Dizziness handicap and clinical characteristics of posterior and lateral canal BPPV.

PURPOSE: Benign paroxysmal positional vertigo (BPPV) is diagnosed and divided into subtypes based on positioning vertigo and nystagmus. Whether these subtypes entail any significant differences in patient-reported symptoms; is yet not known. Such differences may have clinical and therapeutic consequences. Our aim was to assess dizziness handicap and clinical characteristics of posterior and lateral canal BPPV. METHODS: This prospective observational multicentre study analysed consecutive patients with BPPV, confirmed by standardized procedures including videonystagmography under diagnostic manoeuvres in a biaxial rotational chair. Patients were screened for other neurological and otological disorders. OUTCOMES: Dizziness handicap inventory (DHI), posterior vs. lateral canal involvement. FACTORS: age, gender, positional nystagmus intensity (maximum slow-phase velocity), symptom duration, 25-hydroxyvitamin D-level and traumatic aetiology. RESULTS: 132 patients aged 27-90 (mean 57, SD 13) years were included. Higher DHI scores were associated with lateral canal BPPV [95% CI (1.59-13.95), p = 0.01] and female gender [95% CI (0.74-15.52), p = 0.03]. Lateral canal BPPV was associated with longer symptom duration [OR 1.10, CI (1.03-1.17), p = 0.01] and lower 25-hydroxyvitamin D-levels [OR 0.80, CI (0.67-0.95), p = 0.03]. There was no correlation between DHI scores and nystagmus intensity. CONCLUSIONS: This study suggests that patients with lateral canal BPPV have increased patient-perceived disability, lower vitamin D-levels and longer duration of symptoms. This subtype might therefore require closer follow-up. Patient-perceived disability is not related to positional nystagmus intensity.

Insertion Depth in Cochlear Implantation and Outcome in Residual Hearing and Vestibular Function.

OBJECTIVES: It has long been known that cochlear implantation may cause loss of residual hearing and vestibular function. Different insertion depths may cause varying degrees of intracochlear trauma in the apical region of the cochlea. The present study investigated the correlation between the insertion depth and postoperative loss of residual hearing and vestibular function. DESIGN: Thirty-nine adults underwent unilateral cochlear implantation. One group received a Med-El +Flex electrode array (24 mm; n = 4), 1 group received a Med-El +Flex electrode array (28 mm; n = 18), and 1 group received a Med-El +Flex electrode array (31.5 mm; n = 17). Residual hearing, cervical vestibular-evoked myogenic potentials, videonystagmography, and subjective visual vertical/horizontal were explored before and after surgery. The electrode insertion depth and scalar position were examined with high-resolution rotational tomography after implantation in 29 subjects. RESULTS: There was no observed relationship between the angular insertion depth (405° to 708°) and loss of low-frequency pure-tone average. Frequency-specific analysis revealed a weak relationship between the angular insertion depth and loss of hearing at 250 Hz (R= 0.20; p = 0.02). There was no statistically significant difference in the residual hearing and vestibular function between the +Flex and the +Flex electrode array. Eight percent of the cases had vertigo after surgery. The electrode arrays were positioned inside the scala tympani and not scala vestibuli in all subjects. In 18% of the cases, the +Flex electrode array was not fully inserted. CONCLUSIONS: The final outcome in residual hearing correlates very weakly with the angular insertion depth for depths above 405°. Postoperative loss of vestibular function did not correlate with the angular insertion depth or age at implantation. The surgical protocol used in this study seems to minimize the risk of postoperative vertigo symptoms.

Deep round window insertion versus standard approach in cochlear implant surgery.

The aim of this study was to compare the outcomes of vestibular tests and the residual hearing of patients who have undergone full insertion cochlear implant surgery using the round window approach with a hearing preservation protocol (RW-HP) or the standard cochleostomy approach (SCA) without hearing preservation. A prospective study of 34 adults who underwent unilateral cochlear implantation was carried out. One group was operated using the RW-HP (n = 17) approach with Med-El +Flex(SOFT) electrode array with full insertion, while the control group underwent a more conventional SCA surgery (n = 17) with shorter perimodiolar electrodes. Assessments of residual hearing, cervical vestibular-evoked myogenic potentials (cVEMP), videonystagmography, subjective visual vertical/horizontal (SVH/SVV) were performed before and after surgery. There was a significantly (p < 0.05) greater number of subjects who exhibited complete or partial hearing preservation in the deep insertion RW-HP group (9/17) compared to the SCA group (2/15). A higher degree of vestibular loss but a lower degree of vertigo symptoms could be seen in the RW-HP group, but the differences were not statistically significant. It is possible to preserve residual hearing to a certain extent also with deep insertion. Full insertion with hearing preservation was less harmful to residual hearing particularly at 125 Hz (p < 0.05), than was the standard cochleostomy approach.

Scalar position in cochlear implant surgery and outcome in residual hearing and the vestibular system.

OBJECTIVE: To evaluate the effect of the intracochlear electrode position on the residual hearing and VNG- and cVEMP responses. DESIGN: Prospective pilot study. STUDY SAMPLE: Thirteen adult patients who underwent unilateral cochlear implant surgery were examined with high-resolution rotational tomography after cochlear implantation. All subjects were also tested with VNG, and 12 of the subjects were tested with cVEMP and audiometry before and after surgery. RESULTS: We found that although the electrode was originally planned to be positioned inside the scala tympani, only 8 of 13 had full insertion into the scala tympani. Loss of cVEMP response occurred to the same extent in the group with full scala tympani positioning and the group with scala vestibuli involvement. There was a non-significant difference in the loss of caloric response and residual hearing between the two groups. Interscalar dislocation of the electrode inside the cochlea was observed in two patients. A higher loss of residual hearing could be seen in the group with electrode dislocation between the scalae. CONCLUSIONS: Our findings indicate that intracochlear electrode dislocation is a possible cause to loss of residual hearing during cochlear implantation but cannot be the sole cause of postoperative vestibular loss.

The Risk of Benign Paroxysmal Positional Vertigo After Head Trauma.

OBJECTIVES: Head trauma may cause dislodgement of otoconia and development of benign paroxysmal positional vertigo (BPPV). The risk of developing BPPV is expected to be highest shortly after the trauma, then decrease and approach the risk seen in the general population. The aim of this study was to estimate the risk-time curve of BPPV development after head trauma. STUDY DESIGN: Prospective observational study. METHODS: Patients with minimal, mild, or moderate head trauma treated at the Department of Neurosurgery or the Department of Orthopedic Emergency at Oslo University Hospital, were interviewed and examined for BPPV using the Dix-Hallpike and supine roll maneuvers. BPPV was diagnosed according to the International diagnostic criteria of the Bárány Society. Telephone interviews were conducted at 2, 6, and 12 weeks after the first examination. RESULTS: Out of 117 patients, 21% developed traumatic BPPV within 3 months after the trauma. The corresponding numbers were 12% with minimal trauma, 24% with mild, and 40% with moderate trauma. The difference in prevalence between the groups was significant (P = .018). During the first 4 weeks after the trauma, it was observed 20, 3, 0, and 1 BPPV onsets, respectively. No BPPV cases were seen for the remainder of the 3-month follow-up. CONCLUSION: The risk of developing BPPV after minimal-to-moderate head trauma is considerable and related to trauma severity. Most cases occur within few days after the trauma, but any BPPV occurring within the first 2 weeks after head trauma are likely due to the traumatic event. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:443-448, 2022.

Treatment of horizontal canal BPPV-a randomized sham-controlled trial comparing two therapeutic maneuvers of different speeds.

OBJECTIVES: To compare the effect of a high-speed barbecue maneuver with the modified Lempert maneuver and sham in patients with benign paroxysmal positional vertigo (BPPV) of the horizontal canal. METHODS: Randomized sham-controlled, single blinded multicenter clinical trial in two university hospitals investigating consecutive patients with horizontal canal BPPV.Patients were randomly assigned to high-speed barbecue (HSB), modified Lempert maneuver (ML), or sham maneuver (SM). All treatments were performed in a biaxial rotational chair with weekly follow-up to a maximum of three treatment sessions. The final follow-up was 3 months after the last treatment. RESULTS: Primary outcome: 2-week recovery rate per protocol. Secondary outcome: Cumulative recovery rate and Dizziness Handicap Inventory (DHI) scores after 3 months per protocol (HSB and ML) and intention to treat (all groups).Fifty-four patients were analyzed after 2 weeks (HSB = 17; ML = 20; SM = 17). Two-week recovery rate was 14/17 after HSB, 11/20 after ML, and 4/17 after SM, with significantly better recovery in HSB [OR 15.17, 95% CI (1.85, 124.63), P = .001] using sham as base level. Recovery rate after 3 months was 15/17 after HSB and 15/19 after ML. Cumulative recovery rate showed no significant differences between the two treatment groups [95% CI (0.30, 13.14), P = .46] in cure rate DHI [95% CI (-16.56, 15.02), P = .92]. No unexpected adverse events were observed. CONCLUSION: Velocity change in horizontal canal BPPV treatment gives a faster initial recovery. Rapid recovery could reduce the disease burden. TRIAL REGISTRATION: Clinicaltrials.gov. Identifier: NCT01905800. LEVEL OF EVIDENCE: 1b.

Prevalence and Characteristics of Positional Nystagmus in Normal Subjects.

OBJECTIVE: In clinical practice, patients are often referred due to a finding of positional nystagmus that does not always appear to correlate with clinical symptoms of benign paroxysmal positional vertigo. To know when to consider nystagmus to be of clinical relevance, it is necessary to know the prevalence and characteristics of positional nystagmus in a healthy population. STUDY DESIGN: Case series of 75 healthy subjects. SETTING: Two tertiary referral centers in Norway. SUBJECTS AND METHODS: Seventy-five adult subjects aged 40 ± 13 years (mean ± SD; range, 21-87) without a history of vertigo or balance disorder were included from 2013 to 2015. The subjects underwent 6 different standardized positional tests in a repositioning chair. Videonystagmography was used to record eye movements. Of 1350 recordings, 1329 were included and analyzed. RESULTS: Positional nystagmus was detected in 88% of the subjects. The most common finding was nystagmus in the Dix-Hallpike position, which occurred in 55% of the subjects. The 95th percentile of the maximum slow-phase velocity for each subject was found to be 5.06° per second (n = 54) in the horizontal plane and 6.48° per second (n = 48) in the vertical plane. CONCLUSION: Positional nystagmus is a common finding in normal subjects and occurred in 88% of the healthy subjects in the present study. Horizontal direction-changing apogeotropic or geotropic nystagmus may occur in asymptomatic subjects. However, nystagmus that is of the paroxysmal type or has a slow-phase velocity greater than approximately 5° per second in the horizontal plane or 6.5° per second in the vertical plane should be considered outside the 95th percentile.