New anatomical insights into preventing brow ptosis with botulinum toxin-A use


  • Matt Sandre, MD, FRCPC


Botulinum toxin-A (BTX-A) injections were the most commonly performed  non-surgical procedure in 2020 according to the Aesthetic Plastic Surgery National Databank Statistics. Between 2019 and 2020, the number of neurotoxin injections performed in the United States has risen 1.5 fold from 1,712,994 to 2,643,366. When utilizing BTX-A in the upper face, the incidence of eyebrow ptosis varies widely and has been quoted in the literature at upwards of 20%. This adverse event is not exclusively seen post-treatment of the frontalis muscle but can also occur through inadvertent diffusion of the neurotoxin when treating the glabellar complex. Over the past year, new anatomic considerations to help injectors optimize results and reduce the risk of eyebrow ptosis with frontalis and glabellar BTX-A injections have been published. This paper aims to summarize three such publications which may help to positively impact injectable outcomes in the clinician’s day-to-day practice.  

Author Biography

Matt Sandre, MD, FRCPC

Dr. Matt Sandre is a dermatologist practicing in Toronto, Ontario at the Canadian Dermatology Centre. He attended the University of Western Ontario where he completed an Honours Bachelor of Medical Sciences degree. Dr. Sandre then returned to Western University to obtain a Bachelor of Science in Nursing degree, where he earned the gold medal in his class. He practiced as a pediatric emergency and pediatric oncology nurse prior to attending medical school at McMaster University. He completed his dermatology residency at the University of Toronto where he served as co-chief resident. Aside from working as a community dermatologist, he is currently completing a Clinical Fellowship in Dermatologic Laser Surgery and Aesthetic Dermatology.


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How to Cite

Sandre M. New anatomical insights into preventing brow ptosis with botulinum toxin-A use. Can Dermatol Today [Internet]. 2021 May 1 [cited 2024 Jul. 15];2(2):30–34. Available from: