Regional Differences of Choroidal Structure Determined by Wide-Field Optical Coherence Tomography

Abstract

Citation: Kakiuchi N, Terasaki H, Sonoda S, et al. Regional differences of choroidal structure determined by wide-field optical coherence tomography. Invest Ophthalmol Vis Sci. 2019;60:2614-2622. https://doi.org/ 10.1167 PURPOSE. To compare the submacular to the perimacular choroidal structure in images obtained by wide-field optical coherence tomography (OCT).METHODS. Thirty eyes of 30 healthy volunteers (15 men) were studied. Twelve wide-field radial circumferential scans were recorded with enhanced depth imaging OCT from the macular and perimacular zones. The sizes of the luminal and stromal areas of the choroid were determined. The two zones were subdivided into the superior, inferior, nasal, and temporal sectors. The total choroidal area, the luminal and stromal areas, and the luminal ratio of each sector were compared. RESULTS.All of the choroidal structural parameters analyzed in the present study were largest in the superior sector followed by the temporal, inferior, and nasal sectors. The coefficients of variation were larger in the perimacular zone than in the macular zone: The luminal ratio in the macular zone varied by 1.2%, and that in perimacular zone varied by 4.2%.CONCLUSIONS. The variations in the ratios of the luminal areas of the choroid in the wide-field OCT images are slight in the macular zone but considerable in the perimacular zone.

Impact of Carotid Endarterectomy on Choroidal Thickness and Volume in Enhanced Depth Optical Coherence Tomography Imaging

“…Kakiuchi et al indicated that there was a smaller luminal area within the inferior perimacular region compared to the superior area in a healthy population. is is probably due to the influence of gravity on the direction of flow, which may lead to an increase in intravascular pressure within the choroid located in the superior parts [36]. Additionally, the final stage of disc cup closing is located within the lower segments, which is also a common location of a choroidal coloboma, which may indicate a weaker vascularization of this choroidal region [36,37].…”

“…is is probably due to the influence of gravity on the direction of flow, which may lead to an increase in intravascular pressure within the choroid located in the superior parts [36]. Additionally, the final stage of disc cup closing is located within the lower segments, which is also a common location of a choroidal coloboma, which may indicate a weaker vascularization of this choroidal region [36,37]. e above-mentioned causes may either make the inferior part of the perimacular region more susceptible to ischaemia or indicate different mechanisms of blood flow regulation.…”

Wide-Field Swept-Source Optical Coherence Tomography Analysis of Interocular Symmetry of Choroidal Thickness in Healthy Young Individuals

“…Choroidal thicknesses were measured with a caliper at 12 points as follows; 3 points at 900 μm, 1800 μm, and 2700 μm away from the Bruch's membrane opening (BMO) of nasal optic disc margin (nasal points 3, 2, and 1, respectively; nasal peripapillary area), 1 point at the subfovea, 6 points at 900 μm, 1800 μm, and 2700 μm away from the subfovea to nasal and temporal areas (nasal point 6 and temporal point 1; nasal point 5 and temporal point 2; nasal point 6 and temporal point 3, respectively; macular area), and 2 points at 2700 μm, 5400 μm away from temporal point 3 (temporal points 4, 5, respectively; peripheral area). Various studies have been conducted regarding peripheral retinal and choroidal morphology using wide-field OCT. [26][27][28] In most healthy individuals, both eyes are not anatomically and functionally identical, but they generally appear to be similar. If there is a change in interocular symmetry, the physician should consider whether it is due to disease or constitutes asymmetry within the normal range, as this can have an important effect on the determination of treatment.…”

Wide-field Swept-source OCT Analysis of Interocular Symmetry of Choroidal Thickness in Subjects with Uncomplicated Pachychoroid

“…The scan rate of commercially available SS-OCT is nearly twofold higher than that of conventional SD-OCT, thus reducing motion artifacts and enabling acquisition of wide-eld B-scan images. 18 A number of studies on peripheral retinal and choroidal morphology have been conducted using wide-eld OCT. [19][20][21] In most healthy individuals, both eyes are not anatomically or functionally identical, but have a generally similar appearance. Therefore, if there is a change in interocular symmetry, the physician should seek to determine whether it is due to disease or constitutes asymmetry within the normal range, as this has important implications for treatment planning.…”