Visualising the choriocapillaris: Histology, imaging modalities and clinical research ‐ A review

• Published in: Clinical & experimental ophthalmology Vol. 50; no. 1; pp. 91 - 103
• Main Authors: Ng, Danny Siu‐Chun, Chan, Leo Ka‐Yu, Ng, Ching Man, Lai, Timothy Y. Y.
• Format: Journal Article
• Language: English
• Published: Melbourne John Wiley & Sons Australia, Ltd 01.01.2022; Wiley Subscription Services, Inc
• Subjects: Aging; Angiography; Central Serous Chorioretinopathy; choriocapillaris; Choroid - blood supply; choroidal imaging; Diabetes mellitus; Diabetic retinopathy; Diabetic Retinopathy - pathology; Female; Fluorescein Angiography - methods; Histology; Humans; Macular degeneration; Medical imaging; Microvasculature; Myopia; optical coherence tomography angiography; Pregnancy; Pregnancy complications; Retinal Vessels - pathology; Retinopathy; Tomography, Optical Coherence - methods; Uveitis; Vascular diseases; optical coherence tomography angiography; choriocapillaris; choroidal imaging
• DOI: 10.1111/ceo.13984
• ISSN: 1442-6404

The choriocapillaris plays a considerable role in the normal physiology of the eye as well as in various diseases. Assessing the changes in the choriocapillaris can therefore provide important information about normal ageing and pathogenesis of visual impairment, and even some systemic diseases. In vivo imaging of the choriocapillaris has evolved from non‐depth resolved, dye‐based angiography to advanced, high‐resolution optical coherence tomography angiography (OCTA). However, the intricate microvascular networks within the choriocapillaris are still beyond the resolving limits of most OCTA instruments. Knowledge of histology, meticulous image acquisition methods, recognition of artefact and post‐acquisition processing techniques are necessary for optimising OCTA choriocapillaris images. Qualitative and quantitative analyses of the choriocapillaris provide clinical information in age‐related macular degeneration (AMD), diabetic retinopathy (DR), pathologic myopia and central serous chorioretinopathy (CSC). Furthermore, studies have revealed choriocapillaris changes in posterior uveitis that are correlated with treatment outcome and have important prognostic significance. In addition to retinal diseases, choriocapillaris changes have been observed in systemic vascular diseases and complications associated with pregnancy.