The Medical Physics & Bioengineering department was approached by Leeanne Yeoman at the Brain Injury Rehabilitation Service (BIRS) at Burwood Hospital, regarding the design of a low-cost video Frenzel system for diagnosing vestibular dysfunction in their patients.
The basic design of a Frenzel Video system consists of a pair of goggles blacked out to create complete darkness, thereby eliminating visual fixation. A video camera attached to one of the lenses and is illuminated by an infrared light source to enable an image to be displayed and recorded on a computer.
Our goggles are specially modified to block out all natural light which is not as easy as it sounds! The camera and infrared light source are magnetically attached and so can be easily moved between left and right eyes.
A second camera in the clinic simultaneously captures the movement of the patient and conversation between the patient and clinician. Both of these videos are recorded together as picture-in-picture so the movement of the eye and movement of the patient are always synchronised. The videos and audio are automatically captured and compressed using open-source software.
This device has been successfully trailed at Burwood Hospital and devices are now being used by BIRS and also by Balance Works Physiotherapy.