Illustration of the vascularized lymph node transplantation models. (a) Vascularized cervical lymph node transplantation model. (b) Vascularized mesenteric lymph node transplantation model. (c) Vascularized inguinal lymph node transplantation model (Reprinted with permission, Cleveland Clinic Center for Medical Art & Photography ©2013. All Rights Reserved)
Vascularized Cervical Lymph Node Transplantation Model (Fig. 49.1a)
The rat is placed in the supine position. Skin incision starts at the midline at superior border of sternum and extends transversely to the both sites of neck area. Next, the incision extends to the anteroposterior and cranial directions. Meticulous dissection of the neck skin from the underlying lymphatico-adipose tissue starts from the transverse incision line and extends cranially. The submandibular gland is excised. The external jugular vein with its anterior and posterior facial branches is identified. The posterior facial vein is ligated and transected. The anterior facial vein and its lymph node branches are preserved. The sternocleidomastoid muscle is detached from its sternoclavicular and mastoid insertions and is excised to expose the common carotid artery and its main branches, the external and internal carotid arteries. The posterior belly of the digastric muscle is excised, the omohyoid muscle is transected and the greater horn of the hyoid bone is excised for better visualization of the external carotid artery and its branches. Next, the internal carotid artery, superior thyroid artery, ascending pharyngeal artery, ascending palatine artery, superficial temporal artery, posterior auricular artery, lingual artery and internal maxillary artery and the branches of facial artery (except glandular branches) are ligated and transected. The glandular branches of the facial artery are preserved and are included into the flap. Finally, the common carotid artery and external jugular vein were used as the vascular pedicles of the lymph node flap. The length of the vascular pedicle is in a range between 2.5 and 3.0 cm. One single flap includes five to six lymph nodes. This flap contains higher number of lymph nodes than vascularized inguinal lymph node model. It is versatile, suitable for peripheral vascular anastomoses and relatively easy to dissect.
Vascularized Mesenteric Lymph Node Transplantation Model (Fig. 49.1b)
The rat is placed in the supine position. The abdomen is opened by a midline incision and the aorta is isolated from beneath the celiac artery to below the superior mesenteric artery and all its branches, except the superior mesenteric artery, are ligated and divided. The portal vein is divided below the level of the duodenal-jejunal junction. All jejunal branches from the superior mesenteric arteries and veins are ligated and divided. All these branches were ligated and cut immediately under the intestinal wall for lymph nodes preservation. The aorta is divided to produce an aortic segment with attached superior mesenteric artery supplying the flap. The portal vein is divided at the liver hilum and all lymph nodes and lower part of pancreas with aortic segment and portal vein are excised. This flap contains highest amount of lymph nodes but it is not suitable for peripheral vascular anastomoses and dissection of the flap is hard.