Long-term impact of carotid endarterectomy on choroidal and choriocapillaris perfusion

Abstract

Purpose : The long-term impact of carotid endarterectomy (CEA) on choroidal and choriocapillaris (CC) perfusion was investigated using swept-source optical coherence tomography angiography (SS-OCTA) imaging before and after surgery in patients with clinically significant carotid artery stenoses (CAS).

Methods : In this prospective observational study, patients with clinically significant CAS undergoing unilateral CEA had SS-OCTA imaging performed in both eyes prior to surgery (baseline), within one week (short-term follow-up, STFU) and 1-6 months (long-term follow-up, LTFU) after the surgery. The mean choroidal thickness (MCT), choroidal vascular index (CVI), choroidal volume (CV), percentage of choriocapillaris deficits (CC FD%) and choriocapillaris thickness (CCT) measurements within 2.5mm foveal-centered circles were assessed using previously validated semi-automated algorithms. Covariance pattern models with a compound symmetry correlation structure between fellow eyes and an unstructured correlation matrix for longitudinal correlation of visits were used to analyze the data.

Results : A total of 58 eyes from 29 patients, with an average age of 72.6±7.7 years were enrolled. The mean degree of stenosis was 86.4%±9.1% on the surgical side and 40.0%±25.5% on the nonsurgical side. On the surgical side post CEA, there was a significant increase in MCT and CVV at STFU as compared with baseline (p<0.001 for both). Additionally, MCT at LTFU remained significantly increased compared with baseline (p<0.001). Moreover, there were no statistically significant differences in CVI, CC FD% and CCT at both STFU (surgical: p=0.08, 0.66 and 0.03) and LTFU (surgical: p=0.35, 0.96 and 0.08) as compared with baseline. On the nonsurgical side, no significant changes were seen in all choroidal and CC parameters at either STFU or LTFU.

Conclusions : CEA led to an immediate reperfusion of the choroid as evidenced by rapid increases in choroidal volumetric measurements (MCT and CVV) at acute postoperative period . This positive effect persisted at long-term only for MCT. The mechanism behind why the benefits were not maintained over time for other choroidal parameters (CVV o CVI) remains a question and awaits further exploration. To comprehensively evaluate the efficacy of CEA in enhancing ocular perfusion, additional information such as flow velocity should offer valuable insights.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.