Related Experiment Videos
Evaluation of visual function following neodymium:YAG laser posterior capsulotomy
B V Magno1, M B Datiles, M S Lasa
1Ophthalmic Genetics and Clinical Services Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA.
Purpose:
Improvement in visual acuity is the primary endpoint for successful neodymium:YAG (Nd:YAG) laser posterior capsulotomy for posterior capsule opacification. There is limited information on related parameters of visual function that may also improve after laser treatment. The authors evaluate changes in contrast sensitivity and glare disability, aside from visual acuity, following Nd:YAG laser posterior capsulotomy.
Methods:
Measurements of visual acuity, contrast sensitivity (using the Pelli-Robson chart), and glare disability (using the Brightness Acuity Tester [Mentor O & O, Inc., Norwell, MA]) were obtained from 24 consecutive patients before and after Nd:YAG laser posterior capsulotomy. Glare testing was done with both the Pelli-Robson and Early Treatment Diabetic Retinopathy Study (ETDRS) charts. The degree of glare disability was indicated by the difference between visual function with glare (at medium and high settings) and without glare. Prelaser measurements were taken within 2 weeks prior to treatment, and postlaser measurements were obtained within 3 months after treatment. Only one eye per patient was evaluated.
Results:
Mean differences between prelaser and postlaser measurements were significantly different from zero: (1) Contrast sensitivity, mean difference = 0.24 log units (P < 0.0001); (2) High glare disability using Pelli-Robson chart, mean difference = 0.15 log units (P = 0.004); (3) Visual acuity using ETDRS chart, mean difference = 11 letters (P < 0.0001); 4) High glare disability using ETDRS chart, mean difference = 7 letters (P = 0.005).
Conclusions:
Using the above methods for visual function testing, Nd:YAG laser capsulotomy is shown to significantly improve visual acuity, contrast sensitivity, and glare disability measurements as compared with prelaser values. The ophthalmologist may find it helpful to document the last two measurements prior to Nd:YAG laser capsulotomy, especially in patients who have good visual acuity but complain of glare sensitivity.