Morphologic Characteristics of Choroid in the Major Choroidal Thickening Diseases, Studied by Optical Coherence Tomography.

Hoyoung Lee,Gyule Han,Na-Kyung Ryoo,Kunho Bae,Se Joon Woo,Se Woong Kang,Sang Jin Kim,Toshiaki Abe

doi:10.1371/journal.pone.0147139

Abstract

We investigated morphologic features of choroid in the choroidal thickening diseases, including central serous chorioretinopathy (CSC), polypoidal choroidal vasculopathy (PCV), and Vogt-Koyanagi-Harada disease (VKH), by a novel tomographic classification system of the choroid. This cross-sectional study involved 30 patients with active CSC, 30 patients with active PCV, and 27 patients with active VKH, and 30 normal controls. Utilizing enhanced depth imaging optical coherence tomography, we classified the morphology of the choroid into five categories: 1) Standard (S), 2) Dilated outer layer and Attenuated inner layer (DA), 3) Darkened (D), 4) Marbled (M), and 5) Pauci-Vascular (PV) types. Additional tomographic characteristics of the choroid such as choroidal vascular dilation, convolution, scleral invisibility, and choroidal hyper- or hypo-thickening were identified as well. The distribution of five choroidal tomographic morphology and additional tomographic characteristics in each group were analyzed. The DA type was observed in the CSC group more frequently than in the normal control group (53.3% vs 3.3%, P < 0.001). Additional tomographic characteristics, such as choroidal vascular dilation (76.7%), and choroidal hyper-thickening (36.7%), were more prevalent in the CSC group than in the control group. The PCV group showed higher prevalence of DA type (33.3% vs. 3.3%, P = 0.006) than the control group. The VKH group showed a significantly higher frequency of the D type (63.0%), convolution (40.7%), and scleral invisibility (70.4%) than controls (0% for all three findings). In conclusion, CSC and PCV shared common morphologic characteristics of choroid, including dilated outer vascular layer and focally attenuated innermost layer. Dense hypo-reflectivity and convolution of choroid were the specific tomographic markers for acute VKH. A new tomographic classification system of choroid may provide discrimination ability and insight into major pachychoroidopathies.

Highlights

The recent advent of tomographic imaging techniques of deeper layers, such as enhanced depth imaging optical coherence tomography (EDI-OCT) or swept source OCT, has enabled in-vivo cross-sectional imaging of the choroid [1,2,3,4,5,6]
The purpose of this study is to identify the morphologic characteristics of the major pachychoroidopathies (CSC, polypoidal choroidal vasculopathy (PCV), and Vogt-Koyanagi-Harada disease (VKH)) by applying a novel tomographic classification system of the choroid
Eighty percent of the PCV group was classified as either S type (46.7%) or DA type (33.3%), and 85.2% of the VKH group was classified as either D type (63.0%) or M type (22.2%)

Summary

Introduction

The recent advent of tomographic imaging techniques of deeper layers, such as enhanced depth imaging optical coherence tomography (EDI-OCT) or swept source OCT, has enabled in-vivo cross-sectional imaging of the choroid [1,2,3,4,5,6]. Understanding of such tomography is essential for understanding the structure of the normal choroid and for identifying structural changes in diseases that affect the choroid. The purpose of this study is to identify the morphologic characteristics of the major pachychoroidopathies (CSC, PCV, and VKH) by applying a novel tomographic classification system of the choroid

Objectives

Methods

Results

Conclusion