AbstractThe evaluation of neuromodulator treatment outcomes can be performed by noninvasive surface-derived facial electromyography (fEMG) which can detect cumulative muscle fiber activity deep to the skin. The objective of the present study is to identify the most reliable facial locations where the motor unit action potentials (MUAPs) of various facial muscles can be quantified during fEMG measurements. The study population consisted of five males and seven females (31.0 [12.9] years, body mass index of 22.15 [1.6] kg/m2). Facial muscle activity was assessed in several facial regions in each patient for their respective muscle activity utilizing noninvasive surface-derived fEMG. Variables of interest were the average root mean square of three performed muscle contractions (= signal) (µV), mean root mean square between those contraction with the face in a relaxed facial expression (= baseline noise) (µV), and the signal to noise ratio (SNR). A total of 1,709 processed fEMG signals revealed one specific reliable location in each investigated region based on each muscle's anatomy, on the highest value of the SNR, on the lowest value for the baseline noise, and on the practicability to position the sensor while performing a facial expression. The results of this exploratory study may help guiding future researchers and practitioners in designing study protocols and measuring individual facial MUAP when utilizing fEMG. The locations presented herein were selected based on the measured parameters (SNR, signal, baseline noise) and on the practicability and reproducibility of sensor placement.
Full‐face effects of temporal volumizing and temporal lifting techniques
AbstractBackgroundMost injection techniques utilizing hyaluronic acid–based soft tissue fillers have predictable outcomes at the location injected. However, the temporal region has been identified to have aesthetic effects beyond the temple.AimsTo identify and quantify the panfacial aesthetic effects of three different temporal injection techniques.Patients/MethodsThe medical records of nine female and five male Caucasian patients with a mean age of 50.9 ± 11.9 years were retrospectively reviewed for the effects of these techniques: supraperiosteal, interfascial, and subdermal. Panfacial effects were evaluated by the semiquantitative assessment of aesthetic scores for the temple volume, the temporal crest visibility, the lateral orbital rim visibility, the position of the eyebrows, the severity of lateral canthal lines, the midfacial volume, and the contour of the jawline.ResultsThe supraperiosteal injection technique had the greatest influence on improving the temporal volume (25.0%), the temporal crest (33.3%), and the lateral orbital rim visibility (31.0%) scales but had no effects in other facial regions. The interfascial injection technique revealed good effects on improving temporal hollowing (23.3%) but had an even greater effect on the crow's feet (26.8%) and on the position of the eyebrow (33.3%). The subdermal injection technique had its greatest effects in the lower face by improving the contour of the jawline (26.8%) followed by the improvement of the lower cheek fullness scale (14.3%).ConclusionFuture injection algorithms could utilize all three injection techniques together as one multi‐layer injection approach with a tailored proportion of each technique based on the aesthetic needs of the patient.