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Review
. 2022 Nov;70(11):3779-3784.
doi: 10.4103/ijo.IJO_1034_22.

Factors affecting surgically induced astigmatism in manual small-incision cataract surgery

Smriti Nagpal Gupta  1 , Ruchi Goel  2 , Sushil Kumar  2
Affiliations
Review

Factors affecting surgically induced astigmatism in manual small-incision cataract surgery

Smriti Nagpal Gupta et al. Indian J Ophthalmol. 2022 Nov.

Abstract

Cataract is the most common cause of avoidable blindness in the world. While cataract surgery is continually evolving, manual small-incision cataract surgery (MSICS) still remains highly relevant, especially with the threat of the coronavirus disease 2019 (COVID-19) still looming large over the world. MSICS today has a renewed significance, since it does not involve the use of any advanced machinery and relies mainly on easily sterilizable instruments, thereby making it a safe and inexpensive option. A self-sealing valvular tunnel entry forms the basis of MSICS, and proper positioning and construction of the tunnel is imperative to the success of the surgery. With more and more people demanding spectacle independence after surgery, it becomes important to have a thorough understanding of the factors that may influence surgically induced astigmatism in MSICS. These include the incision location, size and shape, configuration of the sclero-corneal tunnel, pre-existing ocular pathology, role of sutures, amongst others. With proper knowledge, many of these factors can be modulated to achieve best results.

Keywords: Astigmatism; MSICS; cataract surgery; incision construction; surgically induced astigmatism.

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Conflict of interest statement

None

Figures

Figure 1
Figure 1
Square incisional geometry, where wound length (C to D) equals wound width (A to C). C: Corneal part of tunnel. L: Limbal part of tunnel. S: Scleral part of tunnel
Figure 2
Figure 2
Adequate scleral cautery
Figure 3
Figure 3
Koch’s incisional funnel. A: Smile incision. B: Straight incision. C: Frown incision. D: Chevron incision
Figure 4
Figure 4
Appropriate depth of tunnel based on partial visualization of crescent knife
See this image and copyright information in PMC

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