drehtest

A drehtest is a type of diagnostic test used primarily in the field of audiology to assess vestibular function, specifically the rotational response of the semicircular canals. This test involves the patient being seated in a specialized chair that can be rotated horizontally at controlled speeds. Sensors, often videonystagmography (VNG) equipment or infrared cameras, are used to track eye movements (nystagmus) that occur as a reflex response to the rotation. The brainstem uses information from the vestibular system, particularly the horizontal semicircular canals, to stabilize gaze during head movements. When the head rotates, fluid within the canals moves, stimulating hair cells that send signals to the brain. The eyes then move in the opposite direction of the head to maintain a stable visual field. Abnormalities in the pattern, velocity, or latency of the nystagmus during a drehtest can indicate a vestibular deficit. This can help differentiate between peripheral vestibular disorders (affecting the inner ear) and central vestibular disorders (affecting the brainstem or cerebellum). The test is typically performed by an audiologist or a vestibular specialist and involves various rotational speeds and directions to comprehensively evaluate the vestibular system's response.