Multimodality endoscopic imaging technology for visualization of layered architecture and vasculature

Endoscopic imaging technologies, such as endoscopic optical coherence tomography (OCT), near infrared (NIR) fluorescence, photoacoustic (PA), and ultrasound (US) have been used to investigate vascular and morphological changes as hallmarks of early cancer in the gastrointestinal (GI) tract. Here, we developed two multimodality imaging systems which are integrated PA/US and integrated OCT/NIR fluorescence which can obtain layered architecture and vasculature simultaneously. In vivo imaging of rectum wall from Sprague Dawley (SD) rats with these two imaging systems were demonstrated. Both imaging systems enable the use of one imaging probe for performing two different imaging, thereby improving prognosis by early detection and reducing costs. For integrated PA/US, the architectural morphology and vasculature of the rectum wall were visualized without the usage of contrast agent, but slow imaging speed and usage of match medium are the main limitations for clinical translation. With regard to the integrated OCT/NIR fluorescence, it is able to perform high speed imaging, however the addition of contrast agent and limited imaging depth are the main concern for clinical application.