[External eye muscles and their attachment zones]

Area of Science:

• Ophthalmology
• Anatomy
• Biomechanics

Context:

• Accurate anatomical data of extraocular muscles are crucial for understanding ocular motility and developing surgical techniques.
• Previous studies have provided some measurements, but a comprehensive in situ analysis is valuable.

Purpose:

• To precisely measure the in situ dimensions (length, diameter, thickness) of the human extraocular muscles and their tendons.
• To provide detailed morphometric data for the rectus superior, rectus medialis, rectus inferior, rectus lateralis, levator palpebrae superioris, and oblique muscles.
• To measure the dimensions of the eyeball (bulbus oculi) and cornea.

Summary:

• In situ measurements were performed on 59 orbits, detailing the length, width, and thickness of the levator palpebrae superioris, four recti muscles, and two oblique muscles.
• Average lengths ranged from approximately 31.46 mm (M. obliquus inferior) to 42.13 mm (M. levator palpebrae superioris).
• Measurements of muscle tendons and the dimensions of the bulbus oculi and cornea were also recorded, alongside distances to the optic nerve.

Impact:

• Provides a detailed anatomical reference for ophthalmic surgeons, researchers, and prosthetic eye designers.
• Contributes to a better understanding of the biomechanics of eye movements.
• Establishes normative morphometric data for the human extraocular muscle system.