Biomicroscopic System Could Yield More Effective Cancer Treatment

A multimodal biomicroscope based on high-frequency ultrasound and optical spectroscopy could overcome the challenges of existing imaging systems for tumor analysis and provide physicians with the means to avoid unwanted outcomes such as cancer recurrence or metastasis to other organs.

For examining tumors resected during surgery with high levels of accuracy, researchers at Daegu Gyeongbuk Institute of Science and Technology (DGIST) have devised a biomicroscopic system that converges multispectral imaging, high-frequency B-mode and ARFI techniques. The system can perform pathologic analysis simultaneously to detect tumors deep within the tissues during the cancer operation.

This is a conceptual diagram showing characteristics of Multimodal Biomicroscopic System. Courtesy of Daegu Gyeongbuk Institute of Science and Technology (DGIST).

To evaluate the system, the team examined nine tissue-mimicking phantoms with different mechanical properties. It also investigated whether the system would differentiate colorectal tumors from normal regions in the tumor regions resected from six cancer patients.

Experimental results showed that the multimodal biomicroscopic system enabled mechanical, chemical and structural analysis of the tumor tissue from colon cancer patients at high resolution. This allowed the detection of tumor regions from the surface to deep inside tissues.

According to researchers, this is the first system to use multiple imaging modalities simultaneously to obtain different yet complementary information about excised tumors from the surface to areas deep inside the tissue.

The researchers believe that tissue and tumor areas can be analyzed more precisely with their system than with a general fluorescence microscope, as their optical spectroscopic imaging technique quantitatively analyzes the spectroscopic indicators emitted from the tissue surface. It is possible to detect deep tissue as well as tumor areas with a high degree of accuracy because the system’s High Frequency Ultrasonic B-mode and High Frequency Ultrasonic Radiation Force Imaging modalities can image the impedance and elasticity of the tissue at higher resolution than existing ultrasonic imaging techniques.

“We have developed a multimodal biomicroscopic system based on high-frequency ultrasound and optical spectroscopy for the first time in the world," professor Jaeyoun Hwang said. "It complements the disadvantages of the existing image analysis systems. We will conduct further studies to develop this system to the endoscope system which can be used for clinical diagnosis of cancer before the actual surgery.”

The multimodal biomicroscopic system could improve the efficiency and success rate of cancer surgery by increasing the accuracy of tumor removal surgery as well as shortening operating time. The study shows that the multimodal biomicroscopic system has the potential to rapidly characterize excised human tissues qualitatively through a combination of high-frequency ultrasound and optical imaging modalities, compared to the conventional histopathological examination. Thus, it could become a very advantageous biomedical tool for use during surgical operations.

The research was published in Scientific Reports (doi:10.1038/s41598-017-17367-1).