This is an investigation for detection of peripheral vestibulopathy and early detection of vestibulotoxicity. It assesses the ability of the subject to maintain the image on the fovea, the most sensitive area of the retina, during head movement. This is an important function of the Vestibulo Ocular Reflex (VOR). In normal persons, the image of the moving target is maintained on the fovea by the VOR When the VOR system is impaired, visual acuity degrades substantially during head movement as there is a slip of the image from the fovea causing blurring of vision.
The difference between static and dynamic visual acuity is displayed in graphical form. The test is done with a LOGMAR chart. DVA also helps identify patients likely to benefit from vestibular rehabilitation and is useful in customizing rehabilitation exercises. It is an excellent objective measurement providing a precise indication of patient’s ability to see objects while performing daily activities while on the move.