Botulinum Toxin to Treat Horizontal Forehead Lines: A Refined Injection Pattern Accommodating the Lower Frontalis

Abstract

Background When treating horizontal forehead lines with botulinum toxin type A the traditional approach requires that injection points should stay 1.5 to 2 cm above the orbital rim to avoid brow ptosis. Failure to treat the lower frontalis may potentially cause worse rhytides in the lower forehead. Objectives The aim of this study was to present a refined injection pattern accommodating the lower frontalis and evaluate its clinical efficacy and safety. Methods Patients were categorized into 4 types according to the patterns of their forehead wrinkles. Moderate and severe wrinkles in the upper forehead were treated by the “safe zone” technique. Mild wrinkles and rhytides in the lower forehead were treated by the Microbotox technique. Standard photographs and measurements were taken before and after treatment. The effect on wrinkle reduction and changes in brow heights were assessed. Results In total, 330 treatments were followed up in the clinic, and 246 treatments were followed up by telephone. Among the 330 treatments, 213 were evaluated in our clinic 2 to 4 weeks later, and the patients who received these treatments were recruited for effect evaluation and brow height measurements. The posttreatment severity of forehead wrinkles was significantly reduced (P < 0.05), and brow heights remained unchanged (P > 0.05). No severe adverse events were documented. Patient satisfaction was quite high. Conclusions The refined injection pattern is an effective and safe technique to treat horizontal forehead lines. The Microbotox technique enables treatment of the lower frontalis without changes in brow position. Level of Evidence: 3

Forehead Movement Discrepancies After Botulinum Toxin Injections: A Review of Etiology, Correction, and Prevention

“…4,12 Traditional teaching is that frontalis injection points should remain 1.5 to 2 cm above the orbital rim to avoid brow ptosis; however, this can cause worsening of lower forehead rhytides. 5 Recommendations for correction in the literature: Inject a small amount (1-4 units) of botulinum toxin into the inferior frontalis. This can be safely performed with an approach similar to our preferred injection technique as described below or the "microbotox" technique used by Zhang and colleagues for lower forehead rhytides in which a maximum of 2 units of onabotulinumtoxin A in women or 4 units in men is distributed over 10 to 20 intradermal injection points in the lower forehead.…”

“…This can be safely performed with an approach similar to our preferred injection technique as described below or the "microbotox" technique used by Zhang and colleagues for lower forehead rhytides in which a maximum of 2 units of onabotulinumtoxin A in women or 4 units in men is distributed over 10 to 20 intradermal injection points in the lower forehead. 5…”

“…2 However, it is one of the most difficult areas to neuromodulate, because of significant interplay between the frontalis and neighboring muscle groups, as well as varying frontalis muscular dynamics which can be unmasked with uneven immobilization and result in over recruitment of the nonparalyzed portions of the muscle. [3][4][5] Here, we review underlying forehead anatomy, common forehead movement discrepancies arising from neuromodulation and how to correct them, as well as injection techniques and patient-specific factors that should be considered before neuromodulation to aid in prevention of forehead movement discrepancies.…”

Botulinum toxin complications in registered and off‐label aesthetic indications

“…Patients have to be cautiously preselected for forehead injections. Frontalis should be under‐dosed, and BTXA should not be injected closer than at least 2 cm to the eyebrows 2,47 …”

“…Frontalis should be under-dosed, and BTXA should not be injected closer than at least 2 cm to the eyebrows. 2,47 Once happened, eyebrows ptosis lasts about 3-4 weeks. Exercising the muscle by trying to elevate the eyebrows against pressure applied by a hand laid on a forehead may shorten period of inconvenience.…”