Endoscopic OCTA in continuous rotation and retraction scheme using a proximal scanning catheter

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Gastroenterology

Background:

• Endoscopic optical coherence tomography (OCT) provides high-resolution 3D imaging of internal tissues.
• Superficial capillary visualization via endoscopic OCT angiography (OCTA) is crucial for early lesion detection.
• Proximal catheter OCT systems offer advantages but face challenges in speed and stability for OCTA.

Purpose of the Study:

• To develop and validate an endoscopic OCTA system using a proximal scanning OCT.
• To overcome limitations of proximal scanning OCT for achieving stable and high-speed OCTA.
• To visualize microvascular alterations in luminal organs, particularly submucosal capillaries.

Main Methods:

• Endoscopic OCTA was implemented in a proximal scanning OCT system using a continuous rotation and retraction scheme.
• A decorrelation-based method was employed to analyze adjacent B-scan images for OCTA.
• A precision registration algorithm was developed to enhance OCTA image quality.
• Feasibility was validated using a microfluidic phantom and in vivo studies in rat rectums.

Main Results:

• The study successfully realized endoscopic OCTA in a proximally controlled OCT system.
• The developed system visualized intricate microvascular architecture, including submucosal capillaries.
• A continuous spiral B-scan rotation scheme enabled blood flow visualization in narrow lumen tissues.

Conclusions:

• This work presents the first implementation of endoscopic OCTA with a proximally controlled, continuously rotating OCT system.
• The developed technique facilitates detailed visualization of microvasculature in challenging luminal environments.
• This advancement holds potential for improved early diagnosis of diseases affecting internal organs.