BACKGROUND: Cataract surgery has been shown to induce choroidal remodeling, but the underlying mechanisms remain poorly understood. This study investigates the relationship between preoperative lens opacity and postoperative changes in choroidal vascularity following phacoemulsification.

METHODS: This prospective study included 46 eyes from 46 patients undergoing routine cataract surgery. Choroidal vascularity was assessed using optical coherence tomography angiography (OCTA) before surgery and at 1, 4, and 12 weeks postoperatively. The choroidal vascularity index (CVI) was calculated using a custom computer script. Preoperative lens opacity was quantified using anterior segment optical coherence tomography (AS-OCT). Correlations between CVI changes and various surgical and anatomical parameters were analyzed.

RESULTS: The CVI decreased significantly, from 0.584 ± 0.036 preoperatively to 0.569 ± 0.037 at 12 weeks postoperatively (p = 0.003). There was a significant negative correlation between the change in CVI and preoperative lens density (r = - 0.333, p = 0.036), as well as nuclear density (r = - 0.328, p = 0.039). No significant correlations were found between CVI change and cumulative dissipated energy, phacoemulsification time, fluid usage, or intraocular pressure change.

CONCLUSION: Cataract surgery induces a significant decrease in choroidal vascularity that persists for at least three months postoperatively. This decrease correlates with preoperative cataract density, suggesting that increased light transmission following lens replacement may lead to choroidal remodeling. Consequently, objective measurement of lens opacity may contribute to the decision-making process for timing cataract surgery; however, further studies are needed to evaluate its potential role in minimising short- and long-term complications, such as macular oedema or age-related macular degeneration.