Visual Vertical vs SVV

Visual Vertical makes high-grade subjective visual vertical (SVV) testing accessible to every practitioner — no expensive equipment required. SVV testing is a sensitive, validated measure for brainstem lesions and otolithic dysfunction, widely used in neurology and vestibular rehabilitation. Until now, accurate testing required bulky, costly apparatus. Visual Vertical changes that: all you need is your iPhone, a bucket, and a small piece of Blu Tack. How it works Mount your iPhone inside the bottom of a bucket using Blu Tack. The patient holds the bucket to their face and adjusts a line on screen until it appears vertical to them. The app records the deviation and calculates your result — accurate readings in minutes, at a fraction of the traditional cost. What you can measure - Left eye, right eye, or both eyes open - Single readings or full sequences across all conditions - One or three readings per condition, with automatic averaging Clean, minimal results screens make it easy to record and communicate findings.

Subjective Visual Vertical (SVV) is a test that measures the difference between a person’s perceived vertical and the true vertical. It evaluates gravity perception mediated by the otolith organs, vestibular nerve, and central vestibular pathways, and helps detect asymmetry of vestibular function. Using an audio/video remote control or a variety of game controllers, including those for Nintendo Switch, PlayStation, and Xbox, the user adjusts a displayed line until it is perceived as perfectly vertical. After repeating this procedure 10 times, the application calculates the mean deviation from the true vertical and the standard deviation.