Revolutionary MRI Method Visualizes Lymphatic Vessels with Unprecedented Clarity

A groundbreaking new MRI technique developed by Korean researchers offers a revolutionary way to visualize the entire lymphatic system by injecting contrast dye into an arm vein, eliminating the need for invasive groin injections. This innovative method has successfully provided clear images of lymphatic vessels in the liver and mesentery, areas previously difficult to examine with conventional methods. The technique was developed and its efficacy validated by a research team comprising Professor Beomseok Heo from Radiology at Seoul National University Hospital, Professor Sung-Hwan Yoon from the Biomedical Research Institute, and Professor Ryeo-Min Kwon from Radiology at Hallym University Medical Center.

The Importance and Challenges of the Lymphatic System

The body's lymphatic system plays a crucial role in immunity and maintaining fluid balance. However, damage to these vessels, often resulting from cancer surgery, can lead to lymph leakage. This leakage can cause malnutrition and a weakened immune system. Statistics show that approximately 6 to 7 out of every 100 patients experience lymph leakage after colorectal cancer surgery. Unfortunately, existing standard diagnostic methods have struggled to pinpoint the exact location of this leakage.

Limitations of Existing Diagnostic Methods

Traditional methods like lymphaticography based on injection into inguinal lymph nodes and Dynamic Contrast-Enhanced MR Lymphangiography (DCMRL) were technically challenging, requiring precise needle placement into the inguinal lymph nodes. Consequently, visualizing the liver and mesenteric lymphatic vessels, which account for over 70% of lymph production, was nearly impossible. Research indicates that for patients with mesenteric lymphatic vessel damage, the success rate of identifying the leakage site was only about 55%, highlighting the significant difficulties involved.

Principle and Efficacy of the New MRI Technique

The research team initially conducted studies on pigs, injecting contrast dye intravenously and comparing concentration changes in blood and lymph fluid. They observed a phenomenon called lymphatic enhancement, where contrast agent concentration in the lymph fluid became higher than in the blood approximately 20 to 30 minutes after injection. MRI scans clearly depicted the lymphatic vessels, showing a signal intensity in the chyliferous vessels about 5.5 times higher than in the surrounding muscles.

A pilot clinical study involving 16 patients suspected of having lymph leakage was conducted from September 2024 to August 2025. This study also demonstrated a significant increase in signal ratio after injection, opening up the possibility of visualizing the liver and mesenteric lymphatic vessels, which were previously inaccessible with the conventional groin injection method.

Anticipating Enhanced Diagnostic Accuracy in the Future

Professor Heo stated, "Unlike traditional lymph node injections, the intravenous injection method, IV-MRL, can be performed solely through a vascular injection, reducing procedural difficulty and patient discomfort." He added, "We anticipate this will enhance diagnostic accuracy for lymphatic leakage diseases and contribute to the development of effective treatment strategies in the future."

With the development of this new technique, a pathway has been opened to identify lymph leakage sites within the body, whether in the groin or the liver, without the need for invasive needle procedures. This offers significant hope for patients.