Evaluation of Straylight and Contrast Sensitivity After Implantation of Toric Aspheric IOL
Purpose
The purpose of this study was to evaluate the functional results and quality of vision after implantation of an aspheric, aberration-neutral, monofocal toric intraocular lens (IOL).
Methods
18 eyes of 13 patients (median age: 56 years) have so far been enrolled in this ongoing prospective clinical study. The T-flex aspheric, aberration-free toric IOL (Rayner Intraocular Lenses Limited, UK) was implanted after femtosecond or standard phacoemulsification. Follow-up examinations were performed two to four months after surgery; these included subjective refraction, ETDRS uncorrected (UDVA) and corrected distance visual acuity (CDVA), wavefront analysis, measurements of stray light (C-Quant), assessment of contrast sensitivity (Functional Vision Analyzer) and a questionnaire.
Results
Median UDVA was 0.06 logMAR (range: 0.30 to -0.18 logMAR) postoperatively. Median CDVA increased from 0.20 logMAR (range: 0.64 to 0.00 logMAR) preoperatively to -0.07 logMAR (range: 0.16 to -0.26 logMAR) postoperatively. The median difference between achieved versus intended spherical equivalent was -0.08 D (range: -1.25 to +0.65 D). Median subjective cylinder improved from -2.00 D (range: -6.50 to -0.25 D) preoperatively to -0.50 D (range: -1.25 to 0.00 D) postoperatively. The median spherical aberrations (6 mm pupil size) were -0.38 µm (range: -0.69 to -0.10 µm) postoperatively. Measurements of stray light (C-Quant) revealed a median value of 1.28 log(s) (range: 0.92 to 1.61 log(s)).
Conclusion
The T-flex aspheric toric IOL provided beneficial and predictable functional results after surgery. The implantation of the T-flex is an effective method to correct a large range of corneal astigmatism.