A research team at Pohang University of Science and Technology (POSTECH) has delved into the study of kidney diseases using an innovative ultrafast ultrasound technique capable of capturing 1,000 images in just one second.
This breakthrough research, published in Advanced Science, focuses on imaging the three-dimensional microvasculature of the kidneys without the need for contrast agents, garnering attention for its potential impact on understanding and diagnosing kidney-related conditions.
The kidneys play a crucial role in filtering waste and eliminating unwanted substances from the bloodstream. Conditions such as hypertension and diabetes can compromise the kidney’s vital function, leading to irreversible kidney failure. The standard treatment for this condition involves lifelong artificial hemodialysis or kidney transplantation.
Microvascular imaging, which provides insights into blood perfusion in the kidneys, can be a pivotal indicator for both preventing and recovering from kidney failure. Traditional medical imaging methods, such as computed tomography (CT) and magnetic resonance imaging (MRI), have limitations in capturing fine vascular structures due to resolution and sensitivity constraints. Additionally, the use of contrast agents in these methods is restricted due to potential side effects in patients with kidney disease.
In contrast, ultrasound imaging, known for its safety in fetal monitoring, utilizes the Doppler effect to measure real-time blood flow velocity and direction without requiring contrast agents. However, the existing ultrasound imaging speed has limitations in capturing fine blood vessels with sufficient sensitivity.
The research team at POSTECH addressed this challenge by enhancing microvascular sensitivity through ultrafast ultrasound acquisition, achieving a speed over 100 times faster than conventional ultrasound imaging, capturing 1,000 frames per second.
Using this cutting-edge technique, the researchers achieved a world-first by visualizing the entire three-dimensional vascular network of the renal artery, vein, and interlobular arteries and veins in the renal cortex, each measuring 167 micrometers in thickness—all without the need for a contrast agent.
The team also conducted continuous observations of renal vascular changes in an animal model induced with renal failure. They performed multivariate analysis using hemodynamic and vascular morphological indicators, revealing a sharp decrease in renal blood flow during acute renal failure. In the case of diabetic nephropathy, chronic vascular degeneration in the kidneys accompanied by vascular distortion was identified.
Professor Chulhong Kim, explaining the significance of the system, stated, “The system allows us to understand the pathophysiology of diseases leading to kidney failure, enabling the observation of vascular changes before and after kidney transplantation.” The technology also holds considerable potential for studying blood circulation and functional impairment across various organs, including the digestive system, circulatory system, and cerebral nervous system.
In summary, the POSTECH research team’s ultrafast ultrasound technique represents a groundbreaking advancement in imaging the intricate microvasculature of the kidneys. This non-invasive approach without the need for contrast agents opens new possibilities for understanding, diagnosing, and monitoring kidney-related conditions, with broader applications in studying vascular changes across different organs.
Journal Reference
Donghyeon Oh et al, Contrast Agent‐Free 3D Renal Ultrafast Doppler Imaging Reveals Vascular Dysfunction in Acute and Diabetic Kidney Diseases, Advanced Science (2023). DOI: 10.1002/advs.202303966.
