Choroidal Thickness Profile in Chorioretinal Diseases: Beyond the Macula

Abstract

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.

Macular choroidal thickness and correlations in a healthy pediatric South Asian cohort: A spectral domain optical coherence tomography study

“…Automated solutions have been suggested to lessen the inaccuracy of subjective disparities present in the procedures [40,41]. The importance of measurement of ChT has been emphasized in the study of chorioretinal diseases, where choroidal dysfunction plays an important role in their pathogenesis, namely central serous retinopathy, polypoidal choroidal vasculopathy, age-related macular degeneration, retinal vascular diseases, retinitis pigmentosa, glaucoma, and uveitis [42][43][44]. The advent of OCT has provided us with a tool to directly image and measure the ChT and volume to better understand pathogenic mechanisms of ocular and metabolic, inflammatory, neurodegenerative, and metabolic systemic diseases affecting the choroid [44][45][46][47].…”

Characteristics of the peripapillary structure and vasculature in patients with myopic anisometropia

“…Moreover, SS-OCT reduces motion artifacts and permits high-speed, high-resolution imaging and better visualization of the ONH. (23,24,41) In addition, SS-OCT showed excellent repeatability and reproducibility in ONH parameters. (42) Therefore, the current study used SS-OCT to analyze ONH characteristics in myopic anisometropia.…”

“…The choroid is one of the most vascularized structures in the human body, supplying most of the blood, nutrients, and oxygen to the retina. (14,24,51) More evidence has shown two other functions of the choroid: adjusting the position of the retina by changing the CT and releasing growth factors to regulate the modulation of vascularization and scleral remodeling, as well as promoting ocular growth. (52,53) Variations in CT may be predominantly driven by changes in choroidal blood ow, given that the choroid is essentially a vascular structure capable of quickly altering blood ow.…”

“…(11,13,(19)(20)(21)(22) However, the characteristics of ONH in myopic asymmetrical ocular growth remain unknown. (23)(24)(25)(26)(27) With the advent of swept-source optical coherence tomography (SS-OCT) technology, visualization of a larger area with reduced motion artifact and better visualization of the choroidal vasculature system is possible. ( 23) SS-OCT has been widely applied in studies on myopia and ocular diseases centered on the fovea.…”

Evaluation of choroidal thickness in non-alcoholic fatty liver disease

“…[10] In fact, these breakthroughs have augmented our insight of choroidal changes in various systemic diseases especially those related with a disrupt vascular state. [11] Loureiro et.al found that choroidal thickness (CT) in temporal and inferotemporal sectors were signi cantly lower in MetS patients. [12] Factors pertinent to NAFLD including obesity, [13,14] cardiovascular risk factors [15] and insulin resistance [16] have also proven to be negatively correlated with CT.…”