Effect of biaxial versus coaxial microincision cataract surgery on optical quality of the cornea.

Context: Visual function is determined by a combination of the cornea, which has a larger effect and internal aberrations generated by the intraocular lens and those induced by the surgery. These corneal refractive changes are related to the location and size of the corneal incision. The smaller the incision, the lower the aberrations and the better the optical quality. Aims: To compare the effect of uneventful coaxial versus biaxial microincision cataract surgery (MICS) on the corneal aberrations. Settings and Design: Retrospective interventional nonrandomized comparative case study comprised 40 eyes of 36 patients with primary senile cataract. Subjects and Methods: They were divided into two groups: Group I (20 eyes) had operated by biaxial MICS and Group II (20 eyes) had operated by coaxial MICS. Each group were assessed by corneal topography and wavefront analysis over 6 mm pupil size preoperatively and 1‑month postoperatively. Statistical Analysis Used: Statistical analysis was performed using SPSS for Windows (version 17.0.1, SPSS, Inc.). The paired t‑test was used to compare the mean values of corneal aberrations preoperatively and 1‑month postoperatively in each group. Results: There was a significant increase in trefoil and quatrefoil in biaxial MICS (P = 0.063, 0.032 respectively) while other aberrations insignificantly changed. The coaxial MICS showed a significant increase in root mean square (RMS) of total high order aberrations (HOAs) (P = 0.02) and coma (0.028), but not the others. In comparison to each other, there was the insignificant difference as regards astigmatism, RMS of individual and total HOAs. Conclusions: Coaxial and biaxial MICS are neutral on corneal astigmatism and aberrations.

Comparison of Clinical Outcomes between Different IOL Sizes after Microincisional Cataract Surgery

PURPOSE: To compare clinical outcomes between different IOL sizes after microincisional cataract surgery. METHODS: Retrospective chart review was done in 68 eyes of 68 patients who underwent phacoemulsification and implantation with two different-sized aspheric IOLs (AKREOS MI60 Bausch & Lomb, Inc., Rochester, NY). The patients were divided into 2 groups: group I consisted of 38 eyes between 15.5-22.0 diopter (D) (optic size 6.0 mm, overall size 10.7 mm), and group II consisted of 30 eyes between 22.5-30.0 D (optic size 5.6 mm, overall size 10.5 mm). The best corrected visual acuity (BCVA), refractive error, and anterior chamber depth (ACD) were measured preoperatively and postoperatively and were compared between groups. RESULTS: Postoperative 6 month BCVA was 0.08 +/- 0.10 D in group I and 0.07 +/- 0.11 D in group II. During the same period, the spherical equivalent was -0.32 +/- 0.65 D in group I and -0.16 +/- 0.59 D in group II (p > 0.05). There were no significant differences in ACD or refractive error during the postoperative period (p > 0.05). CONCLUSIONS: Comparison of postoperative visual acuity and spherical equivalent between different sizes of Akreos MI-60(TM) IOLs showed no differences.

Clinical Outcomes After Microincision Cataract Surgery and In-the-bag Implantation of a New Intraocular Lens

PURPOSE: To compare visual performance after microincision cataract surgery (MICS) with the implantation of the Akreos MI-60 (MI-60) intraocular lens (IOL) through a 1.8-mm microincision with that after conventional cataract surgery with implantation of the Akreos Adapt-AO IOL (Adapt-AO). METHODS: All MICS procedures were performed by the same surgeon. The MI-60 was implanted into 25 eyes, and the Adapt-AO was place in 28 eyes. Best corrected visual acuity (BCVA), total high-order-aberration (HOA), contrast sensitivity, and surgically- induced astigmatism (SIA) were recorded one-week, one-month, and four-months postoperatively. RESULTS: There were no statistically significant differences in BCVA between eyes implanted with the MI-60 or those with the Adapt-AO (MI-60 vs. Adapt-AO, 0.09+/-0.11 at baseline (logMAR), 0.11+/-0.08 at one-week, 0.06+/-0.07, 0.06+/-0.06 at one-month, 0.05+/-0.06, 0.06+/-0.05 at four-months according to the Mann-Whitney U test, p>0.05). Refractive errors were significantly less with the Adapt-AO than with the MI-60 (MI-60 vs. Adapt-AO, -0.50+/-0.43 at baseline (diopter), -0.06+/-0.39 at one-week, -0.50+/-0.41, 0.01+/-0.57 at one-month, -0.46+/-0.36, 0.08+/-0.58 at four-months according to the Mann-Whitney U test, p<0.05). There were no statistically significant differences in total HOA or contrast sensitivity between eyes implanted with the MI-60 and those implanted with the Adapt-AO. SIAs were significantly reduced in eyes implanted with the MI-60 than in those with the Adapt-AO at one-month and four-months postoperatively (Mann-Whitney U test, p<0.05). CONCLUSIONS: Implantation with either the MI-60 or the Adapt-AO produced clinically acceptable outcomes, including good spherical aberration and contrast sensitivity. Furthermore, implantation with the MI-60 caused less SIA at one- and four-months postoperation, as compared to that with the Adapt-AO.

Endothelial Cell Damage in Microincison Cataract Surgery and Coaxial Phacoemulsification

PURPOSE: To evaluate the damage to corneal endothelial cells following coaxial phacoemulsification and bimanual microincision cataract surgery (MICS). METHODS: We measured and compared the changes in the corneal endothelial mean cell density, cell size variation coefficient, hexagonality, and central corneal thickness in senile cataract patients who had received either coaxial phacoemulsification (Group 1, n=20), MICS using ultrasound (Group 2, n=20), and MICS using laser (Group 3, n=20). The endothelial cell parameters and corneal thickness were evaluated preoperatively and at 1 week, 1 month, and 2 months postoperatively. RESULTS: There was no significant difference among the three groups in terms of the endothelial cell parameters and corneal thickness during two months (p>0.05). CONCLUSIONS: MICS is a safe technique that does not appear to be associated with more damage to the corneal endothelium than coaxial phacoemulsification. A longer follow-up study is necessary to investigate its potential benefits for replacing conventional surgery.