The effects of cross-linked hyaluronate hydrogel and liquid sodium hyaluronate on post-surgical adhesion reformation were examined using a rabbit model. Primary adhesions in the ileocaecal region of Japanese white rabbits were induced by mechanical and chemical irritants during laparotomy. After 1 month the primary adhesions were lysed by microsurgery and cross-linked hyaluronate hydrogel or liquid sodium hyaluronate was applied to the lysed lesions. After 10-14 days the area of adhesion reformation was measured to assess any inhibitory effect of the test materials. Rabbits treated with cross-linked hyaluronate hydrogel showed a significant reduction in adhesion reformation area compared with liquid sodium hyaluronate or physiological saline treatment, and the area reduced to (mean +/- standard deviation) 0.6 +/- 1.95% of the original lesion. In a separate study, histological evaluation of rabbits treated with cross-linked hyaluronate hydrogel revealed a better healing pattern and a lower inflammatory response compared with controls. All these findings suggest cross-linked hyaluronate hydrogel may be a valuable anti-adhesion material to prevent post-surgical adhesion in abdominal or pelvic surgery.