Optical Coherence Tomography (OCT) biomarkers in naïve classic choroidal neovascular membranes (CNV) correlate strongly with fundus fluorescin angiography (FFA) findings.

Abstract

Purpose : OCT scans are frequently used in the diagnosis of new choroidal neovascularization membranes and are increasingly being used to aid with FFA investigations, as they are less invasive. There have been very few studies looking at specificity and sensitivity of OCT vs FFA in the diagnosis of naïve CNV. However, none of them have successfully established a correlation between the two imaging modalities and disease pathology. As such, this study aims to quantitatively assess the correlation between two imaging modalities in patients with naïve classic CNV.

Methods : Retrospective analysis of images of patients (n=63)who had OCT and FFA confirmed naïve CNV was performed. The OCT images taken with Heidelberg Spectralis at diagnosis were compared to the FFA images obtained on the same day. The subretinal hyperreflective mass (SRHRM) was used as the OCT biomarker. The size of this subretinal hyperreflective lesion was quantitatively measured at it’s widest using calipre setting. This was then compared to the widest diameter of the CNV lesion measured on ultra high resolution Spectralis FFA.

Results : Images of both OCT and FFA for 63 patients were analysed. The relationship between the OCT measurement of the CNV and the FFA leakage was analysed using the regression coefficient. The correlation between the OCT and FFA lesion size was found to have a linear relationship whereby the OCT measurement could be predicted with the equation y=0.8551x +483.94, where y is the OCT lesion size and x is the size of FFA leakage lesion. The coefficient determinant R² was found to be 0.834 (p<0.001)

Conclusions : This study shows that there was a strong correlation between the size of the OCT biomarker and the size of the active lesion on FFA. OCT was found to overestimate the size of the active lesion by approximately 483 microns. However, it is still an extremely useful tool in the diagnosis of active lesions. This results show us that we are able reasonably predict the size of the active lesion from the OCT biomarker, as such, this could be used to influence management decisions without angiography, if necessary.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.