Medical Lasers; Engineering, Basic Research, and Clinical Application  
Optical Imaging Technology for Real-time Tumor Monitoring
Yoo-kyoung Shin, Joo Beom Eom
Department of Biomedical Science, College of Medicine, Dankook University, Cheonan, Korea
Correspondence to: Joo Beom Eom
Department of Biomedical Science, College of Medicine, Dankook University, 119 Dandae-ro, Dongnam-gu, Cheonan 31116, Korea
Tel.: +82-41-550-3275
Fax: +82-41-550-3275
Received: July 20, 2021; Accepted: August 11, 2021; Published online: September 9, 2021.
© Korean Society for Laser Medicine and Surgery. All rights reserved.

Optical imaging modalities with properties of real-time, non-invasive, in vivo, and high resolution for image-guided surgery have been widely studied. In this review, we introduce two optical imaging systems, that could be the core of image-guided surgery and introduce the system configuration, implementation, and operation methods. First, we introduce the optical coherence tomography (OCT) system implemented by our research group. This system is implemented based on a swept-source, and the system has an axial resolution of 11 µm and a lateral resolution of 22 µm. Second, we introduce a fluorescence imaging system. The fluorescence imaging system was implemented based on the absorption and fluorescence wavelength of indocyanine green (ICG), with a light-emitting diode (LED) light source. To confirm the performance of the two imaging systems, human malignant melanoma cells were injected into BALB/c nude mice to create a xenograft model and using this, OCT images of cancer and pathological slide images were compared. In addition, in a mouse model, an intravenous injection of indocyanine green was used with a fluorescence imaging system to detect real-time images moving along blood vessels and to detect sentinel lymph nodes, which could be very important for cancer staging. Finally, polarization-sensitive OCT to find the boundaries of cancer in real-time and real-time image-guided surgery using a developed contrast agent and fluorescence imaging system were introduced.
Keywords: Optical imaging; Optical coherence tomography; Near-infrared fluore-scence; Indocyanine green; Cancer

This Article