Research Article Impact of Carotid Endarterectomy on Choroidal Thickness and Volume in Enhanced Depth Optical Coherence Tomography Imaging El˙ zbieta Krytkowska , 1 Monika Masiuk, 1 Miłosz P. Kawa , 2 Aleksandra Grabowicz, 1 Paweł Rynio, 3 Arkadiusz Kazimierczak, 3 Krzysztof Safranow, 4 Piotr Gutowski, 3 and Anna Machali ´ nska 1 1 First Department of Ophthalmology, Pomeranian Medical University, Szczecin, Poland 2 Department of General Pathology, Pomeranian Medical University, Szczecin, Poland 3 Department of Vascular Surgery and Angiology, Pomeranian Medical University, Szczecin, Poland 4 Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Szczecin, Poland Correspondence should be addressed to Anna Machali´ nska; annam@pum.edu.pl Received 25 September 2019; Accepted 23 January 2020; Published 23 March 2020 Academic Editor: Lawrence S. Morse Copyright © 2020 El˙ zbieta Krytkowska et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Purpose. Carotid endarterectomy (CEA) is considered an effective therapeutic method for improving ocular circulation. e choroid is a predominantly vascular tissue; thus, systemic and local vascular alterations may influence its morphology and function. e aim of the current study was to analyse changes in choroidal thickness and volume in patients with significant internal carotid artery stenosis (ICAS) before and after unilateral CEA. Methods. e 42 eyes of the 21 asymptomatic patients included in the study were divided into two groups: those ipsilateral (EIE) and those contralateral (ECE) to CEA. All participants underwent a complete ophthalmologic examination, including enhanced depth imaging-optical coherence tomography (EDI- OCT). A comparative analysis of subfoveal thickness (CT) and choroidal volume (CV) measured in nine Early Treatment of Diabetic Retinopathy Study (ETDRS) subfields at baseline, on the 2nd day after CEA, and in the 3rd month after CEA was performed. Results.IntheEIEandECEgroups,nosignificantdifferencesineitherCTorCVvaluesbeforeandonthe2nddayafter the CEA were observed. In the EIE group, a significant increase in CT and CV in the 3rd month after CEA compared to baseline was noted in the specific ETDRS region. Changes in CT and CV after surgery were positively correlated with the participants’ physical activity status and diastolic blood pressure and negatively correlated with the participants’ age and smoking status. Additionally, the analysis of changes in CV after CEA showed a positive correlation between the EIE and ECE groups. Conclusions. CT and CV fluctuations in the central and perifoveal areas visualized with EDI-OCT enabled the observation of the processes of tissue adaptation to variable blood flow conditions. 1. Introduction e choroid is one of the most vascularized tissues of the body [1]. Its main function is supplying oxygen and nu- trients to the outer retina, particularly in the foveal avascular zone, where the choroid is the exclusive blood source for the retina [2, 3]. e choroid is considered to have additional functions, such as thermoregulation and secretion of growth factors [1, 2]. Additionally, the choroid plays an important role in the regulation of intraocular pressure (IOP) due to its control of aqueous humour outflow regulation [1]. Localization between the overlying pigmented retinal epithelium (RPE) and the dense, opaque sclera beneath makes the choroid difficult to visualize. Conventional optical coherence tomography (OCT) is affected by the blocking effects of melanin and the scattering properties of the blood Hindawi Journal of Ophthalmology Volume 2020, Article ID 8326207, 11 pages https://doi.org/10.1155/2020/8326207