Pathological analysis of opened round ligaments as venous patch grafts in living donor liver transplantation

Abstract

Although the round ligament, including the umbilical vein, could be used as a venous graft in living donor liver transplantation (LDLT), no studies have determined its appropriate use on the basis of pathological findings. We prospectively examined 19 LDLT cases in which the donor's round ligament was procured and used as a venous graft. The round ligaments were categorized into 3 types based on the CD31 immunohistochemistry of tissue cross-sections: (I) canalized umbilical veins (n 5 7 or 36.8%), (II) capillary umbilical vessels (n 5 4 or 21.1%), and (III) occluded umbilical veins (n 5 8 or 42.1%). After dilatation and incision, the round ligaments provided patch grafts that were 5.8 6 0.4 cm long and 1.8 6 1.2 cm wide. However, histological studies showed the absence of fine intimal layers on the dilated round ligaments after mechanical maneuvers. The ligaments were used to cuff the venous orifices in 15 patients (left lobe, n 5 8; right lobe, n 5 7) and were used as venous bridges in 4 patients (left lobe, n 5 2; right lobe, n 5 2). We detected no thrombosis at the implant sites after LDLT. Our pathological findings indicate that opened round ligaments can be used safely as venous patch grafts in LDLT.

Feasibility of All‐in‐One Venoplasty With a Venous Cuff Using an Opened Round Ligament for the Right Lobe Graft in Living Donor Liver Transplantation

“…Therefore, we prefer to use the recipient’s round ligament as the bridge for joining the RHV, MHV tributaries, and IRHV, instead of the IJV or EPV, besides, the donor’s round ligament was applied to create for the venous cuff. In addition, the cross‐sectional images of the round ligaments from donors by CD31 immunohistochemistry revealed that only approximately one‐third of the round ligaments in adults contained an open umbilical vein as the type of canalized umbilical vein . However, there seem to be no significant differences between the patients with opened umbilical veins and the patients with unopened umbilical veins in clinical use as patch grafts, and no thrombosis and stenosis were detected at the implant site of the opened round ligament as the venous patch .…”

“…In addition, the cross‐sectional images of the round ligaments from donors by CD31 immunohistochemistry revealed that only approximately one‐third of the round ligaments in adults contained an open umbilical vein as the type of canalized umbilical vein . However, there seem to be no significant differences between the patients with opened umbilical veins and the patients with unopened umbilical veins in clinical use as patch grafts, and no thrombosis and stenosis were detected at the implant site of the opened round ligament as the venous patch . Nevertheless, further pathological and clinical studies are necessary for evaluating the feasibility of using the opened round ligaments of the donors as the venous cuff compared with the various other grafts such as EPV, inferior mesenteric vein, and IVC, and so on.…”

“…Various hepatic vein reconstruction techniques such as autologous inferior vena cava (IVC) patch grafts, internal jugular vein (IJV), saphenous vein, explanted portal vein (EPV), homologous cryopreserved vein grafts, and prosthetic vascular grafts have been reported to overcome primary graft dysfunction or small‐for‐size graft syndrome in living donor liver transplantation (LDLT) using a right lobe (RL) graft without the middle hepatic vein (MHV) trunk . However, large‐sized vein allografts are often limited, and their postoperative patency after surgery has not been evaluated.…”

Recanalized umbilico‐caval anastomosis as a temporary portosystemic shunt in pediatric living donor liver transplantation: the crossed fingers method

“…Transumbilical portal venous catheterization to reopen the round ligament and insert the catheter during adult left lobe LDLT has been reported to be a useful method for measuring the portal venous pressure and perfusing the graft . Recanalized umbilical veins have been used successfully as interposition grafts to drain major middle hepatic vein tributaries during right lobe LDLT; this vein graft offers a large caliber, thick wall, and well‐preserved intima . Using the opened round ligament as a long conduit for in‐ and outflow venous reconstruction has still been controversial because of the higher incidence of thrombosis, but it might be safely used as a TPCS.…”

“…This structure represents the remnant of the fetal umbilical vein and is patent prenatally and for 1‐2 months after birth . However, the round ligament can be recanalized after mechanical dilatation, because the majority of the umbilical veins have an endothelial lining . Therefore, a sufficient length of left portal vein can easily be connected with vena cava if we perform the intrahepatic dissection of the left portal vein freely up to the remnant of the umbilical vein and use a patent or re‐canalized umbilical vein …”