The Relationship Between Glabellar Contraction Patterns and Glabellar Muscle Anatomy: A Magnetic Resonance Imaging–based Study

Summary: This study used MRI to investigate whether variations in glabellar muscle anatomy influence different glabellar contraction patterns, which are commonly used to guide neuromodulator injection strategies. Among 34 healthy young Caucasian individuals, no significant differences were found in muscle measurements (length, thickness, width, surface area) across the five contraction pattern types. Sex was the only significant variable, with males generally having larger muscle parameters. Overall, the findings suggest that glabellar contraction patterns are not strongly linked to underlying muscle anatomy, questioning the consistency of using these patterns to guide injection algorithms.