Vessel-Sparing Rectus Plication Surgery vs Recession/Resection: A Comparative Optical Coherence Tomography Angiography (OCT-A) Analysis of Iris Vessel Density Changes.

OBJECTIVES

To compare the iris vessel density results before and after rectus plication, a vessel-sparing procedure, and resection/recession surgery using a non-invasive method, optical coherence tomography angiography (OCT-A).

METHODS

This single-center, prospective observational study was held in Beyoglu Eye Research and Training Hospital. Ten patients were included in the study after excluding patients with systemic or ocular diseases, nystagmus or fixation loss. The anterior segment module of the OCT-A was utilized, and the eye-tracking feature was disabled to obtain the highest image quality. OCT-A imaging was performed one day before or on the day of the surgery and within three days after surgery.

RESULTS

Ten patients (8 females) were included in the study. Five had esotropia, meanwhile 5 had exotropia. Two patients received muscle plication in one eye, and the other three received one rectus plication and antagonist recession on the same eye. Preoperative and postoperative images were analyzed both qualitatively and quantitatively with device software and ImageJ. The vessel density near the plicated rectus decreased less after surgery. The mean preoperative and postoperative vessel densities were 53.68% and 49.62% in the plication group (p>0.05). However, they were 60.19% preoperatively and 54.26% postoperatively in the resection/recession group (p=0.043).

CONCLUSION

In this study, OCT-A was utilized for the first time to evaluate the qualitative and objective quantitative changes in iris vessel density after rectus plication and recession/resection surgeries. The quantitative comparisons demonstrated that the iris vessel density decreased less after vessel-sparing surgery. Iris OCT-A shows promise for evaluating changes in iris vessel density.