Retinal angiography with real-time speckle variance optical coherence tomography

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• Retinal microvascular diseases pose a significant threat to vision worldwide.
• Accurate visualization of retinal capillary networks is crucial for diagnosis and management.
• Current imaging techniques have limitations in resolution and invasiveness.

Purpose of the Study:

• To introduce and evaluate a novel, non-invasive imaging technique: speckle variance optical coherence tomography (svOCT).
• To assess the capability of svOCT in visualizing human retinal capillary networks and blood flow.
• To compare the performance of svOCT with existing methods like fluorescein angiography.

Main Methods:

• Development of a custom-built swept source OCT system with a 100 kHz line rate.
• Implementation of real-time processing and visualization using a graphics processing unit (GPU).
• Comparison of svOCT imaging with fluorescein angiography in human capillary networks.

Main Results:

• svOCT demonstrated visibly greater capillary microvasculature density compared to fluorescein angiography.
• The technique generated en face images of capillary networks comparable to histological studies.
• svOCT successfully illustrated manifestations of diabetic retinopathy and retinal vascular occlusion non-invasively.

Conclusions:

• GPU-accelerated svOCT provides valuable quantitative information about retinal capillary networks.
• This non-invasive imaging modality shows significant potential for clinical and research applications in managing retinal microvascular diseases.
• svOCT offers a promising advancement in the diagnosis and monitoring of vision-threatening retinal conditions.