Ultrasound-Assisted Lymphaticovenular Anastomosis for the Treatment of Peripheral Lymphedema
This procedure is performed using a linear skin incision of 2 to 3 cm in length through which the lymphaticovenular anastomosis is performed. So far, preoperative skin incision planning is crucial. The skin incision should be placed in an area where the target lymphatic collector to be bypassed can be found and a favorable nearby venule can be located.
Although lymphatic collector mapping can be performed by indocyanine green lymphography, this is true in cases with less severe lymphedema, where the dermal backflow does not obscure the underlying collectors. Moreover, an increased panniculus width because of high body mass index, anatomical area feature (i.e., thigh and arm), or lymphedema soft-tissue changes may interfere with indocyanine green navigation potential.
Venule detection has been a topic usually not much highlighted in the literature. Noncontact vein visualization infrared devices have been reported as tools for mapping cutaneous venules and to plan surgical access. However, those tools have two main limitations: depth-dependent visualization and the lack of functional visualization (i.e., blood backflow).3,4 According to our experience, the ideal recipient vein for lymphaticovenous anastomosis should have two main features: good caliber matching with lymphatic collector, and absence of blood backflow.
From this perspective, color Doppler ultrasound became our standard in preoperative planning of lymphaticovenular anastomosis. Color Doppler ultrasound allows visualizing both lymphatic collectors and venules.
As for collectors, this is useful in two circumstances: (1) when a lymphatic channel has been detected with indocyanine green lymphography, because its caliber can be determined; and (2) when indocyanine green lymphography cannot detect any collector, color Doppler ultrasound will aid in its visualization.5 As for the venule, color Doppler ultrasound is superior to other tools, as it allows precise location of the venule, to determine its caliber for better matching with the collector and, moreover, to preoperatively assess the absence of blood reflux within the selected venule for the presence of a valve. When superficial venous insufficiency is found, perforators can be mapped to perform a lymphatico comitantes venule perforator anastomosis.5 In our experience, preoperative color Doppler ultrasound is a very useful tool with which the lymphaticovenular anastomosis surgeon can plan skin incisions more efficiently and also allows reduction of operative exploration time.