Effects of Dilation on Electronic-ETDRS Visual Acuity in Diabetic Patients

• Published in: Investigative ophthalmology & visual science 2009-04, Vol.50 (4), p.1580-1584
• Main Authors: Sun, Jennifer K, Aiello, Lloyd Paul, Stockman, Margaret, Cavallerano, Jerry D, Kopple, Ann, Eagan, Sharon, Qin, Haijing, Kollman, Craig, Beck, Roy W, Glassman, Adam R, Diabetic Retinopathy Clinical Research Network
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Diabetes Mellitus - physiopathology; Diabetes. Impaired glucose tolerance; Diagnosis, Computer-Assisted; Drug Combinations; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Eye and associated structures. Visual pathways and centers. Vision; Female; Fundamental and applied biological sciences. Psychology; Humans; Male; Medical sciences; Middle Aged; Mydriatics - administration & dosage; Ophthalmology; Phenylephrine - administration & dosage; Pupil - drug effects; Pupil - physiology; Reproducibility of Results; Tropicamide - administration & dosage; Vertebrates: nervous system and sense organs; Vision Tests - instrumentation; Vision Tests - standards; Visual Acuity - physiology
• ISSN: 0146-0404; 1552-5783; 1552-5783
• DOI: 10.1167/iovs.08-2426

To evaluate the effect of pupillary dilation on electronic-ETDRS visual acuity (EVA) in diabetic subjects and to assess postdilation EVA as a surrogate for predilation VA. DRCR.net-protocol refraction and EVA were measured before and after dilation in diabetic subjects by independent, masked examiners. In 129 eyes of 66 subjects, the median (25th, 75th percentiles) predilation EVA score was 69 (54, 86) (Snellen-equivalent 20/40(-1) [20/80(-1), 20/20(+1)]). Predilation VA was >or=20/20, or=10 letters (>or=2 ETDRS lines) in 19% of eyes. Extent of change (range +12 to -25 letters) was associated with baseline VA. No relationship was identified between EVA change and gender, race, lens status, refractive error, DR severity, or primary cause of vision loss. In an optimized clinical trial setting, there is a decline in best corrected EVA after dilation in diabetic subjects. The large range and magnitude of VA change preclude using postdilation EVA as a surrogate for undilated VA.