For Doctors in a Hurry
- Clinicians require effective, minimally invasive alternatives to traditional surgical shortening of the levator palpebrae superioris muscle for treating ptosis.
- The study compared botulinum toxin injections against traditional surgery in a cohort of 36 patients with eyelid muscle weakness.
- Injections yielded a 3.5 mm improvement in palpebral fissure height, compared to 1.7 mm in the surgical control group.
- The researchers concluded that toxin injections offer a viable, less invasive option with fewer adverse reactions and faster recovery times.
- Physicians may consider this approach for patients with mild dysfunction who prefer to avoid surgical intervention for their ptosis.
Redefining the Management of Eyelid Ptosis
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).
Comparing Chemodenervation to Surgical Shortening
The researchers conducted a cohort study involving 36 patients diagnosed with weakness of the levator palpebrae superioris, the primary muscle responsible for elevating the upper eyelid. Ptosis, defined as the drooping of the upper eyelid resulting from dysfunction of this muscle, can occur as an isolated clinical finding or as a secondary manifestation of systemic conditions such as myasthenia gravis (an autoimmune neuromuscular disease characterized by muscle weakness). While traditional management of ptosis typically relies on surgical interventions, this study evaluated the efficacy and safety of a minimally invasive alternative: botulinum toxin injections into the orbicularis oculi muscle. The study population was divided into two distinct cohorts, with an experimental group receiving the toxin injections and a control group undergoing traditional levator palpebrae superioris muscle shortening surgery. The primary endpoints of the investigation focused on functional and subjective improvements following treatment. The researchers measured changes in the palpebral fissure height (the vertical distance between the upper and lower eyelid margins) alongside standardized visual scores and patient satisfaction ratings. To assess the clinical utility and safety profile of each intervention, the authors also tracked secondary outcomes, including the incidence of adverse reactions and the duration of the recovery period. By comparing these metrics, the study aimed to determine if chemodenervation of the orbicularis oculi, which normally acts to close the eyelid, could effectively counteract the weakness of the levator palpebrae superioris and provide a viable alternative to invasive surgical shortening.
Superior Aperture Gains and Reduced Complications
The quantitative results of the study demonstrated a clear divergence in functional outcomes between the two treatment modalities. Patients in the experimental group who received botulinum toxin injections achieved a significant improvement in palpebral fissure height of 3.5 mm, more than doubling the 1.7 mm improvement observed in the control group undergoing traditional levator shortening surgery. This increase in the vertical opening of the eye translated directly into clinical benefits, as the experimental group showed a significant improvement in visual function compared to the surgical cohort. These objective gains in the visual field suggest that chemodenervation of the orbicularis oculi (the muscle responsible for eyelid closure) effectively mitigates the functional deficit caused by levator palpebrae superioris weakness by reducing the antagonistic force against the weakened elevator muscle. Subjective measures further supported the use of the toxin, with patient satisfaction scores reaching higher levels in the experimental group than in the surgical group. The researchers noted that this preference was largely attributed to the non-invasive nature of the injections and the significantly shorter recovery period required for patients to return to their baseline activities. From a safety perspective, the incidence of adverse reactions was lower among those receiving botulinum toxin. Specifically, the experimental group experienced fewer complications such as scarring, which is a common risk associated with the incisional nature of traditional levator palpebrae superioris muscle shortening. Clinically, these findings suggest that botulinum toxin injection may represent a viable minimally invasive alternative for carefully selected patients. The authors highlighted its utility particularly for those presenting with mild dysfunction or for individuals who wish to avoid the risks and downtime of invasive surgery. Because the treatment provides significant improvements in palpebral fissure height and visual function with a faster recovery, it offers a practical option for early stage management. While the study underscores the immediate benefits of this approach, the researchers concluded that further investigation is necessary to determine the long term effectiveness of toxin injections compared to the permanent structural changes achieved through surgery.
References
1. Wang B, Wei X, Qi H, Bao X, Hu M, Ma J. Efficacy and safety of botulinum neurotoxin in the treatment of hemifacial spasms: a systematic review and meta-analysis.. BMC neurology. 2024. doi:10.1186/s12883-024-03883-x
2. Cavallini M, Cirillo P, Fundarò SP, et al. Safety of botulinum toxin A in aesthetic treatments: a systematic review of clinical studies.. Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.]. 2014. doi:10.1111/dsu.12463
3. Issaho DC, Carvalho FRDS, Tabuse MKU, Carrijo-Carvalho LC, Freitas DD. The Use of Botulinum Toxin to Treat Infantile Esotropia: A Systematic Review With Meta-Analysis.. Investigative ophthalmology & visual science. 2017. doi:10.1167/iovs.17-22576
4. Zong AM, Giannakakos VP, Patton CD, Barmettler A. Botulinum Toxin Treatment in Thyroid Eye Disease: A Systematic Review and Meta-analysis.. Ophthalmic plastic and reconstructive surgery. 2025. doi:10.1097/IOP.0000000000002852
5. Lu S, Wei Q, Ma J, et al. Orbicularis Oculi Toxin Injection for Treating Levator Palpebrae Superioris Weakness: Clinical Effect and Safety in a Cohort Study.. Aesthetic surgery journal. 2026. doi:10.1093/asj/sjag076
6. Matarasso SL, Matarasso A. Treatment Guidelines for Botulinum Toxin Type A for the Periocular Region and a Report on Partial Upper Lip Ptosis following Injections to the Lateral Canthal Rhytids. Plastic & Reconstructive Surgery. 2001. doi:10.1097/00006534-200107000-00033
