Structure and surgical dissection layers of the bare area of the liver

Abstract

Background: The bare area was reportedly formed by direct adhesion between the liver and diaphragm, meaning that the bare area lacked serosal components. This study aimed to analyze the structure of the bare area by an integrated study of surgical and laparoscopic images and pathological studies and describe surgical procedures focusing on the multilayered structure. Methods: Several surgical specimens of hepatectomy were analyzed histologically to evaluate the macroscopic structure of the bare area. Laparoscopic images and cadaver anatomy of the bare area were also examined. Results: The multilayered structure of the bare area comprised the liver, sub-serosal connective tissue, liver serosa, parietal peritoneum, retroperitoneal connective tissue, epimysium of the diaphragm, and diaphragm, in order from the liver to the diaphragm. The liver serosa and the parietal peritoneum fused with each other. This multilayered structure of the bare area is observed almost constantly. There are two layers in the dissection of the bare area in surgical procedures, an outer layer of the fused peritoneum (near the diaphragm) and an inner layer of the fused peritoneum (near the liver). Laparoscopic images enabled us to recognize the multilayered structure of the bare area. Conclusions: Histopathological findings showed the bare area to be a multilayered structure. In cases where tumors are located underneath the bare area, it could be important to dissect the bare area, with careful attention to its multilayered structure. Surgical dissection of the bare area in the outer layer of the fused peritoneum could allow a sufficient safety margin.

Embryological, anatomical and clinical considerations on pleuroperitoneal communication

“…The bare area ( area nuda hepatis ) of the liver is a triangular area located at the posterosuperior surface of the right lobe of the liver; it lies between the two layers of the coronary ligament (upper and lower) and the right triangular ligament. It is the only area of the liver devoid of visceral peritoneum covering and is separated by thin multilayered connective tissue from the diaphragm [ 13 ]. Thus, the right hemidiaphragm is in closer contact with the liver than the left hemidiaphragm does with the stomach or the spleen, respectively.…”

Histotopographical Features of the Diaphragm in Normal Conditions and with its Metastatic Lesions

“…Различный характер и распространенность опухолевых диссеминатов на диафрагмальной брюшине (инвазия в мышечный слой диафрагмы, сочетанное поражение печени, сухожильного центра, перикарда) будут определять интраоперационную тактику перитонэктомии [5].…”