Effect of central hole location in phakic intraocular lenses on visual function under progressive headlight glare sources

Abstract

Purpose: To analyze the effect of the central hole location in the V4c implantable collamer lens (ICL) on the quality of vision, including progressive headlight glare simulation and quality of life. Setting: IOBA-Eye Institute, Valladolid, Spain. Design: Case series. Methods: The central hole location was determined by slitlamp and dual Scheimpflug imaging for 6 months or more postoperatively. The visual acuity, mesopic contrast sensitivity, halogen glare contrast sensitivity, xenon glare contrast sensitivity, photostress recovery time after glare, de Boer scale, and Quality of Life Impact of Refractive Correction (QIRC) questionnaire results were evaluated. Multiple regression models were used to analyze the effect of the central hole location on parameters using the pupil center and visual axis as references based on Cartesian and polar coordinates. Results: The safety index was 1.13 and the efficacy index, 1.12. Under all testing circumstances, central hole decentration did not affect the visual acuity or contrast sensitivity. With the visual axis as a reference, worse QIRC values were associated with greater upward central hole displacement (P = .03) and a lower polar angle value (P = .008); also, halogen glare discomfort was greater with a higher radius (P = .04). Using the pupil center as a reference, greater nasal central hole decentration was associated with longer xenon glare photostress recovery time (P = .002). Conclusions: Implantation of the ICL with a central hole yielded excellent visual outcomes, even under increasing glare sources, regardless of the hole's location. However, hole decentration might affect patient-perceived quality of life, bothersome halogen glare, and longer xenon glare photostress recovery time. Such complaints after the early postoperative period might be managed with discrete ICL centration if the central hole is decentered upward or nasally.