The Confluence Point: A New Incision Strategy for Lymphaticovenular Anastomosis in Peripheral Lymphedema

In the past 5 years, many advances have been made in preoperative planning using new imaging technologies. The high case load of lymphaticovenular anastomosis (LVA) performed using ultra-high-frequency ultrasound led to the discovery of a new incision site-the confluence point-where 2 major functional lymphatic channels merge into one, and then become sclerotic soon after.

From October of 2021 to May of 2022, 60 consecutive patients with extremity lymphedema who underwent LVA were prospectively assessed. Preoperative planning included indocyanine green lymphography and ultra-high-frequency ultrasound. LVAs at the confluence points were evaluated in terms of operative time and LVA dynamics after the anastomosis, and compared with the incisions without confluence points.

The confluence point was detected preoperatively in 26 cases (43%). The lymphatics proximal to the confluence point showed similar calibers to the distal ones, with no significant size increase, and underwent a lumen obstruction 0.5 to 1 cm after the confluence point in 22 cases (92%). The mean operative time for LVA at the confluence points was 39 ± 8 minutes in upper limb lymphedema and 42 ± 6 minutes in lower limb lymphedema, significantly lower compared with incisions with 2 anastomoses (57 ± 8 minutes for upper limb lymphedema [ P < 0.0001] and 69 ± 15 minutes for lower limb lymphedema [ P < 0.0001]).

LVA of confluence points derives from the anatomic findings detectable by ultra-high-frequency ultrasound, and proved to be an effective method to minimize the number of LVAs needed while maintaining the maximal lymph flow and the best dynamics through the anastomosis.

Therapeutic, IV.