Subjective Visual Vertical (SVV) is a diagnostic test of the inner ear to assess a patient's perception of verticality and detect if there are any signs of an abnormal tilt that may cause dizziness or vertigo. It investigates the function of the utricle, one of two otolith organs located in the vertebrate inner ear, to evaluate the perception of verticality.
As its name suggests, the test is subjective and cannot directly diagnose Acute Vestibular Syndrome (AVS), Ménière's disease, vestibular migraine, vestibular neuritis, or other central nervous system pathologies.[1]