Inguinal intranodal CT lymphangiography for thoracic duct injury: feasibility with rapid scanning

To demonstrate the optimized protocol for CT lymphangiography (CTL) and describe its performance in pediatric and adult patients with suspected thoracic duct injury.

Patients with suspected thoracic duct injury who underwent either CTL or dynamic contrast-enhanced MR lymphangiography (DCMRL) between August 2017 and July 2024 at a tertiary referral center were retrospectively evaluated. CTL and DCMRL were performed using inguinal lymph node cannulation. Total scan time, the number of enhanced scans, technical success, results of lymphatic interventions, and clinical outcomes were recorded. Radiation dose was recorded for CTL. The acquisition results of CTL were described with reference to the results from a previously performed cohort of DCMRL.

A total of 57 CTL (mean age, 48.3 ± 26.4 years; 13 pediatric patients) and 44 DCMRL (mean age, 60.2 ± 16.3 years; 2 pediatric patients) procedures were included. Technical success was achieved in 96.5% (55/57) of CTL and 93.2% (41/44) of DCMRL procedures. Median of total procedure time was 17 min for CTL (median of 4 enhanced scans) while 36 min for DCMRL (median of 8 enhanced scans). The CTL findings for thoracic duct injury types were 42 partial disruptions (76.4%), 10 total disruptions (18.2%), and 3 sealed-off status (5.5%). The mean effective dose of CTL was 7.7 mSv (9.0 mSv for adults, 3.3 mSv for pediatric patients). Improvement in chylous leakage was observed in 100.0% of CTL and 95.5% of DCMRL patients.

CTL successfully depicted central lymphatics and thoracic duct injury with short examination times and an acceptable radiation dose.

Question The utility of contrast-enhanced CT lymphangiography (CTL) has only been explored in animal studies and small case series. Findings Performed in patients with thoracic duct injury, CTL successfully depicted central lymphatics (median scan time, 17 min; mean effective dose, 7.7 mSv). Clinical relevance CTL can be a valuable option for lymphangiography, particularly when rapid imaging or better accessibility is needed.