Botulinum Toxin Increases Eyelid Height More Than Levator Shortening

Upper eyelid ptosis significantly impairs visual fields and patient quality of life, often necessitating surgical intervention on the levator palpebrae superioris. While botulinum toxin is a standard treatment for hemifacial spasm and blepharospasm, iatrogenic ptosis (drooping of the eyelid caused by medical treatment) remains its most frequent complication, occurring in 2.5% to 27% of cases depending on the clinical indication [1, 2, 3]. Conversely, clinicians have utilized the toxin to manage thyroid-related lid retraction, achieving an 84% success rate and an average reduction in marginal reflex distance (the distance between the pupillary light reflex and the eyelid margin) of 2.42 mm [4]. Recent evidence suggests that chemodenervation (the use of neurotoxins to interrupt nerve signaling to specific muscle fibers) of the orbicularis oculi may serve as a minimally invasive alternative to traditional muscle shortening [5, 2, 6]. A new cohort study of 36 patients demonstrates that targeted toxin injection can increase palpebral fissure height by 3.5 mm, significantly exceeding the 1.7 mm improvement observed with conventional surgery [5]. This approach may offer a viable option for patients with mild dysfunction who wish to avoid the risks of scarring and longer recovery times associated with blepharoplasty (surgical repair or reconstruction of the eyelid).