Automated vessel diameter quantification and vessel tracing for OCT angiography

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Ophthalmology

Background:

• Optical coherence tomography angiography (OCTA) enables non-invasive in vivo imaging of vascular networks.
• Advancements in OCTA image quality allow for extraction of vascular parameters for disease diagnosis and treatment.

Purpose of the Study:

• To present an automated method for mapping vessel diameter down to the capillary level using OCTA.
• To validate the technique in vitro and in vivo for enhanced vascular analysis.

Main Methods:

• Gradient-guided minimum radial distance (MRD) for automated vessel diameter mapping.
• Modified A* path searching algorithm for tracing vessel branches and calculating diameters.
• Validation using microfluidic flow phantoms and in vivo mouse cortical vasculature.

Main Results:

• MRD method showed superior consistency and reduced error compared to existing techniques.
• The algorithm successfully traced vessel branches and calculated diameters, adhering to Murray's law down to the capillary level.
• Vessel tortuosity and branching angles were measurable, aligning with physiological data.

Conclusions:

• The developed automated techniques provide a platform for comprehensive vascular evaluation using OCTA.
• This method may aid in the early diagnosis of vascular diseases, particularly those with subtle morphological changes.