Title: How to Minimize Corneal Astigmatism during Cataract Surgery

Authors: Dr Silni Chandra, Dr Smitha M.

 DOI:  https://dx.doi.org/10.18535/jmscr/v6i7.19

Abstract

Aims:  To study the corneal astigmatism in manual small incision cataract surgery following temporal incision, superior incision, superotemporal incision and superior incision with infinity suture.

Setting: Government Medical College, Kozhikode; Government Medical College, Palakkad

Design: Retrospective Study

Material and Method: This study included cases of cataract surgery done during 9 months period from January 2016 to September 2016 at Government Medical College Palakkad.  A retrospective Chart review of 199 eyes of 199 patients was done to assess the post operative corneal astigmatism. Visual Acuity & Keratometry was recorded preoperatively and at 2 months post operatively. The results were tabulated into four groups: Superior incision with infinity suture, temporal incision, Superotemporal incision and Superior incision.  Postoperative corneal astigmatism, induced corneal astigmatism and post operative visual acuity were analyzed among the four groups.

Statistics: SPSS analysis, Microsoft Excel

Result: 82 (41.2%) patients had undergone SICS with superior incision, 45 (22.6%) patients had SICS with superior incision with infinity suture, 42(21.1%) patients had undergone SICS with superotemporal  incision and 30 (15%) patients had undergone SICS with temporal incision.

Post operatively the mean corneal astigmatism at two months was significantly higher in the superior with infinity suture group (1.6444 ±0.640) and superior section group (1.548 ± 0.767) and lowest in the temporal (0.4750 ± 0.401) followed by superotemporal section group (1.035 ± 0.656)

The induced corneal astigmatism was lowest in the  in the Temporal section group(-0.158  ±0.3181 followed by 0.2917 ±0.6460 in the superotemporal section group and 0.5722 ±0.6563 in the Superior section with infinity suture group and highest in the superior section group ( 0.7622 ±0.7119). This difference in the four groups is found to be statistically significant (p=0.000).

Conclusion: Temporal incision induces the least corneal astigmatism followed by superotemporal incision. Highest corneal astigmatism is induced by Superior incision. Infinity suture will help in marginally reducing the corneal astigmatism.

Keywords: Cataract, Small Incision, Infinity suture, Superior, Temporal, Superotemporal, Astigmatism.

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Corresponding Author

Dr Silni Chandra