Auditory Prognosis of Patients With Sudden Sensorineural Hearing Loss in Relation to the Presence of Acute Vestibular Syndrome: A Systematic Literature Review and Meta-Analysis.

OBJECTIVES: Hearing recovery following idiopathic sudden sensorineural hearing loss (ISSNHL) is influenced by various prognostic factors, and the presence of acute vestibular syndrome (AVS) may adversely impact auditory outcomes. Evaluating vestibular function in SSNHL patients could offer insights into predicting hearing recovery. This systematic review aims to assess whether the presence of AVS exacerbates the audiological prognosis of ISSNHL. DESIGN: A comprehensive systematic review was conducted using databases such as PubMed, Cochrane Library, EMBASE, and Scopus, encompassing articles published in the last decade. Included were retrospective and prospective case-control and cohort studies, as well as randomized clinical trials. Meta-analysis was performed based on the findings from these studies. RESULTS: Among 386 articles identified, six addressed the systematic review's question, all being retrospective studies. These articles collectively involved 393 patients for the meta-analysis. Vestibular function assessment methods varied widely, posing challenges for direct comparisons. The likelihood of unfavorable hearing outcomes was 2.29 times higher in patients with associated AVS. Hearing recovery was 3.22 times more likely to be worse in patients with altered cervical vestibular evoked myogenic potentials-air-conducted sound. Abnormal caloric test results showed no significant association with worse hearing prognosis, although patients with unaltered caloric tests demonstrated a significantly greater improvement in pure-tone audiometry. CONCLUSIONS: Hearing recovery from ISSNHL appears to be diminished in patients with associated AVS and abnormal vestibular test results.

Positional End-Point Nystagmus in Patients with Diagnosis of Acute Unilateral Vestibulopathy.

INTRODUCTION: Recently, end-point nystagmus, traditionally observed in an upright position, has been identified in the Dix-Hallpike position among healthy subjects, suggesting a physiological origin.However, its characteristics in individuals with vestibular hypofunction remain unexplored. OBJECTIVE: To elucidate the impact of vestibular hypofunction on the characteristics of positional end-point nystagmus. METHODS: Thirty-one patients diagnosed with acute unilateral vestibulopathy according to Bárány Society criteria were selected. A video head impulse test was conducted in all participants, followed by McClure and Dix-Hallpike maneuvers with and without gaze fixation, and with the initial position of the eye in the straight-ahead position or in the horizontal end-point position. Nystagmus direction, sense, latency, slow-phase velocity, and duration were recorded. The relationship between these characteristics and video head impulse test values was analyzed. RESULTS: Positional end-point nystagmus was observed in 92.6% of subjects with vestibular hypofunction, significantly more than in healthy individuals. Nystagmus direction varied depending on the performed positional test and on the vestibulo-ocular reflex gains. Gaze occlusion and the initial horizontal end-point position increased its frequency. CONCLUSION: Vestibular hypofunction influences the manifestation of positional end-point nystagmus. Recognizing this nystagmus can aid in resolving diagnostic uncertainties and preventing the misdiagnosis of benign paroxysmal positional vertigo in subjects with acute unilateral vestibulopathy.

Positional End-Point Nystagmus during Positional Testing: Prevalence, Characteristics and Differences with Benign Paroxysmal Positional Vertigo.

BACKGROUND: Some individuals present positional end-point nystagmus when the Dix-Hallpike tests are performed on them if they unintentionally look towards the examined ear. OBJECTIVE: To describe the prevalence and the characteristics of end-point nystagmus during positional testing in healthy subjects. METHODS: Sixty healthy subjects were included. Eight positional tests were performed on them, two Pagnini-McClure tests and six Dix-Hallpike tests, while keeping the eyes in different positions; one on each side. Two independent observers filled in a questionnaire about the presence of positional nystagmus, its latency, duration, direction, and sense. RESULTS AND CONCLUSIONS: Of the subjects, 65% showed positional end-point nystagmus. This nystagmus had a short latency and last for as long as the head is maintained in the test position. They can show any direction or sense, but the most common are torsional clockwise in left tests and anticlockwise in right tests. Unlike BPPV, this nystagmus did not appear with the eyes in the straight-ahead position, it is asymptomatic, and its intensity does not decline.

Identifying Training, Diagnostic and Therapeutic Needs From a Comparison in the Distribution of Vestibular Disorders in Primary Care and in a Neurotology Unit.

Introduction: Several epidemiological studies in Neurotology have been previously carried out in the general population. This approach is useful for learning about the most common disorders in clinical population, but it may fail when one is trying to help professionals to guide their training, to optimize their resources and to decide on the highest-priority research objectives. Objective: To identify which of the neurotological diseases are most common in two different populations, those who attended a consultation in the Neurotology Unit of a tertiary level hospital and those who did so in Primary Care in order to infer which of them requires more attention in each context and their specific needs. Methods: All the diagnoses made in Hospital Care between October 15, 2017 and October 14, 2018 were reviewed. These diagnoses were coded and classified into syndromes and diseases. Later, the proportions of each category were compared with the proportions of the neurotological diagnoses made in five Primary Care centers over the same period of time. Results: BPPV is the most common cause of vestibular symptoms in both contexts. Vestibular migraine, ischemic vestibular symptoms, orthostatic hypotension and side effects of drugs are common in Primary Care, whereas Ménière's disease and undifferentiated episodic vestibular syndrome are common in specialized centers. Conclusion: The proportion of diagnoses in neurotologic patients is different in the general population and in the specialized center population, and therefore they have different needs. Primary Care professionals would benefit from training on maneuvers for repositioning otoliths, the treatment of headache, the identification of cardiovascular risk factors, the orthostatic hypotension and the side effects of the most commonly used drugs. The professionals who work in specialized centers need strategies for dealing with cases of BPPV associated to other vestibular diseases and refractory cases and their research should focus on the development of new diagnostic tools for the diagnosis of undifferentiated episodic vestibular syndrome and new therapeutic options for Ménière's disease.