Abstract
Purpose:
To compare outcomes of toric intraocular lens (TIOL) implantation and monofocal intraocular lens (MIOL) followed by photorefractive keratectomy ( PRK) in cases of pre-existing astigmatism with cataract .
Methods:
60 eyes of 52 patients with age related cataract and regular corneal astigmatism between 1.5 to 3.0D underwent phacoemulsification with TIOL implantation (TIOL group,n=30) or phacoemulsification with MIOL placement followed by PRK 3 months later(MIOL+PRK group,n=30).Parameters analysed were uncorrected best corrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction, contrast sensitivity, glare, aberrations, keratometry and corneal topography.
Results:
Mean UCVA in TIOL group was 0.08 ± 0.09 logMAR and in MIOL+ PRK group was 0.07 ± 0.08 logMAR at 6 months (p=0.6). 53.3% patients in the former and 60% in latter group had UCVA > 20/20. Median BCVA values were comparable among the two groups. Median refractive cylinder values at 1 and 3 months were comparable but at 6 months it was -0.5 in TIOL and 0 in MIOL+PRK group (p= 0.02). Mean refractive cylinder at 6 months was -0.35 ± 0.26 D in TIOL and -0.19 ± 0.23 D in MIOL+PRK group. Mean spherical equivalent at 6 months was -0.12 ± 0.3 D in TIOL and -0.09 ± 0.3 D in MIOL+PRK group. Mean log contrast sensitivity was 1.5 ± 0.05 in TIOL and 1.58 ± 0.061 in MIOL+PRK group (p = 0.5).Mean glare acuity value at 6 months was 0.4 ± 0.1 in TIOL group and 0.7 ± 0.1 in MIOL+PRK group (p = 0.001). Root mean square value (RMS) of total aberrations at 5 mm pupil was 1.0 ± 0.4 microns in the former and 1.2 ± 0.5 microns in the latter (p = 0.04) and RMS at 6 mm pupil was 1.2 microns and 1.82 microns respectively (p = 0.01). Mean toric IOL rotation at 1 month was 1.13 ± 1.9 degrees. Mean SIA was 0.53 ± 0.15 D in TIOL and 0.54 ± 0.11 D in MIOL+PRK group at 1 month (p = 0.8). Power vector analysis showed significant difference in the median JO vector value at 6 months (-0.11 in TIOL and 0 in MIOL+PRK group with p = 0.001). Median J45 vector values were comparable. Mean epithelial healing time was 4.6 ± 0.8 days post PRK. None of the patients developed corneal haze following PRK.
Conclusions:
TIOL implantation is a safer option with superior visual outcomes as compared to MIOL implantation followed by PRK
Keywords: 428 astigmatism •
445 cataract •
567 intraocular lens