A prospective and randomized study comparing ultrasound‐guided real time injection to conventional blind injection of botulinum neurotoxin for glabellar wrinkles

Background Botulinum neurotoxin injections are the most frequently performed cosmetic procedures, but conventional blind injection for glabellar wrinkles remains to have some limitations. Aims We intend to directly inject botulinum neurotoxin into the glabella complex guided by real time ultrasound. We aim to propose a more efficient and safer botulinum neurotoxin injection strategy for glabellar wrinkles. Methods A total of 40 subjects with moderate to severe glabellar lines were enrolled in this study to receive botulinum neurotoxin injection, either through ultrasound‐guided real time injection or conventional blind injection. Facial Wrinkle Scale (ranging from 0 = none to 3 = severe) and inter‐brow distance (from 3D scanned face images) were used to evaluate the glabellar wrinkles improvement. Paired t test and two‐sample t test were performed to analyze the within‐group and between‐group differences. Results The wrinkle score reduction was significant (p