Correlation of Straylight and Visual Acuity in Long-Term Follow-up of Manual Descemet Stripping Endothelial Keratoplasty

Purpose: Long-term quality of vision after Descemet stripping endothelial keratoplasty (DSEK) was evaluated and correlated with corneal characteristics and subjective complaints. Methods: Thirty-four eyes were examined; patients had a single visit 6 to 64 months after DSEK for Fuchs dystrophy. Best-corrected distance acuity (BCDA) and straylight were analyzed. To better evaluate long-term postoperative BCDA changes, longitudinal data were used from earlier visits. Corneal thickness was measured with the Visante anterior segment optical coherence tomography. Interface, stromal, and endothelial haze were semiquantitatively graded using the slit lamp. Vision-related quality of life was evaluated with the 39-item National Eye Institute Visual Function Questionnaire and a straylight questionnaire. Correlation analysis comparing corneal characteristics with visual quality was performed. Results: Mean postoperative time was 1027 +/- 453 days. Mean BCDA at this time was 0.33 +/- 0.19 logarithm of the minimal angle of resolution. BCDA remained stable with long-term postoperative follow-up. Straylight averaged 1.47 perpendicular to 0.19, on average 0.12 log units higher than normal for age-related pseudophakic eyes (P <0.001). BCDA correlated with corneal haze (r = 0.50), whereas straylight showed a nonsignificant association (P = 0.12). Neither BCDA nor straylight correlated with corneal thickness. Mean Visual Function Questionnaire 39 score was 77/100, and mean score of the straylight questionnaire was 46/100. Conclusion: Quality of vision after DSEK does not return to normal levels of age-matched pseudophakic eyes, with decreased BCDA and increased straylight. Questionnaire scores indicate mild (Visual Function Questionnaire 39) to moderate (straylight) subjective visual impairment. Corneal thickness and haze do not offer an adequate explanation for the decreased visual quality