# Imaging and evaluation of cervicothoracic lymphatic drainage pathways in single ventricle patients with Fontan circulation using the mDixon steady state MR angiography

## TL;DR

This study shows that a type of MRI can effectively visualize lymphatic pathways in patients with Fontan circulation, helping assess their risk for lymphatic-related complications.

## Contribution

The study demonstrates the utility of 3D mDixon steady state MR angiography for high-resolution imaging of cervicothoracic lymphatic pathways in Fontan patients.

## Key findings

- Image quality was rated as very good or good in over 90% of cases.
- Five out of six patients with lymphatic complications had higher pathway types (type 3 or 4).
- 3D mDixon MR angiography provides high-quality visualization of both cardiovascular and lymphatic anatomy in Fontan patients.

## Abstract

Single ventricle (SV) Fontan patients are at risk for the development of pathological cervicothoracic lymphatic drainage pathways that are involved in the development of serious conditions such as plastic bronchitis or chylothorax. Visualization and categorization of cervicothoracic lymphatic drainage pathways might therefore help to stratify prognosis and to individualize therapy and follow-up for Fontan patients. This study aimed to show that the 3-dimensional (3D) modified Dixon (mDixon) steady state magnetic resonance (MR) angiography, commonly used to image cardiovascular anatomy, can visualize cervicothoracic lymphatic drainage pathways in high resolution in Fontan patients.

3D mDixon steady state MR angiography of 88 pediatric and young adult patients with a Fontan circulation were retrospectively analysed. The pattern of cervicothoracic lymphatic pathways and image quality according to diagnostic value were assessed. Furthermore, ventricular volumes, mass and ejection fraction from cine imaging were measured.

Image quality was assessed as very good or good in > 90% of the cases. Six patients had a lymphatic complication of which five (83.3%) had a higher cervicothoracic lymphatic pathway type (type 3 or 4).

3D mDixon steady state MR angiography is an established method to assess cardiovascular anatomy and function in Fontan patients. The method also allows to visualize and evaluate the cervicothoracic lymphatic anatomy with high image quality. 3D mDixon steady state MR angiography is therefore particularly useful to comprehensively assess Fontan patients, a patient group prone not only to cardiac but also lymphatic failure.

The online version contains supplementary material available at 10.1186/s12880-025-01803-0.