Choroidal neovascularization fusion visualization for spectral-domain optical coherence tomography and optical coherence tomography angiography images.

PURPOSE: The spectral-domain optical coherence tomography (SD-OCT) images and OCT angiography (OCTA) images can provide complementary information for choroidal neovascularization (CNV) visualization. We expected to simultaneously display multifaceted characteristics of CNV in a single projection image.

METHODS

We proposed a fusion method for CNV visualization by combining structural and angiographic images, which mainly involves four steps: (a) Generate SD-OCT and OCTA projection images from original volumetric data with retinal layer restriction. (b) For SD-OCT projection images, enhance retinal vessels and CNV. (c) For OCTA images, detect CNV region based on multimodal data and display the neovascularization in false color. (d) A maximum fusion strategy was adopted to generate the fused images.

RESULTS

Experimental results with 30 cases from 30 patients demonstrate that the fused images are more effective in displaying CNV than single-modality projection images. The average information entropy and the mean gradient in the CNV regions for SD-OCT projection images, OCTA images, and the fusion images are 4.66/0.21, 5.45/0.45, and 6.8/0.58, respectively.

CONCLUSIONS

The proposed method is more effective for CNV visualization than the conventional single-modality image-based method. The proposed method can combine complementary information from multimodal images and provide a satisfying visual effect.