Visualizing blood vessels in the human body in 3D without injections or radiation!

□ DGIST (President Kunwoo Lee) announced that a joint research team led by Professors Jaesok Yu, Hoejoon Kim, and Sanghoon Lee of the Department of Robotics and Mechatronics Engineering has developed an ultrasound imaging technology capable of clearly visualizing blood vessels deep inside the human body in three dimensions without having to use contrast agents. This technology is expected to significantly improve the safety and accessibility of medical imaging by enabling precise 3D blood flow images without radiation exposure or contrast agent injections.

□ Standard ultrasound exams mostly produce two-dimensional cross-sectional images, which makes it hard to see the full structure of organs or blood vessels. To visualize blood vessels in three dimensions, contrast agents or large equipment like CT or MRI are needed. However, contrast agents can cause side effects such as kidney damage and allergies, and they also add to examination costs and radiation exposure. Because of these issues, there is a strong demand for safe and easy-to-use 3D ultrasound technology.

□ Existing 3D ultrasound technologies have been limited by their complex sensor structure that uses thousands of transmit/receive channels, making the equipment bulky and expensive. To fix this, the DGIST research team introduced a ‘Row-Column Addressed Array (RCA)’ structure, which vastly reduces the number of channels. Although the RCA approach can simplify hardware, it decreases signal sensitivity and image quality. The team overcame these limitations by carefully optimizing the plane wave technique, which combines images from multiple angles, and adding ‘coded excitation’ technology, which encodes signals to boost their strength. This allowed them to successfully image blood vessels about 7 cm deep under the skin at high resolution, without using contrast agents.

□ The research team performed in vivo experiments on the liver and spleen of healthy adults, capturing blood flow in real time at 27 frames per second and achieving a contrast-to-noise ratio (CNR) improvement of about 9-10 dB compared to traditional imaging. Additionally, safety tests conducted according to US FDA and IEC standards confirmed that the probe kept a stable energy level without overheating during extended imaging.

□ Professor Jaesok Yu stated, "This study is a significant achievement that demonstrates the ability to observe blood vessels deep inside the human body in three dimensions without complex equipment or contrast agents. It can be immediately applied to the non-invasive diagnosis and monitoring of deep-seated organ diseases. Through DGIST's integrated research, we will develop this into a medical device that can be utilized in actual clinical settings."

□ This research was funded by the Excellent Young Researcher and Glocal Lab programs supported by the National Research Foundation of Korea (NRF), the Ministry of Science and ICT, and the Ministry of Education, as well as the DGIST R&D Program. The results were published online on September 17 in the renowned medical ultrasound journal 『Ultrasonics』.