Snapshot A 34-year-old woman presents to the emergency department with acute onset and sustained vertigo. She said her symptoms occured "out of the blue" and is accompanied by severe nausea and gait instability. She feels the room is spinning and denies experiencing lightheadedness or palpitations. One week prior to presentation she developed a viral upper respiratory infection. She has no past medical history and her family history is unremarkable. On physical examination, she has horizontal nystagmus that is suppressed with visual fixation. She also has a positive head-thrust test. There is no hearing loss. She is started on prednisone and given ondansetron and meclizine for symptom improvement. Introduction Overview a viral or post-viral inflammation of the vestibular nerve resulting in peripheral vertigo Epidemiology Demographics men and women are affected equally 40-50 years of age Risk factors herpes simplex virus (HSV) infection (typically) other viral illnesses (e.g., adenovirus) ETIOLOGY Pathophysiology mechanism of injury unclear but believed to be due to an inflammatory response to the vestibular nerve Anatomy Organ inner ear Presentation Symptom acute onset severe vertigo nausea vomiting Physical exam nystagmus suppressed with visual fixation positive head thrust test rapid turning of the head towards the affected ear makes the patient unable to fixate on a distant object gait instability patient still has the ability to ambulate Imaging MRI brain with diffusion-weighted images indication only used to rule-out an alternative cause of vertigo when the clinical exam is not consistent with a peripheral vertigo Differential Cerebellar vascular event (infarction or hemorrhage) differentiating factors typically seen in older patients with vascular risk factors (e.g., hypertension, diabetes, smoking, and hyperlipidemia) nystagmus is not suppressed with visual fixation vertigo is continuous for many hours Wallenberg syndrome differentiating factors ipsilateral horners syndrome horseness and dysphagia pain and temperature sensation loss in the ipsilateral face and contralateral body Meniere disease differentiating factors ear fullness and sensorineural hearing loss Treatment Conservative & Lifestyle vestibular rehabilitation indication can lead to meaningful recovery in patients Medical & pharmacologic corticosteroids indication used as initial therapy symptomatic treatment indication used in the early days of vertigo for symptomatic improvement medications meclizine lorazepam ondansetron Complications Head injury from falls Prognosis Typically self-limiting