High-contrast abnormal vasculature imaging of exudative macular disease by using multi-contrast optical coherence tomography

Abstract

 

Purpose

 

Optical coherence angiography technique non-invasively visualizes the three-dimensional microvasculature of the posterior eye by detecting the motion of blood cells. In the current techniques, low intensity of optical coherence tomography (OCT) image causes artifacts in blood flow detection and disturb the contrast of vasculature. In this presentation, an improved OCT based angiography for abnormal vasculature imaging is demonstrated. This method is based on high-contrast correlation mapping technique and is immune to the ill effect of low OCT signal intensity.

 

Methods

 

Retinas of subjects were scanned with 1-μm high-penetration Jones matrix optical coherence tomography (JM-OCT). It is operated at 100,000 axial scanning rate. Six eyes of 6 subjects have been examined, which include 2 age-related macular degeneration (AMD), 1 neovascular maculopathy, 3 polypoidal choroidal vasculopathy (PCV). One AMD and 1 PCV eyes were scanned twice before and after anti-VEGF injections. A newly developed high-contrast correlation mapping algorithm was used to visualize three-dimensional microvasculature. The abnormal vasculature in exudation are subjectively investigated.

 

Results

 

The representative high contrast OCT based angiography is shown in Fig. 1. The subject is left eye of an AMD patient (79 yo). Comparing to fluorescence angiographies, better visualization of abnormal vasculature is obtained. In cross-sectional image (Fig. 2), it is found that the several abnormal vessels are located in exudative lesion. In the all patient (6/6 eyes), abnormal vasculature are observed at exudative lesion. Although the signal of abnormal vasculature were significantly decreased after anti-VEGF injections, still abnormal blood flow signals have been observed at small exudation in all eyes (2/2).

 

Conclusions

 

The OCT vasculature imaging by using high-contrast correlation mapping technique exhibits excellent performance to visualize abnormal vasculature non-invasively. This technique might be powerful tool to detect and investigate vascular diseases of the posterior eye.  

 

Fig. 1 En-face vasculature images of AMD patient: (a) OCT angiography with high-contrast correlation mapping technique, (b) Fluorescein and (c) Indocyanine green angiography. The yellow line indicate the location of cross sections (Fig. 2).

 

 

Fig. 2 Cross-sectional images of (a) OCT and (b) high-contrast correlation mapping.