Evaluation of Peripapillary and Subfoveal Choroid Thickness in Asymptomatic Carotid Artery Stenosis

Quantitative assessment of retinochoroidal microvasculature in patients with carotid artery stenosis using OCT angiography

PURPOSE

To investigate the alterations in retinochoroidal parameters measured by optical coherence tomography (OCT) and OCT angiography (OCTA) in patients with carotid artery stenosis (CAS) and assess their associations with digital subtraction angiography (DSA) data.

METHOD

This study enrolled patients diagnosed with CAS and age-matched healthy controls. Both groups underwent OCT and OCTA examinations. DSA and assessment of carotid artery stenosis were performed only in the CAS group. The study evaluated various retinochoroidal parameters from OCT and OCTA, including linear vessel density (LVD), foveal avascular zone (FAZ), choroidal thickness (ChT), and retinal nerve fiber layer (RNFL) thickness. DSA-derived measures included cervical segment (C1) diameter, cavernous segment (C4) diameter, stenosis percentage, ophthalmic artery (OA) filling time, C1-OA filling time, and residual stenosis.

RESULTS

A total of 42 eyes from 30 CAS patients and 60 eyes from 30 healthy controls were included. Patients with CAS displayed significantly decreased LVD compared to controls (p < 0.001). Additionally, the CAS group had thinner choroid and RNFL (p = 0.047 and p < 0.001, respectively). Macular LVD negatively correlated with both stenosis percentage and C1-OA filling time (p = 0.010 and p = 0.014, respectively). In patients who underwent carotid artery stenting, preoperative ChT significantly correlated with residual stenosis (Pearson r = -0.480, p = 0.020).

CONCLUSION

OCT and OCTA provide a quantitative assessment of retinochoroidal microstructural changes associated with CAS, suggesting potential for noninvasive evaluation of the disease. This might contribute to the prevention of irreversible ocular complications and early detection of CAS. Furthermore, ChT may not only aid in diagnosing CAS more reliably but also offer prognostic information.

The clinical implications of choroidal thickness combined with tear VEGFA in coronary artery disease

OBJECTIVE

The purpose of this study was to evaluate the effect of choroidal thickness and tear vascular endothelial growth factor A (VEGFA) as biomarkers of coronary artery disease (CAD).

METHODS

This study was a retrospective observational case-control trial. A total of 637 patients who underwent coronary angiography to assess their coronary artery status were included. The patients were divided into two groups: 200 people in the No CAD group and 437 people in the CAD group. We evaluated the choroidal thickness of the right foveal membrane in all patients through optical coherence tomography angiography examination. We also collected tear samples from patients to measure VEGFA. The ROC curve and its area under the curve (AUC) were used for analysis.

RESULTS

The central foveal choroid in the No CAD group was significantly thicker than that in the CAD group (289.09 μm ± 38.41; 229.03 μm ± 33.44, P  < 0.01). The tear VEGFA in the CAD group was higher than that in the No CAD group (706.15 ng/mL ± 147.42; 419.66 ng/mL ± 105.85, P  < 0.01). Spearman analysis showed that the correlation between choroidal thickness and Gensini score was -0.7387 ( P  < 0.01). The correlation between tear VEGFA level and Gensini score was 0.8636 ( P  < 0.01). Taking choroidal thickness and tear VEGFA as independent variables, we obtained AUC = 0.9647 (95% CI 0.9506-0.9789, P  < 0.01) through binary logic regression and ROC curve analysis.

CONCLUSION

The combination of choroidal thickness and tear VEGFA in patients can serve as a clinical marker of CAD and its severity.

Impaired retinal microcirculation in patients with non-obstructive coronary artery disease

PURPOSE

To quantitatively investigate alterations of retinal microcirculation in patients with non-obstructive coronary artery disease (NOCAD) using optical coherence tomography angiography (OCTA), and to identify the ability of retinal microcirculation parameters in differentiating coronary artery disease (CAD) subtypes.

METHODS

All participants with angina pectoris underwent coronary computed tomography angiography. Patients with lumen diameter reduction of 20-50 % in all major coronary arteries were defined as NOCAD, while patients with at least one major coronary artery lumen diameter reduction ≥ 50 % were recruited as obstructive coronary artery disease (OCAD). Participants without a history of ophthalmic or systemic vascular disease were recruited as healthy controls. Retinal neural-vasculature was measured quantitatively by OCTA, including peripapillary retinal nerve fiber layer (RNFL) thickness and vessel density (VD) of the optic disc, superficial vessel plexus (SVP), deep vessel plexus (DVP), and foveal density (FD 300). p < 0.017 is considered significant in multiple comparisons.

RESULTS

A total of 185 participants (65 NOCAD, 62 OCAD, and 58 controls) were enrolled. Except for the DVP fovea (p = 0.069), significantly reduced VD in all other regions of SVP and DVP was detected in both the NOCAD and OCAD groups compared to control group (all p < 0.017), while a more significant decrease was found in OCAD compared to NOCAD. Multivariate regression analysis showed that lower VD in superior hemi part of whole SVP (OR: 0.582, 95 % CI: 0.451-0.752) was an independent risk factor for NOCAD compared to controls, while lower VD in the whole SVP (OR: 0.550, 95 % CI: 0.421-0.719) was an independent risk factor for OCAD compared to NOCAD. Using the integration of retinal microvascular parameters, the area under the receiver operating characteristic curve (AUC) for NOCAD versus control and OCAD versus NOCAD were 0.840 and 0.830, respectively.

CONCLUSION

Significant retinal microcirculation impairment, while milder than that in OCAD was observed in NOCAD patients, indicating retinal microvasculature assessment might provide a new systemic microcirculation observation window for NOCAD. Furthermore, retinal microvasculature may serve as a new indicator to assess the severity of CAD with good performance of retinal microvascular parameters in identifying different CAD subtypes.

Choroidal Thickness Profile in Chorioretinal Diseases: Beyond the Macula

Enhanced depth imaging optical coherence tomography (EDI-OCT) and swept-source OCT (SS-OCT) have emerged as essential diagnostic tools in the study and management of various chorioretinal diseases. Evidence from early clinical studies using EDI-OCT and SS-OCT indicates that choroidal dysfunction plays a major role in the pathogenesis of chorioretinal diseases. Measurement of choroidal thickness (CT) has already become a major research and clinical method, and CT is considered as an indicator of choroidal status in a variety of ophthalmic diseases. Recently, CT measurement has also been proposed as a non-invasive marker for the early detection and monitoring of various systemic diseases. Among the several possible CT measurement locations, subfoveal CT has rapidly become a reliable parameter for measuring CT in healthy and diseased eyes. Moreover, recent advancements in OCT technology have enabled faster and wider imaging of the posterior part of the eye, allowing the various changes in CT as measured outside the macula to be shown accordingly. In this review, we first provide an overview of the results of clinical studies that have analyzed the healthy macular choroid and that in various chorioretinal diseases, and then summarize the current understanding of the choroid outside the macula. We also examine the CT profile as an index that encompasses both within and outside of the macula. Furthermore, we describe the clinical applications of ultrawide OCT, which enables visualization of the far periphery, and discuss the prospects for the development of more reliable choroidal parameters that can better reflect the choroid's characteristics.