Modern Day Role for Lymphoscintigraphy in Management of Lymphoedema?

Abstract

Introduction: Lymphoscinigraphy is recognised as the investigation of choice to confirm the diagnosis of Lymphedema. However there is no universal agreement on protocol of the test and timing of uptake measurements. The scan uptake often does not correlate with clinical severity1. This questions the utility of this specialised and costly test. Methods: All patients who were referred to a single consultant with a persumed diagnosis of Lymphoedema were included in the study in 2017. All patients underwent a venous scan and if the venous scan was normal, underwent a Lymphosciniti scan. Clinical findings were compared with scan findings. Results: The scan protocol involved subcutaneous injection of the nanocolloid tracer (Nanocol) in 1st web space in each foot. and quantifying the uptake at the groin immediately and at 2 hours after the injection. Uptake less than 8% at 2 hours was considered abnormal, as was dermal backflow. Normal range being 9-14%. A total of 39 scans were done in the study period. 13 scans showed significant bilateral decrease in uptake at 2 hours, but only 6 patients had bilateral symptoms. Often the less swollen leg and lower uptake compared to the grossly swollen leg. In 10 scans unilateral impairment was noted but the percentage uptake did not correlate with clinical severity. In 3 scans uptakes of 19-22% were recorded suggesting venous oedema. in 11 cases patients the scans were normal, these patients also had normal venous scans. Thereby labelling the swelling as Lipedema. Conclusion: There seems to be an overdependence on Lymphoscintigraphy in diagnosis of Lymphoedema. In this small study there was no correlation between the percentage uptake and clinical severity. It may be more useful to use it to exclude the diagnosis of Lymphoedema and label the swelling as lipedema.