Department of Plastic and Cosmetic Surgery, The First Affiliated Hospital of Hunan Normal University, 61 Jiefangxi Road, Changsha 410005, Hunan Province, PR China.
J Plast Reconstr Aesthet Surg. 2010 Dec;63(12):2026-31. doi: 10.1016/j.bjps.2009.12.019. Epub 2010 Jan 29.
Few reports exist on effective methods of evaluating the effects and selecting indications for the treatment of improving facial morphology by masseteric injection of botulinum toxin type A. The method for selecting indicative factors, as determined by the change of masseteric area volume at a standard frontal view when tightly clenching teeth, was used in this study. Patients with varying masseteric area volume were randomly enrolled. Bilateral masseteric muscles were treated with multi-point percutaneous intramuscular injections of botulinum toxin type A, 30-50 u for each side. Changes in facial appearance and satisfaction of patients were observed and standard frontal view photographs were taken pre-treatment and 2-3 months post-treatment. Following this, the anterior facial height(FH), bizygomatic facial width (FWz) and intergonial width (FWg) were measured from the photographs. The indices of FH/FWz and FWg/FWz were calculated and analysed. The results showed that the volume of masseteric area was reduced and the facial morphology was improved at 2-4 weeks post-injection, with maximum reduction at 2-3 months post-injection. All of the 32 patients were satisfied with the clinical effects. The pre-treatment and post-treatment values of FH/FWz were 0.8309±0.0423 and 0.8331±0.0382, respectively, and FWg/FWz values were 0.8281±0.0209 and 0.7925±0.0206 (P<0.01), respectively. In conclusion, the appropriateness of masseteric injection of botulinum toxin type A for improving facial morphology can be determined by the changes in masseteric area volume at a standard frontal view of tightly clenched teeth. In addition, the facial index of FWg/FWz can be used to evaluate the treatment.
关于评估肉毒毒素 A 注射治疗改善面型效果及选择适应证的有效方法，目前仅有少数报道。本研究采用咬牙紧咬时标准正位视图下咬肌区域体积变化来选择指示因素的方法。选择不同咬肌区域体积的患者进行随机分组。双侧咬肌均采用多点经皮肌内注射肉毒毒素 A，每侧 30-50u。观察患者面部外观变化和满意度，并在治疗前和治疗后 2-3 个月拍摄标准正位照片。然后，从照片中测量前面部高度(FH)、面宽(FWz)和颏下宽(FWg)。计算并分析 FH/FWz 和 FWg/FWz 指数。结果显示，注射后 2-4 周咬肌区域体积减少，面型改善，2-3 个月时达到最大效果。32 例患者均对临床效果满意。治疗前后 FH/FWz 值分别为 0.8309±0.0423 和 0.8331±0.0382，FWg/FWz 值分别为 0.8281±0.0209 和 0.7925±0.0206（P<0.01）。结论：通过咬牙紧咬时标准正位视图下咬肌区域体积的变化，可以确定肉毒毒素 A 注射治疗改善面型的适宜性。此外，FWg/FWz 面部指数可用于评估治疗效果。
