Purpose The objective of this study was to evaluate the heparin effect for a viability of random-pattern dorsal flap in hairless mouse.
Methods. A caudally-based random dorsal flap, measuring 1.5x5cm, was designed and heparin was applied topically after microneeding. Twenty five male hairless mice were randomly divided into control (Group1, n=5); received only microneedling to (Group 2, n=5), heparin(Group3, n=5), microneedling with saline(Group 4, n=5), and microneedling with heparin group(group5,n=5) to the flap during 7 days. The number of the capillaries were compared between the experimental group and control group with respect to neovascularization after heparin application using imaging analysis program under hematoxylin-eosin stain. The capillary blood flow was measured by laser Doppler flowmetry. After seven days each animal was evaluated for the percentage area of the flap survival. Mann-Whitnety U test and Kruskal-Wallis statistical analysis of survival relationships was performed.
Results  It can be observed increased number of the blood vessels in the experimental groups however it was not statistically significant. Blood flow of the haparin with microneedling group maintained higher than other experimental groups. Treated microneeding and heparin mice were significantly better flap viability than in controls (flap survival  67 % and  54.4mm² respectively; p<.01). Positive correlation was shown between flap survival rate and laser Doppler flux value only at first day after surgery.
Conclusion Heparin has a beneficial effect on capillary flow and improve peripheral circulatory disturbances in random pattern flaps.
Key words: Heparin, Topical application, Microneedle