Endoscopic Injections of Botulinum Toxin Type A in the Piglet Esophagus Is Safe and Feasible but Did Not Result in any Significant Structural Changes 3 Days after Injection

Endoscopic Injections of Botulinum Toxin Type A in the Piglet Esophagus Is Safe and Feasible but Did Not Result in any Significant Structural Changes 3 Days after Injection

Response to: Endoscopic Injections of Botulinum Toxin Type A in the Piglet Esophagus Is Safe and Feasible but Did Not Result in any Significant Structural Changes 3 Days after Injection

I read with interest the article entitled: “Endoscopic Injections of Botulinum Toxin Type A in the Piglet Esophagus Is Safe and Feasible but Did Not Result in any Significant Structural Changes 3 Days after Injection” by Rose M, Clarke P, Pike AH, Zvara P, Schrøder HD, Hejboel EK, Qvist N, and Ellebæk MB,[1] which was published in the June, 2022, issue of the European Journal of Pediatric Surgery. The article was very well developed for which I must congratulate you; however, I cannot let it pass that it was on the third day after intramural injection with botulinum toxin type-A (BTX-A) that the esophagus was harvested and tested in a stretch-tension machine to evaluate elongation and maximum load, followed by histological examination. As reported in the international literature, the toxin has a reversible paralytic effect that usually peaks about 1 to 2 weeks after injection. Therefore, it is suggested to wait for 1 to 2 weeks to manipulate the tissue post injection because of this theoretical peak in efficacy.[2]

Your aim was clear: to determine if endoscopic injections would be feasible, safe, and have an effect on the mechanical properties of the esophagus. However, testing the elongation of the esophagus on the third day after placing the BTX-A would not be appropriate if we are looking for a good result, because although, as explained in the literature, the action of the BTX-A can begin after 24 hours, its greatest effect occurs 1 or 2 weeks after the injection.[2] [3] Even in the randomized controlled blinded animal trial, published by Svensson et al[4] they specify it in materials and methods that after 14 days stricture formation, presence of leakage, and esophageal compliance are assessed using endoscopic and manometric techniques and in vivo and ex vivo contrast radiography.

It would be advisable for future studies in which the BTX-A is used to wait for the optimal times of greatest effect (1 to 2 weeks) for a more aim evaluation.

Publication History

Received: 14 December 2022

Accepted: 16 February 2023

Accepted Manuscript online:
21 February 2023

Article published online:
05 April 2023

• References

• 1 Rose M, Clarke P, Pike AH. et al. Endoscopic injections of botulinum toxin type A in the piglet esophagus is safe and feasible but did not result in any significant structural changes 3 days after injection. Eur J Pediatr Surg 2022; 32 (05) 460-464
• 2 Fu KJ, Teichgraeber JF, Greives MR. Botulinum toxin use in pediatric plastic surgery. Ann Plast Surg 2016; 77 (05) 577-582
• 3 Capece SJ, Wallace SJ, Wojcik R, Browne M. Botulinum toxin for giant omphalocele abdominal wall reconstruction. J Pediatr Surg Case Rep 2020; 61: 101562
• 4 Svensson E, Zvara P, Qvist N. et al. The effect of botulinum toxin type A injections on stricture formation, leakage rates, esophageal elongation, and anastomotic healing following primary anastomosis in a long- and short-gap esophageal atresia model—a protocol for a randomized, controlled, blinded trial in pigs. Int J Surg Protoc 2021; 25 (01) 171-177