Continuous Improvement of Frontal Rhytids Following Glabella Only Treatments With Neuromodulators—A Clinical Prospective Pilot Study

While traditionally focused on treating glabellar and forehead rhytids through direct neuromodulator injections, recent findings on the biomechanics of facial muscles suggest that glabellar treatments alone may influence forehead wrinkles by altering the dynamic balance between depressor and elevator muscles. To evaluate whether glabellar-only neuromodulator treatments can reduce forehead wrinkle severity without direct injections into the frontalis muscle. This prospective, interventional study included 18 participants with moderate to very severe glabellar lines. Neuromodulator (AbobotulinumtoxinA; 37.5 sU (= 15 IU)) injections were administered exclusively in the glabella at three intervals over 7 months. Glabellar Severity Scale (GLSS), Forehead Wrinkle Scale (FWS), Frontal Skin Displacement (FSD), and Eyebrow Position Scoring (EPS) were assessed at baseline and 30 days after each cycle. GLSS scores significantly improved across treatment cycles (baseline: 3.0; post-third cycle: 1.0; p < 0.001). FWS improved from 3.0 at baseline to 1.0 after the third cycle (p = 0.005), while FSD showed a significant reduction from 37.2 mm to 17.9 mm (p < 0.01). No changes in eyebrow position were detected following EPS assessment. Glabellar-only neuromodulator treatments with 37.5 sU (= 15 IU) effectively reduced forehead rhytid severity, likely by altering the balance between depressor and elevator muscles. This approach minimizes risks associated with direct frontalis injections and offers a novel strategy for forehead rejuvenation. Moreover, the observed progressive improvement across treatment cycles suggests that this strategy may continuously enhance aesthetic outcomes over time, supporting the rationale for maintenance treatments at regular intervals.