Microincision versus Standard Corneal Incision Phacoemulsification: Visual Outcome.

PURPOSE

To compare the visual outcome of microincision (2.2 mm) with standard (2.75 mm) corneal incision phacoemulsification.

METHODS

In this prospective, randomized comparative study, patients with senile cataract and less than 1 diopter (D) of astigmatism were divided into two groups. Group 1 included patients undergoing phacoemulsification with 2.2 mm clear corneal incision and group 2 included those undergoing phacoemulsification with 2.75 mm incision. The steep axis measured on keratometry was marked preoperatively. Phacoemulsification was performed through clear corneal incision on this steep axis. Assessment of visual acuity (distance and near), keratometry, keratometric cylinder, contrast sensitivity by Functional Acuity Contrast Test, and surgically induced astigmatism (SIA) was performed at 1 day, 1 week, and 1, 3, and 6 months.

RESULTS

Fifty eyes of 50 patients were included in the study (29 were male). There were 25 patients in each group. The mean (±SD) SIA calculated by vector analysis method (Holladay-Cravy-Koch) using keratometry value, at the end of 6 months, was 0.54 (±0.18) D and 0.58 (±0.14) D in groups 1 and 2, respectively (p = 0.27). No significant differences were found in the distance and near uncorrected visual acuity, mean keratometry, keratometric cylinder, contrast sensitivity, and SIA at any follow-up visit between two groups.

CONCLUSIONS

In patients with less than 1 D astigmatism undergoing phacoemulsification, both 2.2-mm and 2.75-mm clear corneal incisions result in similar postoperative visual outcome in terms of SIA, keratometry, and contrast sensitivity.