Purpose:
In approximately 40 US states, drivers who cannot meet vision standards with conventional optical correction are permitted to use bioptic telescopic spectacles (BTS) to obtain licensure. The presence of nystagmus could cause difficulty with use of BTS. The impact of documented nystagmus on hours of driver training and obtaining licensure was examined in a cohort of Ohio bioptic drivers.
Methods:
We performed a retrospective review of records of patients who completed an initial bioptic examination at the College of Optometry at the Ohio State University. Patients were identified by CPT code in the College’s patient record system. Data were collected on vision, including visual acuity (logMAR charts) and visual field (arc or Goldmann perimeter). Demographics, ocular diagnosis, licensure history, and documented hours of driver training were also recorded. Relationships among nystagmus, hours of training before the driving instructor judged the patient ready for a road test, vision data, eventual licensure, and driving experience were investigated using multiple regression models.
Results:
80 patients were identified as having completed an initial vision examination, and presence or absence of nystagmus was documented for 75 of those patients (26 with documented nystagmus). Age at initial exam ranged from 17 to 79 years (mean±SD = 39±15 years). Patients with nystagmus were younger (31±12 vs. 43±15 years) than those without nystagmus (p < 0.001). LogMAR visual acuity was 0.71±0.15 for patients with nystagmus and 0.67±0.21 for those without (p=0.40). Patients with nystagmus had 23±20 documented hours of training, compared with 11±9 for patients without. 12% of patients with nystagmus reported prior (non-bioptic) driving licensure at the initial exam, compared with 88% of drivers without nystagmus. When previous driving licensure was controlled for, nystagmus was not a significant predictor of hours of training received (p=0.85) or eventual licensure (p=0.80).
Conclusions:
Patients with nystagmus reporting for a bioptic vision exam were younger and less likely to have previous driving experience. When controlling for driving experience, nystagmus was not a significant predictor of hours of training received or eventual licensure.
Keywords: low vision • nystagmus