Comment on “The role of specific visual subfields in collisions with oncoming cars during simulated driving in patients with advanced glaucoma”

Kenzo Koike, Glaucoma Fellow, Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX
October 02, 2017

Kenzo J. Koike, MD1; Lauren S. Blieden, MD1,2; Yvonne I. Chu, MD1; Silvia Orengo-Nania, MD1,2; Kristin S. Biggerstaff, MD2; Bac T. Nguyen, MD1; Peter T. Chang, MD1,2; Benjamin J. Frankfort, MD, PhD1

Assessing the visual standards to safely operate a motor vehicle is a challenging topic and discussion that we regularly encounter in our glaucoma population. Multi-centered and population-based studies previously have shown that patients with glaucoma are at particularly increased driving risk, due to their visual deficits.1,2 As such, we greatly appreciate the contributions from Kunimatsu-Sanuki and colleagues, who evaluated patients with advanced glaucoma, and how they performed with a driving simulator. As part of their analysis, the authors focused on specific visual sub-fields, and how those may correlate with the incidence of motor vehicle collisions (MVCs). Their conclusions noted that inferior visual field deficits, age, and visual acuity, were significant factors that contributed to the rate of MVCs. However, we noticed that visual acuity of the better eye (recorded as logMAR) was a significantly higher risk factor (odds ratio of 28.59 and 75.71 for analyses 1 and 2, respectively, as shown in Table 3) for collisions during simulated driving. With such a dramatically higher risk of simulated collision based on visual acuity, it is likely that this parameter alone is the most significant factor to influence the risk of MVCs. As there is some discrepancy in the literature with regard to how visual acuity relates to increased risk of MVC’s in glaucoma patients,3-5 we suggest that these findings be more clearly emphasized. Furthermore, we would appreciate any commentary from the authors regarding visual acuity as a significant risk parameter for MVCs. Specifically, we are interested to know if further analysis of the data would show a particular threshold for visual acuity to incite a significantly higher risk for simulated collision. Given our role to responsibly report the visual capacity of patients to safely operate a motor vehicle, this information may serve useful to further guide visual acuity parameters for motor vehicle licensing.

Author Affiliations:
1. Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX
2. Michael E. Debakey Veterans Affairs Medical Center, Houston, TX

References:
1. Ramulu PY, West SK, Munoz B, Jampel HD, Friedman DS. Driving cessation and driving limitation in glaucoma: the Salisbury Eye Evaluation Project. Ophthalmology. 2009;116(10):1846-1853.
2. Janz NK, Musch DC, Gillespie BW, Wren PA, Niziol LM, Collaborative Initial Glaucoma Treatment Study I. Evaluating clinical change and visual function concerns in drivers and nondrivers with glaucoma. Invest Ophthalmol Vis Sci. 2009;50(4):1718-1725.
3. Yuki K, Awano-Tanabe S, Ono T, et al. Risk Factors for Motor Vehicle Collisions in Patients with Primary Open-Angle Glaucoma: A Multicenter Prospective Cohort Study. PLoS One. 2016;11(11):e0166943.
4. Gracitelli CP, Tatham AJ, Boer ER, et al. Predicting Risk of Motor Vehicle Collisions in Patients with Glaucoma: A Longitudinal Study. PLoS One. 2015;10(10):e0138288.
5. Kwon M, Huisingh C, Rhodes LA, McGwin G, Jr., Wood JM, Owsley C. Association between Glaucoma and At-fault Motor Vehicle Collision Involvement among Older Drivers: A Population-based Study. Ophthalmology. 2016;123(1):109-116.

Conflict of Interest

None declared