Unilateral pedal lymphangiography plus computed tomography angiography for location of persistent idiopathic chyle leakage not detectable by ordinary contrast computed tomography

BACKGROUND To identify the value of unilateral pedal lymphangiography (LPG) plus computed tomography angiography (CTA) in accurate depiction of persistent idiopathic chyluria undetectable by ordinary contrast CT. METHODS Eighteen patients 44-63 years of age with persistent idiopathic chyluria who failed conservative management were included. Ordinary CT had not revealed a chyle leak. Cystoscopy, unilateral LPG, and post-LPG CT angiography (CTA) were sequentially performed. Ligation and stripping of the perirenal lymphatics were subsequently performed guided by lymphangiography and CTA. RESULTS LPG and post-LPG CTA detected 17 unilateral and one bilateral chyle leaks in the 18 patients, with clear images of the communication of lymphatic vessels and the renal collecting or vascular system. The success rate was significantly better than cystoscopy (100% vs 50.0%, P = 0.005) or LPG alone (100% vs. 72.2%, P = 0.016). Chyluria resolved after surgery in all patients; no relapses were found. CONCLUSIONS LPG plus post-LPG CTA accurately characterized perirenal lymphangiectasia that was not demonstrated by routine contrast-enhanced CT or not suitable for magnetic resonance imaging. Despite of its invasiveness, this method is a good diagnostic alternative to LPG in patients with persistent chyluria requiring surgery.