Changes in retinal and choroidal thickness after carotid endarterectomy: a systematic review

Carotid endarterectomy is a well-established procedure for enhancing cerebral perfusion in patients with internal carotid artery stenosis. As a multifactorial disease, carotid stenosis can have ocular implications, potentially affecting retinal and choroidal perfusion and contributing to visual dysfunction. This systematic review aims to evaluate changes in choroidal and retinal thickness after unilateral carotid endarterectomy, providing insight into the impact of the procedure on ocular perfusion.

A comprehensive search was performed across PubMed, Scopus, and Web of Science up to July 2024, without restrictions on language or publication date. The inclusion criteria included original studies assessing retinal or choroidal thickness via optical coherence tomography before and after carotid endarterectomy in adults. Additional manual searches of reference lists and citation tracking were employed to ensure completeness. Study quality was appraised via the NHLBI tool for observational studies.

Six prospective observational studies involving 269 patients were included. Findings on choroidal thickness changes after carotid endarterectomy are heterogeneous. While two studies reported significant postoperative Choroidal Thickness increases-one within a week and another at three months-other studies reported no significant changes. One study suggested that higher degrees of carotid stenosis may blunt early Choroidal Thickness response. Retinal measurements were less consistently assessed; among the three studies that evaluated retinal nerve fibre layer and ganglion cell complex thickness, no consistent postoperative changes were observed. Overall, variability in study designs, Optical Coherence Tomography protocols, and follow-up durations limits comparability, precluding meta-analysis.

This review highlights a potential association between carotid endarterectomy and improved ocular perfusion, as reflected by changes in choroidal thickness. However, inconsistencies across studies and limited data on retinal structural outcomes underscore the complexity of this relationship. These findings emphasize the need for larger, standardized studies to clarify the impact of carotid revascularization on the ocular microvasculature and guide future clinical practice.