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Ultrasound-guided Botulinum Toxin-A Injections: A Method of Treating Sialorrhea
Published on: November 9, 2016
Single-Point Periorbital Botulinum Neurotoxin Injection and Its Potential Role in Hematoma Risk Reduction: A
Alexander Gardetto1,2, Luis Thaler-Wolf1
1Division of Plastic, Aesthetic and Reconstructive Surgery with Hand Surgery, Brixsana Private Clinic, Via Julius Durst 28, 39042 Bressanone, Italy.
Abstract:
Botulinum neurotoxin type A (BoNT-A) injection for lateral canthal rhytids is among the most frequently performed nonsurgical aesthetic procedures; however, procedure-related hematoma and ecchymosis remain frequent local adverse events associated with the multiple puncture sites required in the conventional three-point technique. This prospective single-center preliminary clinical observation evaluated a single-point intramuscular injection technique designed to reduce percutaneous vascular-layer penetrations while preserving treatment territory, dose, and intramuscular target localization. A total of 152 consecutive patients (104 female and 48 male) underwent bilateral treatment between May 2025 and May 2026 using a single skin entry point per side, positioned 10-15 mm caudal to and 10 mm temporal to the lateral canthus, followed by 18-20 mm intramuscular advancement within the lateral orbicularis oculi and continuous retrograde infusion of 12 U of onabotulinumtoxinA per side. Post-procedural assessment after injection demonstrated small unilateral ecchymosis in 2 of 304 treated sides (0.66%; Clopper-Pearson 95% Confidence Interval (CI), 0.08-2.36%). After the 10-day follow-up, no persistent bruising or other adverse events were reported, and all patients confirmed satisfaction with the treatment. At the structured one-year follow-up, the satisfactory reduction in dynamic lateral canthal rhytids and continued patient satisfaction with the treatment were confirmed, while a subset elected to return for a subsequent treatment session during the observation period. By reducing bilateral percutaneous venous-layer penetrations from six to two while maintaining dose and treatment-territory equivalence, the single-point intramuscular technique may represent a structurally coherent refinement of established BoNT-A treatment concepts for lateral canthal rhytids. Because this was an uncontrolled preliminary clinical observation, the observed rate should be interpreted as descriptive only; any potential reduction in hematoma risk remains hypothetical.