in a majority of patients. Absence of recurrence does not equate with improved hearing thresholds.

Evaluation of the high-resolution speech coding strategy for the Clarion CII cochlear implant system.

Four postlinguistically deafened adults were implanted with the Clarion CII cochlear implant with the HiFocus II electrode in an evaluation of performance with a new speech coding strategy (high resolution) compared with current speech coding strategies (multiple pulsatile sampler, continuous interleaved sampling, and simultaneous analog stimulation). These strategies were implemented in the Platinum speech processor from Advanced Bionics Corporation (Sylmar, CA). Postoperatively, subjects were fitted with the traditional coding strategies and over the first month were allowed to determine their strategy of choice. This strategy was used to evaluate open-set speech recognition performance at 1 month and 3 months postfitting. At 3 months postfitting, subjects were reprogrammed with the high-resolution strategy. They returned for speech recognition testing at 1 month and 3 months postfitting with this strategy. Performance was significantly better with the high-resolution strategy for all four subjects, particularly when listening to speech in background noise. This finding was in agreement with their strong preference for the high-resolution strategy, and all four patients continue to use the high-resolution strategy.

Cochlear delivery of fibroblast growth factor 1 and its effects on apoptosis and cell cycling in noise-exposed guinea pig ears.

OBJECTIVES: Acidic fibroblast growth factor 1 (FGF-1) is a mitogen and antiapoptotic factor synthesized by cochlear neurons and transported to the organ of Corti. The objectives of this investigation were threefold: (1) to develop an animal model to study the cochlear effects of intratympanic delivery of FGF-1; (2) to determine the distribution, in the mature mammalian cochlea, of FGF-1 and the receptor, FGFR3, to which it binds with high affinity; and (3) to examine the effect of exogenous FGF-1 on cochlear apoptotic and cell-cycling markers in noise and non-noise-exposed guinea pigs ears. METHODS: Fifteen adult Hartley guinea pigs were divided into three groups. Group 1 animals (n = 5) underwent direct placement of FGF-1 in phosphate buffered saline (PBS) (20 pg/mL) soaked Gelfoam pledgets to the right round window membrane. Phosphate buffered saline-soaked Gelfoam pledgets were placed on the left round window membrane as a control. In group 2 animals (n = 5), surgical placement of either FGF-1 or PBS was followed by exposure to 120 dB of white noise for 2 hours. Group 3 animals (n = 5) were subjected to identical noise conditions prior to undergoing round window application of either FGF-1 or PBS. All groups were allowed to recover in a noise-controlled environment for 12 hours following surgery. Anti-FGF-1-stained Western blots and optical densitometry analyses were used to quantitate passage of FGF-1 into cochlear perilymph. Standard in situ immunohistochemical techniques were used to stain each cochlea for FGF-1 and FGFR3, apoptotic markers p53 and p21, Bcl-2, and the cell-cycling marker proliferating cell nuclear antigen (PCNA). Tissue sections were subjected to the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling technique (TUNEL) for apoptosis. RESULTS: Western blot and optical densitometry analyses of cochlear perilymph showed increased concentrations of FGF-1 in 10 of 14 experimental cochleas. Cochlear perilymph FGF-1 was consistently bound to heparan sulphate proteoglycan (HSPG). Immunoreactivity of both FGF-1 and FGFR3 was observed in spiral ganglion neurons, inner and outer hair cells, pillar cells, and Dieter and Hensen's cells. Specific FGF-1 immunostaining to the distal portion of the pars pectinata of the basilar membrane was noted in noise-exposed animals only. Bcl-2 and PCNA immunostaining was not detected in any group. There was no significant nuclear immunoreactivity to proapoptotic markers, p53 and p21, in any group. Semiquantitative analysis of TUNEL staining in block sections of all cochleas demonstrated a 340% increase in nuclear immunoreactivity of noise-exposed outer hair cells and organ of Corti cells. There was no difference between FGF-1 treated and control ears subjected to TUNEL staining. CONCLUSIONS: Exogenous FGF-1 crosses the round window membrane and is bound to HSPG in cochlear perilymph. The specific immunoreactivity of the pars pectinata to FGF-1 may represent a unique reservoir for cochlear FGF-1 in noise-exposed ears of the guinea pig. Noise induces apoptosis of organ of Corti cells as demonstrated with the TUNEL technique. PCNA, Bcl-2, p53, and p21 in noise-exposed and non-noise-exposed guinea pig cochleas are not affected by exogenous FGF-1. Noise-induced hair cell apoptosis appears to be independent of the p53 pathway. Lack of immunoreactivity to Bcl-2 supports the concept that the apoptotic mechanism is likely to involve C-Jun-N-terminal kinase- or caspase-dependent pathways. Exogenous FGF-1 does not alter apoptosis or cell cycling in the mature guinea pig cochlea within 12 hours of acute acoustic trauma.