Intraoperative Botulinum Toxin and Sialocele Incidence After Parotidectomy

Postoperative sialocele is a complication of parotidectomy and, in some cases, may require multiple follow-ups or necessitate needle aspiration. The purpose of this study was to assess whether intraoperative botulinum toxin A injection is associated with decreased incidence of sialocele formation after parotidectomy.

This retrospective cohort study included patients who underwent parotidectomy by one of five surgeons between January 2020 and February 2026. The association between intraoperative botulinum toxin and postoperative sialocele incidence was evaluated with multivariable logistic regression with CR2 cluster-robust variance estimation. Propensity-score weighting and 30-day outcome-ascertainment sensitivity analyses were also performed.

A total of 295 patients were included. 10.8% (32/295) developed postoperative sialocele. The incidence of sialocele in patients who did not receive intraoperative botulinum toxin was 12.3% (27/220) compared with 6.7% (5/75) in patients who received intraoperative botulinum toxin. In the primary multivariable model, botulinum toxin was associated with a lower estimated odds of sialocele formation, though the 95% CI narrowly included the null (adjusted OR: 0.43; 95% CI: 0.188-1.005; p = 0.050). Propensity-score overlap weighting demonstrated similar results (OR: 0.43; 95% CI: 0.14-1.38; p = 0.155). In a sensitivity analysis restricted to patients with ascertainable 30-day outcomes, the adjusted OR was 0.27 (95% CI: 0.07-1.00; p = 0.049).

This retrospective cohort analysis suggests that intraoperative botulinum toxin may decrease the odds of postoperative sialocele formation. Botulinum toxin may represent a useful preventative adjunct in an appropriately selected patient, but a prospective study is needed to better define its efficacy, optimal indications, and cost-effectiveness.