Dr. Sebastian Cotofana Shares Unpublished Research Targeting Glabellar Lines with Neurotoxins at SCALE
The 20th anniversary of Music City Symposium for Cosmetic Advances and Laser Education (SCALE) was held from May 14 to 18 at the Grand Hyatt in Nashville, Tennessee. The agenda included an update on neurotoxin related to facial anatomy for improved aesthetic outcomes from Sebastian Cotofana, MD, PhD.
Dr. Cotofana shared unpublished data from a longitudinal clinical study that observed three cycles of glabellar treatment without targeting the forehead: “Continuous Improvement of Frontal Rhytids Following Glabella Only Treatments with Neuromodulators: A Clinical Prospective Pilot Study.” Remarkably, after the third treatment cycle, a statistically significant improvement in forehead wrinkle severity was observed—even though no direct treatment had been applied to the forehead. He hypothesized this was due to muscular rebalancing: Relaxing the depressor muscles allowed the elevator muscles to function more efficiently, subtly enhancing the appearance of untreated areas over time.
Dr. Cotofana noted that the treatment’s cumulative effect on untreated areas stems from the neuromuscular balance established over time. By targeting only the glabellar depressor muscles across successive treatment cycles, the elevated muscle groups are allowed to exert less effort, leading to noticeable improvements in adjacent, untreated regions such as the forehead.
“We saw these changes only in the third treatment cycle, which tells us this is not a one-time chemical diffusion effect,” Dr. Cotofana said. “This is a functional muscular adjustment—something we can use to our advantage when treating patients who are at risk of complications from direct forehead injections.”
Dr. Cotofana also explored the evolving understanding of facial muscular anatomy, emphasizing the dynamic interplay between elevator and depressor muscles in facial expression. The session highlighted novel imaging research and its implications for aesthetic and therapeutic injection strategies.
Dr. Cotofana introduced the concept as a biomechanical tug-of-war between muscle groups that elevate and depress the eyebrows. He reviewed research published in the Aesthetic Surgery Journal in December 2024 titled “Exploratory Analysis of Upper Facial Muscle Interplay During Emotional Expressions: Magnetic Resonance Imaging (MRI) Insights from Young, Caucasian, Toxin-naïve Individuals.”
Researchers utilized high-resolution MRI scans to observe how specific facial expressions activated underlying muscle groups. Participants were asked to maintain expressions such as surprise and anger while being scanned, allowing precise measurements of muscular activity. One of the surprising findings, Dr. Cotofana said, was the co-activation of opposing muscle groups during expressions.
“When you get surprised, both the elevator and the depressor are contracting at the same time,” Dr. Cotofana explained. “This makes sense for precise positioning—gravity and tissue elasticity alone aren’t enough, especially in mature patients.”
A particularly significant finding concerned the corrugator supercilii muscle (CSM), which showed the greatest width increase at the medial third. This aligns with neuromuscular junction studies indicating that most muscle activity concentrates at bony origins, the primary site for toxin activity, providing a refined target for injectors aiming to reduce glabellar lines.
Furthermore, a new framework for axes of movement was presented based on the 2022 research from Plastic Reconstructive Surgery titled “The Anatomy Behind Eyebrow Positioning: A Clinical Guide Based on Current Anatomic Concepts.” Dr. Cotofana categorized vertical and horizontal facial movements, aiding clinicians in identifying the muscles responsible for complex expressions and enhancing injection precision.
He also addressed the challenges of forehead injections due to a complex multi-layered anatomy, noting the presence of eight anatomical layers within 3 mm of tissue, which can inhibit product diffusion. Special attention must be paid to whether injections are superficial or deep to ensure safety and efficacy.
As part of Modern Aesthetics’ Music City SCALE coverage, Dr. Cotofana sat down with Joel L. Cohen, MD, FAAD, for a video interview to discuss the 3-point injection technique. Click here to watch the video interview.