EyeWorld Asia-Pacific December 2020 Issue

NEWS & OPINION EWAP DECEMBER 2020 55 Contact information Cheung: gemmy.cheung.c.m@singhealth.com.sg Teo: kelvin.teo.y.c@singhealth.com.sg by Gemmy Cheung, MD, and Kevin Teo, MD Polypoidal Choroidal Vasculopathy: Consensus Nomenclature and Non-ICGA Diagnostic Criteria from the Asia-Pacific Ocular Imaging Society (APOIS) PCV Workgroup P olypoidal choroidal vasculopathy (PCV) is a subtype of neovascular age- related macular degeneration (nAMD) characterized by nodular dilatations arising from neovascular networks that ramify mainly in the subretinal pigment epithelial space. It affects about 50% of nAMD in Asian patients with a far lower prevalence reported in Caucasian populations. It is important to differentiate PCV from typical nAMD, especially with the use of vascular endothelial growth factor (VEGF) inhibitor monotherapy, as a significant proportion of patients with PCV do not respond well and may benefit from a change in their treatment strategy. Indocyanine green angiography (ICGA) is currently the only method to differentiate PCV from typical nAMD and remains the gold standard for the diagnosis of PCV. However, this imaging modalityis time- consuming, invasive, and may not be widely accessible to many clinicians, which may be one reason for the low reported prevalence of this entity. In contrast, optical coherence tomography (OCT) is widely available and almost ubiquitous in most ophthalmology practices. It is currently the mainstay imaging modality for the management of nAMD. In the context of PCV, several associations have been reported with specific OCT signs. With the shortcomings of ICGA, there remains an unmet need in the differentiation of PCV from typical nAMD without the use of ICGA. In this study we aimed to address this need by validating use of clinical examination and OCT, a widely used imaging modality, as a diagnostic tool for PCV. We gathered a group of international retina experts from the Asia-Pacific Ocular Imaging Society (APOIS) to, firstly, propose an updated consensus nomenclature for PCV andits associated phenotypic features. Secondly, the group assessed the diagnostic accuracy of a combination of signs on OCT and color fundus photographs (CFP) that may help differentiate PCV from typical nAMD. The key nomenclature recommendation from the workgroup was the use of the terms“polypoidal lesion” and “branching neovascular Figure 1. Reference images for the nine selected non-OCT features evaluated for inclusion into the final set of diagnostic criteria. Six features based on cross-sectional OCT are shown in a-f, one feature based on enface OCT (g) and two features based on fundus examination or color photography (h,i). (a) Sharp-peaked pigment epithelial de- tachment (PED), (b) sub-retinal pigment detachment ring-like lesion, (c) Complex/ Mul- tilobular PED, (arrow highlighting the notch within the outline of the PED) (d) Double layer sign/ Shallow irregular RPE elevation, (e) Thick choroid with dilated Haller’s layer vessels (scleral choroidal interface shown by arrowheads) (f) Predominance of subretinal fluid, (g) Complex RPE elevation observed with enface OCT (h) extensive subretinal hemorrhage, (i) orange nodule.