Simulating Upper Eyelid Ptosis During Neuromodulator Injections-An Exploratory Injection and Dissection Study

Area of Science:

• Anatomy
• Cosmetic Procedures
• Ophthalmology

Background:

• Aesthetic neuromodulator injections target upper facial rhytids by blocking muscle action.
• Adverse event rates for toxin-induced blepharoptosis range from 0.51% to 5.4% in existing literature.

Purpose of the Study:

• To identify pathways for neuromodulator spread from extra- to intra-orbital areas.
• To understand how injected products affect the levator palpebrae superioris muscle.

Main Methods:

• Anatomical dissections were performed on nine non-embalmed human body donors.
• Colored product was injected into supraorbital and supratrochlear regions using 0.5 cc and 0.1 cc volumes.
• Dissections identified stained anatomical structures to trace product pathways.

Main Results:

• Supratrochlear and supraorbital neurovascular bundles serve as access pathways for intra-orbital spread.
• Eyelid elevator muscle (levator palpebrae superioris) was affected in 19.44% of injections.
• Eyelid involvement occurred exclusively with 0.5 cc injections, not 0.1 cc volumes.

Conclusions:

• Low injection volume (0.1 cc) is crucial for safety.
• Superficial injections in the supraorbital region are recommended.
• Angling the needle away from the supratrochlear foramen minimizes risk when treating glabellar muscles.