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AIM: To evaluate the effect of symmetrical arc incision correcting corneal astigmatism in femtosecond laser-assisted phacoemulsification (FLACS). METHODS: This study enrolled patients with cataract combined with regular corneal astigmatism of >0.75 D, who underwent FLACS. Symmetrical arc incision was set at 8 mm diameter and 85% depth. The follow-up time was 3-24mo (4.92±3.49mo). Pentacam recorded the corneal astigmatism and higher-order aberration at pre-operation and post-operation. The changes in corneal astigmatism were analyzed by Alpins method. The correlation of astigmatism type, age, corneal horizontal diameter, corneal thickness, arc incision length, and correction index (CI) was analyzed, and the residual corneal astigmatism was compared with the residual whole eye astigmatism. RESULTS: Totally 79 patients (102 eyes) were enrolled, 10 patients had corneal epithelial injury, 1 patient occurred corneal epithelial hyperplasia. The corneal astigmatism was 1.23±0.38 D pre-operation, and decreased to 0.76±0.39 D post-operation (t=10.146, P=0.000). Corneal high-order aberration was 0.17±0.08 µm pre-operation and 0.24±0.11 µm post-operation (t=-5.186, P=0.000). The residual corneal astigmatism and residual whole eye astigmatism were no significant difference (t=-0.347, P=0.729). Using Alpin's method, the following were determined: target-induced astigmatism (TIA) =1.23±0.38 D, surgery-induced astigmatism (SIA) =0.77±0.45 D, difference vector (DV)=0.77±0.39 D, and CI=0.54±0.28. Age, astigmatism size, corneal horizontal diameter, corneal thickness, and arc incision length were not correlated with CI. The CI for against the rule astigmatism (ATR) was better than that for with the rule astigmatism (WTR; P=0.001). CONCLUSION: Femtosecond laser-assisted astigmatic keratotomy has better CI of ATR, but increase higher-order corneal aberration. CI is not ideal, it's not a perfect choice if we pursue ideal correction effect.
RESUMEN
OBJECTIVE: To evaluate the visual outcome of +3.00 D aspheric intraocular lens (IOL) implantation and compare it with the previous +4.00 D aspheric AcrySof ReSTOR multifocal IOL. METHOD: It was a case-control study. Sixty patients (120 eyes) from the Tianjin Medical University Eye Center between Jan. 2009 and Dec. 2010 were enrolled into two groups. Twenty patients were assigned to each group respectively. Parameters analyzed included contrast sensitivity, distance uncorrected and best-corrected visual acuity, distance corrected near visual acuity, intermediate visual acuity (60 cm) under bright light condition (100 cd/m(2)) and dim light condition (6 cd/m(2)), through-focus measurement, spectacle independence survey 6 months after second-eye surgery. Independent-samples t tests were used to statistically analyze. RESULTS: In the +3.00D ReSTOR group, LogMAR visual acuity in bright (dim) light was 0.10 (0.24), 0.24 (0.41), 0.14 (0.41) at distant, intermediate and near distance, respectively. While in the +4.00 D ReSTOR group, it was 0.09 (0.23), 0.42 (0.48), 0.15 (0.36), respectively. There was significant difference at intermediate vision between these two groups (P = 0.001). The best near distance was approximately 7 cm out in the +3.00 D IOL group. The percentages of patients not wore glasses for daily activities in +3.00 D and +4.00 D ReSTOR groups were 76% (23/30) and 73% (22/30), respectively. No significant visual interference problems were noted in both groups. CONCLUSION: The +3.00 D aspheric AcrySof ReSTOR IOL achieves a more satisfactory intermediate distance vision when compared with the +4.00 D aspheric IOL.
