NTU HIGHLIGHTS August 2014  
  Research Achievements  
Advanced Noninvasive Optical Probe Provides Subcellular 3D Images of Human Skin Cells

Working under a photonics subproject led by Prof. Hung-Chun Chang of the Center for Information and Electronics Technologies (CIET), Prof. Sheng-Lung Huang of the Graduate Institute of Photonics and Optoelectronics and Prof. Jeng-Wei Tjiu of NTU Hospital have developed a state-of-the-art optical coherence tomography (OTC) system to image human skin and cancer cells for both morphological recognition as well as parametric analysis.

The OCT system provides a three-dimensional in vivo cellular-resolution imaging that is capable of revealing subcellular structures (i.e., the nucleus). The system’s high resolution enables the separation of the lamellar structure of the full epidermis in both cross-sectional and en face planes. It is believed that imaging modalities, such as this one, serve as one of the keys to early-stage detection of disease and cancer.

Prof. Huang and Prof. Tjiu have demonstrated the powerful imaging capabilities of their system by measuring the number as well as thickness of the stratum corneum’s layers. Additionally, the optical probe is noninvasive and label-free, making it ideal for clinical applications.

With the OCT, the researchers also conducted an in vivo experiment in which they observed micro blood vessels in dermis and traced the flowing of red blood cells in real time. They have also developed image analysis algorithms that automatically extract diagnostic information from live tissue and single cells.

The team was able to achieve such high-resolution, high-speed live human skin imaging capabilities through its invention of the powerful, crystalline fiber-based broadband and high-brightness light sources. This patented technology can generate wavelength ranges from 400 nm to 1.6 μm with 3-dB bandwidths from 100 to 250 nm.

Aiming to further realize the exciting clinical applications of their advanced imaging modality, the CIET team has initiated an interdisciplinary research project with an NTU Hospital colorectal cancer research team led by Prof. Chia-Tung Shun. Funded by the National Research Program for Biopharmaceuticals, the project intends to bring this technology into clinical practice through the validation of optical biopsy histopathologically. As a result of the collaboration, the CIET team has developed a new OCT prototype that will serve as a test bed for histology comparison.

Prof. Huang and Prof. Tjiu are currently working to enhance the OCT system's sensitivity and specificity, provide real-time data transmission and storage, and enable the patient’s pathological information to be linked to the treating physician’s diagnosis. The goal is to eventually offer a see-and-treat paradigm that will lead to improvements in patient care and reductions in medical costs.