Published online Mar 14, 2017. doi: 10.3748/wjg.v23.i10.1828
Peer-review started: October 27, 2016
First decision: December 28, 2016
Revised: January 6, 2017
Accepted: January 18, 2017
Article in press: January 18, 2017
Published online: March 14, 2017
Processing time: 138 Days and 6.3 Hours
To establish and evaluate an experimental porcine model of fistula-in-ano.
Twelve healthy pigs were randomly divided into two groups. Under general anesthesia, the experimental group underwent rubber band ligation surgery, and the control group underwent an artificial damage technique. Clinical magnetic resonance imaging (MRI) and histopathological evaluation were performed on the 38th d and 48th d after surgery in both groups, respectively.
There were no significant differences between the experimental group and the control group in general characteristics such as body weight, gender, and the number of fistula (P > 0.05). In the experimental group, 15 fistulas were confirmed clinically, 13 complex fistulas were confirmed by MRI, and 11 complex fistulas were confirmed by histopathology. The success rate in the porcine complex fistula model establishment was 83.33%. Among the 18 fistulas in the control group, 5 fistulas were confirmed clinically, 4 complex fistulas were confirmed by MRI, and 3 fistulas were confirmed by histopathology. The success rate in the porcine fistula model establishment was 27.78%. Thus, the success rate of the rubber band ligation group was significantly higher than the control group (P < 0.05).
Rubber band ligation is a stable and reliable method to establish complex fistula-in-ano models. Large animal models of complex anal fistulas can be used for the diagnosis and treatment of anal fistulas.
Core tip: Different new surgical methods for fistula-in-ano such as fibrin sealant or AFP plug should be used to establish animal models before a clinical trial begins. We established an experimental porcine anal fistula model using a rubber band ligation method which may provide a possible platform for anorectal fistula research. This surgical method using rubber band ligation is more stable and reliable than an artificial damage technique. Our porcine model of fistula-in-ano was confirmed by histopathology and anatomically similar to humans. This porcine model of fistula-in-ano can be used in the diagnosis and treatment of anal fistulas.