High-resolution rectoscopy using MHz optical coherence tomography: a step towards real time 3D endoscopy.

Area of Science:

• Gastroenterology and Medical Imaging
• Biomedical Engineering
• Optical Coherence Tomography

Background:

• Colonoscopy and endoscopic ultrasound are key for rectal disease assessment, including cancer and inflammatory bowel disease.
• Optical Coherence Tomography (OCT) provides superior depth resolution crucial for treatment planning and response evaluation.

Purpose of the Study:

• To develop and evaluate novel rectoscope prototypes integrated with a 1300 nm MHz-OCT system for enhanced rectal imaging.
• To assess the real-time endoscopic imaging capabilities of the OCT-rectoscope for visualizing rectal structures and pathologies.

Main Methods:

• Development of two distinct rectoscope prototypes integrated into a custom-built 1300 nm MHz-OCT system.
• High-speed rotational scanning (40,000 rpm) enabling a 667 Hz OCT frame rate for real-time imaging.
• Ex vivo porcine colon and post mortem human in-situ colon assessment, followed by histological confirmation.

Main Results:

• The OCT-rectoscope successfully distinguished intestinal wall layers and identified gut-associated lymphatic tissue.
• Real-time 3D visualization and reconstruction of a rectal polyp were achieved.
• Histological examination confirmed the OCT findings, demonstrating accurate discrimination of rectal wall layers and tissue characteristics.

Conclusions:

• The developed MHz-OCT-rectoscope effectively visualizes rectal wall layers and tissue characteristics in real-time 3D.
• This technology shows significant potential as a future diagnostic tool for on-site assessment of rectal diseases and therapy response.
• The system's ability to provide high-resolution, real-time imaging could improve individualized therapeutic strategies.