Vertigo is a sensation of spinning or feeling that your surroundings are moving, even when you are still. It differs from general dizziness, which is lightheadedness or unsteadiness. This sensation often arises from issues within the inner ear, a complex system central to maintaining balance. An Ear, Nose, and Throat (ENT) specialist, also known as an otolaryngologist, is frequently consulted for evaluating balance disorders. Their expertise in the ear’s intricate structures makes them well-suited to identify the source of vertigo.
Gathering Initial Information
When a patient presents with vertigo, an ENT begins with a comprehensive medical history. This involves detailed questions about the dizziness’s nature (spinning, lightheadedness, or unsteadiness), onset, duration, and triggers. Associated symptoms like hearing changes (hearing loss or tinnitus), ear fullness, nausea, vomiting, or headaches are also discussed. This history helps the ENT understand the patient’s experience and guides subsequent diagnostic steps.
A physical examination follows, including inspecting the ears, nose, and throat. A neurological assessment checks coordination, reflexes, and eye movements. The ENT looks for nystagmus, involuntary, rapid eye movements, which indicate a balance system issue. This evaluation provides insights into whether the vertigo stems from a peripheral issue (inner ear) or a central issue (brain).
Specialized Vestibular and Hearing Assessments
To pinpoint the cause of vertigo, ENTs employ several specialized tests focusing on the vestibular system and hearing. These assessments provide objective data on how the inner ear and its brain connections are performing, offering a comprehensive understanding of the patient’s condition.
Videonystagmography (VNG) or Electronystagmography (ENG)
Videonystagmography (VNG) or Electronystagmography (ENG) record eye movements to assess inner ear and central motor function. Patients wear goggles tracking eye movements as they follow visual targets, move their head, or respond to temperature changes. Caloric irrigation involves introducing warm or cool air or water into the ear canal, stimulating inner ear balance canals and eliciting nystagmus. Observing these induced eye movements helps differentiate between peripheral vestibular issues and central nervous system problems.
Vestibular Evoked Myogenic Potentials (VEMP)
Vestibular Evoked Myogenic Potentials (VEMP) testing evaluates the function of inner ear organs called otoliths (saccule and utricle). These organs detect linear acceleration and head position. The VEMP test measures muscle responses, from the neck (cVEMP) or eye muscles (oVEMP), to sounds or vibrations, indicating the integrity of nerve pathways from these otolith organs.
Rotary Chair Test
The Rotary Chair Test assesses the inner ear’s response to rotational movements, providing information about both ears simultaneously. The patient sits in a computer-controlled chair that rotates at varying speeds, while eye movements are recorded. This test measures the vestibulo-ocular reflex (VOR), which helps maintain stable vision during head movements. Abnormalities in VOR gain, phase, or symmetry can indicate issues within the vestibular system or its central connections.
Posturography
Posturography measures a person’s ability to maintain balance while standing on a specialized platform. The platform can be static or dynamic, moving in different directions or speeds, and the test may be performed with eyes open or closed, with or without visual distractions. This test helps determine which sensory systems—vestibular, visual, or somatosensory—a person relies on most for balance and which might be contributing to their imbalance.
Hearing Tests
Hearing tests, such as audiometry, are routinely performed because inner ear structures for hearing are connected to those for balance. Conditions affecting one system often impact the other. Audiometry helps identify any hearing loss associated with vertigo, providing a complete picture of inner ear health.
Interpreting Findings and Diagnosis
After a thorough patient history, physical examination, and specialized tests, the ENT synthesizes all gathered information. This comprehensive approach confirms vertigo and determines its specific type and origin. The ENT looks for distinct patterns in test results, which often correspond to particular conditions affecting the balance system. For instance, certain VNG findings can point towards benign paroxysmal positional vertigo (BPPV), a common cause of vertigo due to dislodged inner ear crystals.
Identifying whether the problem originates in the peripheral vestibular system (inner ear) or the central nervous system (brain) is a primary goal. VNG, VEMP, and rotary chair results provide crucial data to distinguish these categories. If central nervous system causes or structural issues are suspected, further diagnostic imaging, such as an MRI or CT scan, might be ordered. These studies rule out conditions like tumors, stroke, or multiple sclerosis, which can also cause vertigo.
Based on the full evaluation, the ENT diagnoses and discusses management strategies with the patient. These strategies vary widely depending on the underlying cause and may include medication to alleviate symptoms, specific repositioning maneuvers for BPPV, or vestibular rehabilitation therapy. Vestibular rehabilitation is an exercise-based program designed to reduce vertigo and dizziness, improve gaze stability, and enhance overall balance.