Lymphangiogenesis is crucial in the homeostasis of interstitial fluids, immunity, and metabolism. Also, its importance in wound healing has been reported in animal models and clinical studies.[1]
[2] However, the current understanding of lymphangiogenesis through incisional scars is still limited. We present indocyanine green (ICG) lymphography images near a 16-year-old Pfannenstiel scar of a 43-year-old female patient. Informed consent was obtained from the patient for publication of this image report and accompanying images.
The patient underwent a total mastectomy and immediate breast reconstruction using a free transverse rectus abdominis myocutaneous flap. ICG was injected intradermally at seven points: three points superior to, three points superolateral to, and one below the inguinal ligament. Drainage of the ICG was captured using Fluobeam near-infrared fluorescence imaging camera (Fluoptics, Cambridge, MA). Lymphatic drainage from injection point 1 traveled in the cephalic direction, while injection points 2 and 3 (above the scar) formed collaterals with injection point 3 (which is not above the scar). Other injection points showed the inguinal area's previously known lymphatic drainage ([Fig. 1]).
Fig. 1 (A) A schematic illustration of the lymphatic drainage of the inguinal area: indocyanine green (ICG) was injected intradermally at 7 points (numbered). The blue line illustrates the drainage. (B) ICG lymphangiogram of the inguinal area during 10 minutes immediately after injection of the ICG.
One hour delayed ICG lymphography after flap elevation showed multiple lymphatic vessels near the superficial fascia. Interestingly, no lymphatic vessel was visible near the Pfannenstiel scar ([Fig. 2], above the line). ICG quantification showed pooling of the ICG in points 1 and 2, as well as collateral drainage in the cephalic direction ([Fig. 3]).
Fig. 2 Indocyanine green (ICG) lymphangiogram of the inguinal area 1 hour after injection. After flap elevation, multiple lymphatics were seen near the superficial fascia. However, no lymphatics were found near the Pfannenstiel scar.
Fig. 3 Indocyanine green (ICG) quantification: Pooling of the ICG was observed in the first and second injection points. Also, only cephalic (but no caudal) collateral drainages were observed.
In animal models, lymphangiogenesis has been evident near the wound edge 3 to 5 days after incision[3] with a temporary increase of new sprouts from existing lymphatic vessels.[2] On the contrary, our images show that human lymphangiogenesis does not occur through incisional scars. Further animal and clinical studies on lymphangiogenesis near incisional scars are needed.
