This study in the April issue of the Journal of Cataract & Refractive Surgery evaluated the long-term wound-healing changes in clear corneal cataract incisions (CCIs) using Fourier-domain optical coherence tomography (OCT). The authors found that Descemet membrane detachment and posterior wound gape appeared in the early postoperative period and persisted for up to three months. In contrast, posterior wound retraction emerged two to three weeks postoperatively and was present in 90 percent of eyes after three years.
Previous studies have evaluated short-term architectural changes in CCIs up to one month after cataract surgery using anterior-segment OCT, but the authors are unaware of any other long-term studies.
They reviewed 84 consecutive cases (127 eyes) seen at one medical institute between one day and 15 years after cataract surgery and IOL implantation performed by one of two surgeons.
The results indicate that Descemet membrane detachment was present in 37.1 percent of eyes one day postoperatively but only 4.5 percent at one to three months (P = 0.005) and completely absent after three months. Posterior wound gape decreased from 85.7 percent of eyes at one day to 31.8 percent at one to three months (P < 0.001) and none after three months.
Posterior wound retraction was observed in no eyes before two weeks after surgery but 33.3 percent of eyes at two to three weeks, 75 percent at one to three years and 90.5 percent after three years (P < 0.001), indicating long-term remodeling of the incision. Mean wound retraction was 120 mm, which was 7.5 percent of the radial incision length. The authors say that posterior wound retraction may induce changes in anterior and posterior corneal curvatures and thereby alter corneal power, astigmatism or both.
In cases in which posterior wound retraction was observed, the cornea peripheral to the incision appeared thinner than the cornea that was more central. This could be due to contraction of the limbal aspect of the wound, thickening of the tissue central to the corneal wound and wound-healing processes in the cornea, including wound slippage, myofibroblast contracture within the stroma, and localized endothelial hypertrophy and Descemet membrane deposition.
The authors say that wound healing and retraction may be directly related to the geometry of the incision, with other factors possibly playing a role, including patient age, corneal thickness and early postoperative wound features, such as misalignment and magnitude of edema.