Lymphoscintigraphy for prediction of effect of lymphaticovenular anastomosis for treatment of secondary lower limb lymphedema

Abstract

Objective: The outcomes of lymphaticovenular anastomosis (LVA), especially for the lower extremities, have varied. To determine the optimal patient selection for LVA, we evaluated the smooth muscle function of lymph vessels using preoperative lymphoscintigraphy images and compared the findings with the LVA outcomes.

Methods: We performed a retrospective study of 81 patients with secondary lower extremity lymphedema who had undergone LVA between 2016 and 2018. To reduce the variability in the surgeon-specific variables that can affect the outcomes of LVA, all the cases from 2016 onward were performed by only two surgeons using standardized protocols for preoperative care, surgical technique, number of anastomoses, postoperative ambulation, and compression. The outcomes were evaluated by comparing the circumferences of the pre- and postoperative limbs. The preoperative lymphoscintigraphy findings were categorized into three types according to the range of the cephalad extent of the tracer as follows: type 1, tracer extending to the thigh or groin region; type 2, tracer extending to the lower leg or knee; and type 3, tracer localized at the ankle. The quantitative outcomes were evaluated by measuring the circumferences of the ankle, mid-calf, knee, and thigh.

Results: The average percentage in the reduction in the ankle, mid-calf, knee, and thigh circumference was 7.9%, 4.7%, 2.9%, and 3.0%, respectively. The average percentage in the reduction in the circumference for types 1 and 3 at the ankle, mid-calf, knee, and thigh was 11.6% and 8.6%, 7.6% and 1.6%, 5.2% and -0.5%, and 5.4% and -1.2%, respectively, with significant differences between types 1 and 3 in the thigh. The percentage of types 1, 2 and 3 was 60% to 76.4%, 11.7% to 20%, and 0% to 5.5% of the treated limbs that were similar in size to the contralateral healthy limb at the four sites of measurement, respectively.

Conclusions: The use of LVA can effectively reduce the circumference of the lower limb. Our results suggest that the lymphoscintigraphy findings could help to predict the effect of LVA and could facilitate optimal patient selection.

Keywords: Lymphedema; Lymphedema of the lower extremities; Microsurgery; Surgical procedures; Treatment outcome.