Abstract Background Injectable soft tissue fillers are used on a global scale for a variety of aesthetic indications. Despite their widespread use, there is a dearth of information regarding needle deformation following injection procedures. Repeated injections with the same needle could lead to progressive needle tip deformation, potentially resulting in decreased precision and increased patient discomfort. Objectives The objective of this study was to quantify the magnitude of needle tip deformation utilizing scanning electron microscopy (SEM) image analysis. Methods An observational study was performed evaluating 4 differently sized needles following soft tissue filler injections for 5 different aesthetic indications (zygomatic arch, infraorbital, midcheek, nasolabial sulcus, and perioral) in patients aged 36 to 64 years. Following treatment, each needle was visualized and imaged through SEM, and the percentage of deformation in relation to the total amount of needle tip surface was calculated. Results The factor most influencing needle tip damage was revealed to be the number of injection passes, ie, dermal transitions. Per injection procedure, an increase in needle tip damage of 4.7% occurred. Touching the bone deformed the needle tip by 9.6% and an increase in needle size resulted in 0.13% more damage. Conclusions To the authors’ knowledge, this is the first SEM investigation to provide objective evidence for the deformation of needle tips after repeated facial soft tissue filler injections. These data may help improve patient safety and comfort during these minimally invasive procedures. Level of Evidence: 3
Respecting upper facial anatomy for treating the glabella with neuromodulators to avoid medial brow ptosis—A refined 3‐point injection technique
AbstractBackgroundCurrent injection algorithms for treating the glabella rely on a five‐ or seven‐point injection technique with possible medial eyebrow ptosis and lateral eyebrow elevation as undesirable outcomes.ObjectiveThe objective of this study was to investigate the efficacy and safety profile of a refined 3‐point injection technique targeting horizontal and vertical glabellar lines.MethodsA total of n=105 patients (27 males and 78 females) with a mean age of 40.90 ± 9.2 years were investigated. The injection technique relied on targeting the muscular origin of the procerus and the corrugator supercilii muscles exclusively. The time of effect onset and the injection‐related outcome 120 days after the treatment was evaluated using the 5‐point glabellar line severity scale.ResultsThe onset of the neuromodulator effect was on average 3.5 ± 1.5 days. There was no statistically significant difference in the amplitude of movement before or 14 days after the treatment with 2.99 ± 4.4 mm vs. 3.39 ± 3.6 mm (p = 0.149) for the medial head of the eyebrow and with 3.18 ± 4.7 mm vs. 3.33 ± 4.3 mm (p = 0.510) for the lateral head of the eyebrow, respectively.ConclusionIncorporating anatomic concepts into clinical practice for glabellar frown line neuromodulator treatments with the investigated 3‐point injection technique resulted in the absence of adverse events like eyebrow ptosis, upper eyelid ptosis, medial eyebrow ptosis, and lateral frontalis hyperactivity. This technique demonstrated efficacy throughout the 4‐month study period.