Abstract No. 589 Utility of dynamic contrast magnetic resonance lymphangiography in the diagnosis and treatment of plastic bronchitis

Abstract

Recently, intranodal lymphangiography (IL) and thoracic duct embolization (TDE) have been described as a treatment of plastic bronchitis. Additionally, dynamic contrast MR lymphangiography (DCMRL) has been used to detail the central lymphatic anatomy prior to TDE. The purpose of the present study is to examine the utility of preintervention DCMRL for treating patients with clinically diagnosed plastic bronchitis (PB). Review of IR QA database (Hi-IQ) was performed to identify patients referred for TDE. Between 2016-19, 46 patients (21F:25M, mean age 51 years) were referred to interventional radiology for treatment of clinically diagnosed PB. Medical records were reviewed for imaging (DCMRL and IL) findings and outcome of TDE. Of the 46 patients referred for PB, 37 underwent DCMRL prior to IL and TDE. Reasons pts did not undergo DCMRL included obesity (n = 7), pacemaker dependent (n = 1), and critically ill (n = 1). In 32/37 patients (86%), DCMRL demonstrated abnormal lymphatic perfusion of central bronchi or lungs arising from the TD indicating a lymphatic etiology of PB. In the remaining 5 subjects, lymphatic anatomy was normal. All 37 patients subsequently underwent IL and TD cannulation for TDE. IL/TDE confirmed aberrant lymphatic perfusion in 32/32 (100%) of patients with DCMRL findings diagnostic for lymphatic etiology of PB. In the 5 patients with normal DCMRL, the IL and cannulation of the TD were also normal. Lymphazurin blue was injected into the TD via a microcatheter while bronchoscopy was performed in these 5 patients, and none were found to have the dye appear in the submucosal lymphatics of the airway, further confirming abnormal pulmonary lymphatic perfusion was not present. The PPV and NPV of DCRML for lymphatic origin of PB was 100% (P <0.001). In the 32/37 patients with positive DCMRL, TDE was performed with coils and N-BCA glue. In 31/32 embolized patients, symptoms resolved completely. In one patient, symptoms resolved but recurred requiring a second TDE. DCRML has a high PPV and NPV for confirming a lymphatic etiology of PB. These findings suggest DCMRL should be performed on all patients with PB to confirm the etiology of PB prior to undergoing TDE.