Purpose:
Patients have come to expect refractive perfection after cataract surgery. 15-20% of cataract patients have 1.0-3.0 D of preexisting astigmatism. LRIs and toric IOLs are both frequently used to correct astigmatism, but a randomized comparative prospective study is lacking in the literature. This study aims to determine which method for astigmatism correction at the time of cataract surgery is more effective: toric IOLs or LRIs.
Methods:
Six patients who had been scheduled for cataract surgery and were found to have 1.5-3.0 D of astigmatism were randomized to two patient groups. One group underwent standard cataract surgery combined with LRIs, while toric IOLs were used to correct astigmatism in the second group. Preoperative and postoperative studies were performed to include visual acuity, manifest refraction, manual keratometry, wavefront analysis, pentacam zernike analyis, and pentacam Q-value analysis. Results were compared between the two groups.
Results:
Wavefront root mean square analysis of each group demonstrated a greater reduction of total aberrations in the toric group. There was also a statistically significant greater decrease in wavefront root mean square coma in the toric group in comparison to the LRI group (p=0.009). Finally, there was a statistically significant greater reduction in astigmatism by manifest refraction in the toric group in comparison to the LRI group (See image, p=0.03).
Conclusions:
Statistical analysis demonstrated significantly better reduction of astigmatism as measured by manifest refraction with toric IOLs, as well as greater reduction in higher order aberrations as determined by wavefront analysis. LRIs did not perform better than toric IOLs by any of the measured criteria. Therefore, we conclude that toric IOLs offer a more effective means for correcting astigmatism at the time of cataract surgery.
Keywords: cataract • astigmatism • intraocular lens