### Date : 2024-06-24 12:47 ### Topic : Vestibular Neuritis #medicine #neurology #ENT ---- ### Vestibular Neuritis Overview **Vestibular neuritis** is an acute disorder of the vestibular system, specifically affecting the vestibular nerve, which leads to vertigo, dizziness, and imbalance. Unlike [[Labyrinthitis]], **vestibular neuritis does not typically involve hearing loss**. The exact cause is often unclear but is believed to be related to a viral infection. ### Etiology **Possible Causes:** - **Viral Infection:** Often suspected to be viral in origin, possibly following a respiratory or gastrointestinal infection. - **Inflammation:** Inflammation of the vestibular nerve disrupts the transmission of sensory information related to balance and spatial orientation from the inner ear to the brain.  <Photo from: https://www.vestibularhealth.ca/blog/vestibular-neuritis>  <Photo from: https://www.osmosis.org/learn/Anatomy_of_the_vestibulocochlear_nerve_%28CN_VIII%29> ### Pathophysiology 1. **Infection or Inflammation:** - Viral infection or inflammation damages the vestibular nerve. - The superior vestibular nerve is most commonly affected, although the inferior nerve can also be involved. 2. **Disrupted Signal Transmission:** - The impaired vestibular nerve cannot properly transmit balance signals from the inner ear to the brain. - This leads to a mismatch of information between the affected and unaffected sides of the vestibular system. 3. **Resultant Symptoms:** - The brain receives conflicting signals about the body's position and movement, causing vertigo, imbalance, and dizziness. ### Clinical Features **Symptoms:** - **Acute Onset of Vertigo:** Sudden, severe spinning sensation that can last for days. - **Dizziness:** Persistent feeling of unsteadiness or lightheadedness. - **Nausea and Vomiting:** Often accompany the vertigo due to the intensity of the sensation. - **Imbalance:** Difficulty maintaining balance, particularly when standing or walking. - **Nystagmus:** Involuntary, rhythmic eye movements usually observed during the acute phase. - **Absence of Hearing Loss:** Unlike labyrinthitis, vestibular neuritis typically does not affect hearing. ### Diagnosis **Clinical Evaluation:** - **History:** Sudden onset of vertigo, usually following a viral illness. - **Physical Examination:** Observing nystagmus and assessing balance and coordination. **Diagnostic Tests:** - **Head Thrust Test:** Positive head thrust test indicates a vestibular deficit. The patient’s eyes will make corrective saccades when the head is rapidly turned to the affected side. - **Electronystagmography (ENG) or Videonystagmography (VNG):** Assessing eye movements to diagnose vestibular disorders. - **[[Caloric Testing]]:** Evaluating the function of the vestibular system by irrigating the ears with warm or cold water and observing eye movements. **Exclusion of Other Causes:** - **MRI or CT Scan:** Rule out central causes of vertigo such as stroke or tumors. - **Audiometry:** Confirm no hearing loss to differentiate from labyrinthitis. ### Example Case Study **Patient Profile:** - **Name:** Jee Hoon Ju - **Age:** 50 - **Occupation:** Office Worker **Medical History:** - Recent upper respiratory infection. - Sudden onset of severe vertigo, nausea, and imbalance. **Clinical Evaluation:** - **Head Thrust Test:** Positive on the right side, indicating a right vestibular deficit. - **Nystagmus:** Spontaneous horizontal nystagmus observed. - **Audiometry:** Normal hearing levels. **Diagnosis:** Based on clinical presentation and test results, Jee Hoon Ju is diagnosed with right-sided vestibular neuritis. ### Management 1. **Symptomatic Treatment:** - **Vestibular Suppressants:** Medications such as meclizine, dimenhydrinate, or diazepam to reduce vertigo and nausea during the acute phase. - **Antiemetics:** To control nausea and vomiting (e.g., ondansetron, promethazine). 2. **Vestibular Rehabilitation Therapy (VRT):** - **Exercises:** Designed to promote central compensation and improve balance and coordination. - **Gaze Stabilization:** Exercises to help the brain adapt to the loss of vestibular function. - **Balance Training:** Exercises to enhance proprioception and stability. 3. **Recovery Phase:** - **Gradual Improvement:** Symptoms typically improve over several weeks as the brain compensates for the loss of vestibular input. - **Activity Encouragement:** Gradual return to normal activities to promote compensation and recovery. ### Prognosis - **Acute Phase:** Intense symptoms lasting a few days to weeks. - **Recovery:** Most patients experience significant improvement within several weeks to months. - **Long-Term:** Some individuals may have residual imbalance or dizziness, but these can often be managed with continued vestibular rehabilitation. ### Conclusion Vestibular neuritis is an acute vestibular disorder characterized by sudden onset vertigo, dizziness, and imbalance, often following a viral infection. Diagnosis is primarily clinical, supported by tests like the head thrust test and exclusion of other causes. Management focuses on symptomatic relief and vestibular rehabilitation to promote recovery and compensate for vestibular loss. Understanding the pathophysiology and effective management strategies can help alleviate symptoms and improve outcomes for patients with vestibular neuritis.