Case Report: Isolated Idiopathic Saccular Dysfunction

Advances in vestibular testing have now allowed us to test each semicircular canal as well as the utricle and saccule, independently. This has led to the discovery of new patterns of vestibular dysfunction that were once impossible to evaluate. This report describes the case of a 20-year-old woman with a 2-month history of recurrent dizziness. She had a complete audiovestibular assessment. The only abnormality observed was the absence of a cervical vestibular-evoked myogenic potential response for the right side, hence an isolated saccular dysfunction. In conclusion, isolated otolithic dysfunction is probably an overlooked and neglected clinical presentation. Its true incidence is unknown, and further research is needed to understand this clinical entity.

Peripheral Vestibular Dysfunction Is a Common Occurrence in Children With Non-syndromic and Syndromic Genetic Hearing Loss

Hearing loss (HL) is the most common sensory deficit in humans and is frequently accompanied by peripheral vestibular loss (PVL). While often overlooked, PVL is an important sensory dysfunction that may impair development of motor milestones in children and can have a significant negative impact on quality of life. In addition, many animal and in vitro models of deafness use vestibular hair cells as a proxy to study cochlear hair cells. The extent of vestibular end organ dysfunction associated with genetic pediatric hearing loss is not well-understood. We studied children with a known genetic cause of hearing loss who underwent routine preoperative vestibular testing prior to cochlear implantation between June 2014 and July 2020. Vestibular testing included videonystagmography, rotary chair, video head impulse testing, and/or vestibular evoked myogenic potentials. Etiology of HL was determined through history, physical examination, imaging, laboratory testing, and/or genetic testing. Forty-four children (21 female/23 male) met inclusion criteria; 24 had genetic non-syndromic and 20 had genetic syndromic forms of HL. Mean age at the time of testing was 2.8 ± 3.8 years (range 7 months−17 years). The most common cause of non-syndromic HL was due to mutations in GJB2 (n = 13) followed by MYO15A (3), MYO6 (2), POU3F4 (2), TMPRSS3 (1), CDH23 (1), TMC1 (1), and ESRRB (1). The most common forms of syndromic HL were Usher syndrome (4) and Waardenburg (4), followed by SCID/reticular dysgenesis (3), CHARGE (2), CAPOS (1), Coffin-Siris (1), Jervell and Lange-Nielsen (1), Noonan (1), peroxisome biogenesis disorder (1), Perrault (1), and Trisomy 21 (1). Overall, 23 patients (52%) had PVL. A larger proportion of children with syndromic forms of HL had PVL (12/20, 60%) compared with children with genetic non-syndromic HL (11/24, 46%), though without statistical significant (p = 0.3). The occurrence of PVL varied by affected gene. In conclusion, PVL is a common finding in children with syndromic and non-syndromic genetic HL undergoing vestibular evaluation prior to cochlear implantation. Improved understanding of the molecular physiology of vestibular hair cell dysfunction is important for clinical care as well as research involving vestibular hair cells in model organisms and in vitro models.

Acute vertigo in the ENT emergency

Summary Introduction: Acute vertigo ranks among the common reasons for visiting the emergency department. The aim of this study was to evaluate the rate of peripheral vestibular syndrome (PVS) in patients with acute vertigo examined at the ENT emergency department and to compare the agreement of physical ENT examination with video-assisted vestibular testing. Methods: Patients eamined at the ENT emergency department from January to December 2019 were evaluated retrospectively. The patients who underwent basic ENT examination without video-assisted vestibular testing form group A. The patients who underwent basic ENT examination which was followed by video head impulse test (vHIT) and videonystagmography in the next four days form group B. Results: A total of 117 patients with acute vertigo were included in group A, PVS was found in 31 patients (27%). In total, 50 patients were included in group B; PVS was found in 15 patients (30%), vestibular neuronitis was dia­gnosed most often (10 patients). The difference in the dia­gnosis of PVS by basic ENT examination (27 patients, 54%) and by video-assisted vestibular testing (15 patients, 30%) was statistically significant (P = 0.0030). The gain of the lateral (P = 0.0101) and superior (P = 0.0043) semicircular canal proved to be statistically significant, while vHIT was lower in PVS in comparison to other causes of vertigo. Conclusion: After basic ENT examination, PVS as a cause of acute vertigo was dia­gnosed in 27%. Video-assisted vestibular testing proved a statistically significant lower incidence of PVS in comparison to basic ENT examination. Accessibility of video- -assisted vestibular testing in the emergency department might allow for higher accuracy in the dia­gnosis of acute vertigo. Key words acute vertigo – vestibular function tests – video head impulse test – videonystagmography

THE UTILITY OF A MULTIDIRECTIONAL SUBMAXIMAL EXERTIONAL STEP AS PART OF AN EXERTIONAL REHABILITATION PROTOCOL AFTER CONCUSSION

Background: This study aimed to identify whether a 5 Step Exertional Rehabilitation Protocol including a submaximal multi-directional stage (Step 5) has clinical utility for functional activity and sport clearance. Exertional Rehabilitation (EP) is a graded protocol of aerobic exercise ranging from light linear exertion (Step 1) to submaximal linear exertion (Step 4)1,2. In our 5 Step Protocol, Step 4 is followed by standardized multi-directional functional movements at high intensity intervals (Step 5) to rule out ongoing exertional intolerance. Hypothesis/Purpose: We aim to investigate if Step 5 testing demonstrates statistical evidence for its use in determining concussion recovery timelines and its diagnostic usefulness. Methods: This retrospective-chart review analyzed 60 Step 5 EP test attempts in post-concussion patients, ages 21 or younger, between Jun2019-Jun2020. Tolerance was determined by a concussion specialist who evaluated for the onset of signs/symptoms by surveying the patient throughout exercise and autonomic assessment with cardiac monitoring and pre/post orthostatic testing. Pre/Post exertion King-Devic (K-D) and vestibular testing on Force Plate were completed following Balance Error Scoring System positions. A positive change in K-D was defined as a ≥2 second delay in score on two of three reading cards from the pre-exertion testing. A positive change in vestibular testing was defined as a ≥0.2deg/sec change in the composite balance score from the pre-exertion testing. Results: The total number of failed Step 5 attempts was 21.7%. Of the failed attempts, 38.5% demonstrated dysautonomia, 92.35% had symptoms, and 30.8% demonstrated both dysautonomia and symptoms. Force Plate balance scores significantly worsened in failed attempts 15.4% of the time while passed attempts only 2.1% of the time. K-D scores did not show a statistically significant difference although failed attempts did have slightly worsened scores. Conclusion: Formal Step 5 testing is a useful diagnostic tool for understanding recovery stage, activity tolerance, and sport clearance. Autonomic, visual, and vestibular testing can be useful as objective markers of test tolerance. Tables/Figures: [Figure: see text][Figure: see text] Citations: 1) Leddy JJ, Haider MN, Ellis MJ, Mannix R, Darling SR, Freitas MS, Suffoletto HN, Leiter J, Cordingley DM, Willer B. Early Subthreshold Aerobic Exercise for Sport-Related Concussion: A Randomized Clinical Trial. JAMA Pediatr. 2019 Apr 1;173(4):319-325. 2) Gagnon etal. Another look at active rehabilitation for slow-to-recover sport-related concussion in children and adolescents: further evidence to support its effectiveness. BJSM, 2013.

Cochlear Meniere's: A Distinct Clinical Entity With Isolated Cochlear Hydrops on High-Resolution MRI?

Objective: Describe the clinical characteristics of patients with isolated cochlear endolymphatic hydrops (EH).Study design: Clinical case series.Setting: Tertiary Neurotology referral clinic.Patients: All subjects presenting to a University Neurotology clinic during a 1-year period from July 2015 until August 2016 who had isolated cochlear EH on MRI. Patients with a history of temporal bone surgery prior to the MRI were excluded.Intervention: High-resolution delayed-intravenous contrast MRI.Main outcome measures: Audiometric and vestibular testing, clinical history analysis.Results: 10 subjects demonstrated isolated, unilateral cochlear hydrops on MRI. None of these patients met the criteria for Meniere's disease. Mean age of the group was 66.4 years and most were males (70%). Unilateral aural fullness (70%), tinnitus (80%), and hearing loss (90%) were frequently observed. Only one patient presented with unsteadiness (10%) and one patient had a single isolated spell of positional vertigo 1 month prior to the MRI (10%) but no further vertigo spells in the 4 years following the MRI. The mean PTA was 37.8 dB which was significantly decreased from the non-affected ear with PTA of 17.9 (p < 0.001). One patient developed vertiginous spells and unsteadiness 4 years after initial presentation and a repeat MRI revealed progression to utricular, saccular and cochlear hydrops. Vestibular testing was obtained in five patients with one patient presenting with 50% caloric paresis and all others normal. The most common treatment tried was acetazolamide in seven patients with 86% reporting subjective clinical improvement. Two out of the 10 patients had a history of migraine (20%).Conclusions: Patients with MRI exhibiting isolated cochlear EH present with predominantly auditory symptoms: mild to moderate low-frequency hearing loss, aural fullness, tinnitus without significant vertigo. Isolated cochlear hydrops is more common in males, average age in mid-60's and there is a low comorbidity of migraine headaches. This contrasts significantly with patients with isolated saccular hydrops on MRI from our prior studies. We believe that isolated cochlear EH with hearing loss but no vertigo is distinct from Meniere's disease or its variant delayed endolymphatic hydrops. We propose that cochlear Meniere's disease represents a distinct clinical entity that could be a variant of Meniere's disease.