Pachychoroid Spectrum Disorders: An Updated Review

Abstract

Pachychoroid disease spectrum is a recent term that has been associated with an increasing number of phenotypes. This review discusses updated findings for each of the typical pachychoroid entities (central serous chorioretinopathy, pachychoroid pigment epitheliopathy, pachychoroid neovasculopathy, polypoidal choroidal vasculopathy, peripapillary pachychoroid syndrome, and focal choroidal excavation), as well as two relatively new additions (peripapillary pachychoroid neovasculopathy and peripheral exudative hemorrhagic chorioretinopathy). Here, we discuss the potential pathogenic mechanisms for these diseases and relevant imaging updates. Finally, we argue for a consistent classification scheme for these entities.

Keywords: Choroid; Pachychoroid; Focal Choroidal Excavation; Pachychoroid Neovasculopathy; Peripapillary Pachychoroid Neovasculopathy; Peripapillary Pachychoroid Syndrome; Polypoidal Choroidal Vasculopathy; Retinopathy; Central Serous Chorioretinopathy.

Figure 1

“Imaging of pachychoroid pigment epitheliopathy. (A) Multicolour image highlighting two small PEDs. (B) FAF imaging does not demonstrate major changes in RPE autofluorescence. (C) Near infrared image highlights the position of the line scan for the OCT in image D. Two elevated changes are again seen surrounded by haloes of reduced infrared signal. (D) EDI SD-OCT shows two small serous PEDs (arrowheads) with clear pachychoroid (arrow). PED, pigment epithelial detachment; FAF, fundus autofluorescence; OCT, optical coherence tomography; EDI SD-OCT enhanced depth imaging spectral domain-OCT” [included with permission from Wiley Publishing].^[1]

Figure 2

A 58-year-old female with PNV in the right eye. (A) FA demonstrating hyperfluorescence with minimal leakage. (B) OCT showing pigment epithelial detachment (PED) with hyperreflectivity within PED. (C) Early ICG which depicts dilated choroidal vessels and hyperfluorescence. (D) ICG late phase shows diffuse choroidal fluorescence with increasing hyperfluorescence at the lesion site.

Figure 3

Images of Pachychoroid Choroidal Vasculopathy in a 59-year-old male. (A) Color fundus imaging demonstrating a large, elevated subretinal hemorrhage involving majority of macula and extending to superior mid-periphery. (B) OCT imaging at case presentation. The patient underwent pars-plana vitrectomy, subretinal TPA, SF6, and Aflibercept injection. ICGA post-surgery, early (C) and late (D) stages, showed multiple focal leaks along with polypoidal network. OCT at this stage (E) showed subretinal fluid and pigment epithelial detachment. Subsequently, half-fluence PDT was performed, and complete regression of network was achieved, as shown on early (F) and late (G) phases of ICGA and no activity on OCT (H).

Figure 4

Images of Peripapillary Pachychoroid Syndrome in a 45-year-old male. OCT image (A) demonstrating peripapillary intra-retinal fluid accumulation, with minimal sub-retinal fluid. Fundus autofluorescence (B) shows hyper- and hypoautofluorescence changes along with retinal pigment epithelial tracts. Fluorescein angiography (C), and indocyanine green angiography (D) demonstrate choroidal vascular dilation, along with multiple areas of hyperfluorescence.

Figure 5

Optical coherence tomography of a 69-year-old male with CSCR demonstrating Focal Choroidal Excavation, along with intra-retinal fluid and an epiretinal membrane.

Figure 6

“Wide-field ICG angiogram of a 48-year-old with central serous chorioretinopathy. (A) Image obtained 2:51 min after indocyanine green dye injection. (B) Some of the intervortex venous anastomoses are highlighted in yellow for easier recognition. There are a group of vessels, highlighted in orange, that lead to the inferior macular region and are no longer visible in the central macula because of early leakage (area surrounded by orange outline). (C) Using wavelet contrast enhancement of the middle and low spatial frequency components, haze was removed from the image leaving clear delineation of the larger vessels. (D) The central intervortex venous anastomoses are visible, as highlighted in yellow” [included with permission from Elsevier.]^[8]