The dosage and timing of BTA therap

The dosage and timing of BTA therapy varied between studies. Ten studies adopted single injection, among them, nine studies were postoperative or intraoperative injection, onestudy was preoperative single injection, and one study used a two-stage injection. Although there was no standardization of the treatment algorithm, several mutual characteristics can besummarized from the included studies and the pooled result. First, the results suggest that BTA can contribute to improving the quality of surgical scars in face or neck for Asians or patients with Fitzpatrick’s skin type III-V. This qualification regarding skin type is necessary, because the majority of the analyzed studies included only Asians or patients with higher levels of Fitzpatrick’s skin type; only two studies38,45 consisted entirely of Caucasian patients, and these exhibited controversial results: one detected favorable results in the BTA treated group, while the other noted improvement only in patients with severe scar histories. Thus, there is inadequate evidence presented in this paper to support the use of BTA in Caucasians for primary surgical scars in face and neck, but if the patient has a medical history of hypertrophic scars or keloids, prophylactic BTA injection may be helpful.