Bioptic Telescopic Spectacles and Driving Rehabilitation for People with Age-Related Macular Degeneration: A Pilot Project

Abstract

Introduction Driving is a multifactorial task of which vision is a component. A person’s ability to meet requirements to gain or maintain a driver’s license may be compromised by visual impairments (VI) caused by ocular diseases such as Age-related Macular Degeneration (AMD). However, vision is only one component of safe driving. Programs aimed at permitting and individually assessing a person’s ability to drive are important for improving the quality of life of Canadians living with VI whose ability to safely drive may be in question. Purpose In Ontario in October 2020, the Highway Traffic Act was amended to allow the use of [bioptic] telescopes to meet provincial visual acuity requirements for Class G licensure for the first time. pending successful completion of an on-road driving assessment while using the telescope (MTO Bioptic Telescope Program). The George & Judy Woo Centre for Sight Enhancement (CSE) in Waterloo, Ontario has formulated a training protocol involving both fitting and training with a bioptic telescope for driving. The aim of this study aim was to determine whether the program sufficiently prepares individuals with AMD to effectively use their bioptic telescope, as determined by success in a simulated in-car evaluation. Methods The study aimed to recruit up to 10 participants with AMD who had lost their driver’s license within the last 5 years, met MTO Bioptic Telescope Program visual requirements and did not suffer from motion sickness or cognitive impairment (by self-report). Visual function and visual perceptual testing as well as bioptic telescope fitting were administered. Participants also proceeded into the CSE training program which included 3-5 training sessions and a counselling session. Participants’ driving skills and use of bioptic telescope(s) were then assessed in a virtual reality SUV driving simulator both with and without the telescope. Results Three participants (mean age of 74 years, male) were enrolled and completed the study. Visual parameters met the eligibility criteria (corrected visual acuity ranged from 0.35logMAR (20/50) to 0.77logMAR (20/126), contrast sensitivity ranged from 1.00-1.45logCS units and visual fields were full peripherally). All three participants had binocular central scotomas identified on Humphrey monocular full field tests and Nidek microperimetry. However, no central scotoma was evident on the Humphrey Estermann binocular field assessment. Each participant was fit with a bioptic telescope (2.2-3x magnification) and completed three training sessions. All participants passed the Scan Course but failed the other visual perceptual tests (Useful Field of View, Trail Making, Motor Free Visual Perceptual Test-4). Participant 3 failed the Montreal Cognitive Assessment for the Blind and Visually Impaired. In the final assessment, Participant 1 successfully completed the driving simulation with and without the telescope with no critical driving errors. Participant 2 passed only with the telescope which was used appropriately to identify traffic and speed signs. Participant 3, despite having the best visual acuity, failed under both conditions with critical errors. Conclusion Although further research is required, several important findings to date have been identified. First, the Esterman binocular visual field test cannot be solely used to determine the full field of those with a potential central deficit. Second, the visual perceptual tests conducted with the cut-offs provided, did not definitively identify those individuals that may not be suitable for driving with bioptics; a functional assessment appears to continue to be the gold standard. Third, full medical evaluation should be conducted prior to the visual function evaluation to help identify those that are not safe driving due to non-visual reasons. Finally, it appears that the CSE Bioptic Fitting and Training Protocol may effectively enable participants to learn to apply the fundamental skills required for using a bioptic telescope in a driving situation.