Redistribution of strain and curvature in the porcine anterior lens capsule following a continuous circular capsulorhexis.

Cataract surgery is the most commonly performed surgical procedure in the US, it consists of three steps: introduction of a hole into the lens capsule, removal of the clouded lens through this access hole, and insertion of an artificial lens. We hypothesize that errant behavior by the residual epithelial cells of the lens capsule following surgery are due, in part, to surgically-induced changes of the native stress and strain fields in the lens capsule. Because the capsular bag can be regarded mechanically as a membrane, here we study changes in curvature and strains due to the most common means of introducing the initial access hole: a continuous circular capsulorhexis (CCC). We show that a modest sized CCC increases circumferential strains and decreases meridional strains by up to approximately 20% and that curvatures change by up to approximately 13%, particularly near the edge of the CCC. We submit that such changes can induce mechanobiological responses that are responsible, in part, for some of the long-term complications following cataract surgery.

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