Abstract
To the Editor:
We thank Garg and his team for their interest in our article 1 and positive comments. We have read the letter titled “LTE re Li TROPIS” by Garg focusing on the fundamental principle and effects of the transanal opening of intersphincteric space (TROPIS) procedure. The TROPIS procedure seems to be an effective sphincter-saving procedure for highly complex fistulas, including fistulas associated with acute abscess.1-3 As mentioned by Garg, the transanal laying open of the intersphincteric space of the fistula tract was mainly performed for intersphincteric abscess and “pure” intersphincteric fistulas until recently. We consider the main reason to be the lack of insight about the principle of the TROPIS procedure. This procedure includes opening the intersphincteric space into the rectum and managing the external tract effectively. On one hand, the portion of fistula within the external sphincter is laid open via the transanal route. On the other hand, the residual fistula is managed by different methods, for example, excision, electrocautery, and curettage and laser excision.
The anatomical structure of the area inevitably results in the inclusion of the sphincter during anal fistula surgery. The TROPIS procedure involves laying open the intersphincteric space by cutting off the internal anal sphincter transanally, whereas the external sphincter is not cut or damaged; hence, there is no effect on continence. Therefore, we re-emphasize that although sphincter-saving procedure involves sphincter injury, it preserves anal function as much as possible with an acceptable cure rate.
We highly appreciate Garg’s opinion that the TROPIS procedure is a promising sphincter-saving procedure with satisfactory cure rate for highly complex fistulas. We look forward to more prospective, randomized controlled trials to verify the effectiveness of this procedure.