Prospective Evaluation of Mesopic Night Vision and Night Vision Goggle Visual Acuity After Photorefractive Keratectomy (PRK)

摘要

The US Air Force PRK Study involved 98 non-flying, active duty volunteer personnel. All study subjects underwent a comprehensive array of vision tests. Baseline and post-operative data were collected at the Ophthalmology Branch of the Clinical Sciences Division of the USAF School of Aerospace Medicine, in partnership with the Air Force Research Laboratory and Wilford Hall Medical Center. This report covers results from pre- and post- operative night vision goggle (NVG) visual acuity testing. 65 treated subjects and 15 untreated controls completed all post-op visits through 12 months, and 52 treated subjects and 14 untreated controls through 24 months. NVG acuities were collected on a high contrast letter chart (Bailey-Lovie), and custom made grating charts. There was a statistically significant loss of letter acuity at the 4- and 6-month post-op visits for treated subjects but not controls. Acuity returned to baseline levels by 12 months. Mean loss of acuity for groups was typically only a few letters; however, treated subjects were more likely to lose than gain acuity beyond that predicted from repeatability studies with controls.