Comprehensive vascular imaging using optical coherence tomography-based angiography and photoacoustic tomography

Area of Science:

• Biomedical Optics
• Dermatology
• Medical Imaging

Background:

• Cutaneous vasculature abnormalities are linked to various dermatological disorders.
• Noninvasive in vivo imaging of skin vasculature is crucial for diagnosis and monitoring.
• Advanced optical imaging techniques are needed to overcome limitations of existing methods.

Purpose of the Study:

• To evaluate the complementary capabilities of photoacoustic tomography (PAT) and optical coherence tomography with angiography extension (OCTA) for imaging human skin vasculature in vivo.
• To demonstrate the combined potential of PAT and OCTA for visualizing both superficial capillaries and deeper vessels.

Main Methods:

• Utilized photoacoustic tomography (PAT) and optical coherence tomography with angiography extension (OCTA) to image the palm of a healthy volunteer and three subjects with cutaneous abnormalities.
• Compared the visualization capabilities and effective imaging depth ranges of PAT and OCTA.

Main Results:

• OCTA successfully visualized capillaries in the papillary dermis, which were too small to be discerned by PAT.
• PAT provided images of deeper vessels, complementing OCTA's superficial imaging.
• Speculated that photoacoustic signals in volar skin primarily originate from hemoglobin in capillaries due to low melanin concentration.

Conclusions:

• PAT and OCTA offer complementary imaging capabilities for human skin vasculature in vivo.
• The combined approach demonstrates effective visualization across different depths, aiding in the study of skin conditions.
• This integrated imaging system holds promise for improved treatment monitoring of dermatological diseases linked to vascular abnormalities.