Lymphoscintigraphy versus Indocyanine Green Lymphography—Which Should Be the Gold Standard for Lymphedema Imaging?

Abstract

Early detection and treatment can slow the progression of lymphedema. To diagnose lymphedema in the subclinical phase, a sensitive imaging modality is required. Radioisotope-based lymphoscintigraphy (LSG) has been the “gold standard” for a century. Indocyanine green lymphography (ICGL) is being used at our institute for diagnosing and grading all lymphedema patients. In this study, ICGL disease detection rate was compared to that of LSG. Chart review of all patients who presented for lymphedema consult between February 2020 and April 2022 was conducted. Patients who underwent both LSG and ICG for extremity edema in symptomatic/asymptomatic limbs were included. A total of 50 limbs in 23 patients met the inclusion criteria. Of those, 37 were symptomatic and 13 were asymptomatic. LSG detected lymphatic dysfunction in 26/37(70%) of the symptomatic limbs while ICG detected the same in 37/37(100%) limbs (p < 0.01). In the asymptomatic group, LSG detected the disease in 1/13(8%) limbs while ICG detected lymphatic dysfunction in 8/13 (62%) limbs (p < 0.01). LSG missed symptomatic limbs 30% of the time, whereas ICG did not miss any symptomatic limbs (p < 0.01). LSG missed asymptomatic disease 54% of the time (p < 0.01) compared to ICG. In conclusion, ICG lymphography was determined to have a higher lymphatic dysfunction detection rate compared to LSG.