Reference ranges and stability of auditory and vestibular measures in a comprehensive assessment battery for traumatic brain injury.

BACKGROUND: Audiology clinics have many tools available to evaluate auditory and vestibular complaints. However, many tools lack established normative ranges across the life span. We conducted this study to establish reference ranges across the life span for audiology/vestibular measures commonly used to evaluate patients with traumatic brain injury. MATERIALS AND METHODS: In this repeated measures study, 75 adults, ages 18-65 years, without a history of traumatic brain injury, underwent robust auditory/vestibular evaluations three times over six months, including rotational chair, videonystagmography, computerized dynamic posturography, vestibular evoked myogenic potentials, and retinal fundoscopy. RESULTS: Age effect was notable for transient evoked otoacoustic emissions, pure-tone audiometry, auditory brainstem response, auditory middle latency response, and auditory-steady state response at 4000 hertz (Hz). Older participants (50-65 years) were more likely to have delayed latency horizontal saccades, positional nystagmus, slowed lower-extremity motor control responses, and delayed latency ocular vestibular evoked myogenic potentials. Low to mid-frequency horizontal (0.003-4 Hz) and mid-frequency vertical (1-3 Hz) vestibulo-ocular reflex, otolith-mediated reflexes, dynamic visual acuity and balance measures were generally not influenced by age. Females had larger static subjective visual testing offset angles, longer cervical vestibular evoked myogenic potential P1 latency, faster velocity horizontal saccades, and quicker motor control latency for large backward translations than age-matched males. CONCLUSION: These reference ranges can be used to discern impairment within the auditory and vestibular pathway following traumatic brain injury in young to middle-aged adults. ID: TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT01925963.

Sleep assessment in a randomized trial of hyperbaric oxygen in U.S. service members with post concussive mild traumatic brain injury compared to normal controls.

STUDY OBJECTIVE: In this exploratory, double-blind, longitudinal sham-controlled trial of hyperbaric oxygen (HBO2) for military personnel with post concussive mild traumatic brain injury (mTBI), self-reports and objective measures of sleep-wake disturbances were assessed and compared to normals. METHODS: Self-reports consisting of Pittsburg Sleep Quality Index (PSQI), sleep diary, screening for obstructive sleep apnea (OSA) risk, restless legs syndrome (RLS), cataplexy, and objective actigraphic measures of sleep-wake were obtained on 71 military personnel with mTBI [baseline, 13 weeks and six months post-randomization (post-intervention)], of which 35 met post-traumatic stress disorder (PTSD) criteria, and 75 healthy volunteers (baseline). Baseline between-group and follow-up changes from baseline overall and within subgroups were evaluated. Mild TBI was defined as consisting of head injury associated loss of consciousness (<24 h), post-traumatic amnesia, and neurological deficits. RESULTS: Sleep quality by self-reports was markedly degraded in the mTBI group at baseline compared to a normative cohort; insomnia 87.3 versus 2.8%, OSA risk 70% versus 1.3%, RLS 32.4% versus and 2.7%. (all p-values <0.001), but actigraphy measures did not differentiate between groups. HBO2 compared to sham treatment improved self-reports of PSQI sleep measures, reports (five out of eight at 13-weeks and two out of eight at six-months). However, other sleep-wake measures were not different. CONCLUSIONS: Perceived sleep quality was markedly disrupted in mTBI military personnel and sleep-wake disturbances were prevalent compared to a normative cohort. HBO2 relative to sham improved some measures of sleep quality on the PSQI, but other measures of sleep were not significantly different.