Effects of a Monophasic Cross-Linked Hyaluronic-Acid Gel in Prevention against Postoperative Adhesion Formation in Rats

This study was conducted to evaluate the anti-adhesion effect by applying monophasic cross-linked hyaluronic acid after induction of intraperitoneal adhesions in rats. A total of 18 rats were divided into the control group, the hyaluronic acid (HA) group treated intraperitoneally with HA gel, and the monophasic cross-linked hyaluronic acid (MCHA) group treated with a MCHA gel intraperitoneally. To evaluate the degree of intra-abdominal adhesion, the thickness of the adhesion site, the degree of inflammatory cell infiltration, the degree of collagen fiber formation, and the adhesion formation score were evaluated. The thickness of adhesion site between the abdominal wall and intestinal mucosa was 1,591.25 ± 263.10 μm in the control group, 989.12 ± 163.46 μm in the HA group, and 716.83 ± 94.01 μm in the MCHA group. The number of inflammatory cells was 341.67 ± 115.69 cells/mm², 175.00 ± 29.14 cells/mm² and 99.67 ± 17.22 cells/mm² in the control, HA, and MCHA group, respectively. The degree of collagen fiber formation at the adhesion site was 71.77 ± 10.26%/mm², 50.12 ± 5.41%/mm² and 42.83 ± 7.30 %/mm² in the control, HA, and MCHA group, respectively. The histopathological grades of adhesion sites were 2.90 ± 0.32, 2.30 ± 0.48, and 1.00 ± 0.47 in the control, HA, and MCHA group, respectively. The results showed the anti-adhesive effect through the anti-inflammatory and anti-fibrotic activity according to the intra-peritoneal treatment of monophasic cross-linked hyaluronic acid gel. Therefore, intraperitoneal treatment of monophasic cross-linked hyaluronic acid gel can be used as an effective anti-adhesion agent in abdominal surgery.