[Management of primary non-classifiable anal fistulas].

UNLABELLED: In the surgery of anal fistulae, very demanding problems warranting special consideration are caused by the non-classifiable fistulae in ano.

RESULTS

Of 823 patients who underwent surgery for anal fistulae between 1993 and 1996, 38 (4.5%) were, according to Parks' classification, non-classifiable; the anal canal was intact. There was no internal opening. All patients had already undergone operations, some of them multiple. In 53%, complete healing of the fistula was achieved by using a single excision. In 47% a recurrence developed. During a second revision we explored the intersphincteric space and were able to reclassify the fistulae in 50% of the cases. A continent fistulectomy led to complete healing in these patients.

CONCLUSION

Non-classifiable fistulae in ano, in which an internal opening of the fistula cannot be found, can primarily be treated by a single excision of the fistula. If recurrence does occur, the patient should undergo exploration of the intersphincteric space in the region, where the cryptoglandular infection is suspected.