Polypoidal choroidal vasculopathy - is indocyanine green angiography essential for diagnosis?

Abstract

Purpose: To determine the sensitivity and specificity for polypoidal choroidal vasculopathy (PCV) diagnosis without accessing indocyanine-green angiography (ICGA) images. To establish the main optical coherence tomography (OCT) features related with providing a correct diagnosis.

Methods: Local database was accessed by one of the authors, who identified consecutive patients with newly diagnosed PCV or occult choroidal neovascularization (CNV). All medical records were then reviewed and only patients without previous ocular treatments, which had baseline color fundus photographs, OCT, fluorescein angiography (FA) and ICGA images were included. PCV diagnosis was assumed when PCV lesions were identifiable on ICGA. Baseline images were collected and organized by patient, blinding any identifying features. Thereafter, all but ICGA were provided to three other Ophthalmologists. Images’ evaluation was performed independently by each one, according to a standardized database.

Results: One-hundred eyes were included, 53 occult CNV and 47 PCV. 29% had available Spectralis® HRA+OCT, the remaining Cirrus® HD-OCT. Considering diagnosis by graders when at least 2 of them agreed, 32 of the 47 PCV were identified, representing a sensitivity of 68.09% (95% CI 55.88; 80.91) and a specificity of 56.60% (95% CI 42.28; 70.16). Regarding individual results, sensitivity and specificity significantly varied with grader’s experience. The availability of Spectralis® OCT was significantly associated with a higher rate of correct diagnosis (p=0.010). The OCT findings which were most significantly associated with provide a correct PCV diagnosis were the identification of subfoveal (p=0.050) and extrafoveal polypoidal lesions (p=0.001) and of a notch at the margin of serous retinal pigment epithelium detachment (p=0.034). When they were identified, graders always provided a correct diagnosis (positive predictive value of 100% for all).

Conclusions: To our knowledge, this was the first study which evaluated the accuracy of PCV diagnosis without the concomitant use of ICGA. It revealed a good sensitivity and specificity. The graders' experience and the type of available OCT seem to be a determinant factor. Doctors should be trained to identify the OCT features with the higher positive predictive rates.

Keywords: 412 age-related macular degeneration • 550 imaging/image analysis: clinical