Eyelid Anatomy – Orbicularis Oculi & Subcutaneous Fat

👁 Eyelid Anatomy – Orbicularis Oculi & Subcutaneous Fat

Unlike the rest of the body, the eyelid lacks subcutaneous fat.
Its structure is: Skin – Muscle – Bone/Tissue, instead of the usual layered pattern.

Depending on vertical height, the orbicularis oculi muscle is categorized into:

PositionStructureMuscle Name

Suprabrow	Skin – Orbicularis – Orbital bone	Orbital part
Mid-eyelid	Skin – Orbicularis – Orbital septum	Preseptal part
Eyelid margin	Skin – Orbicularis – Tarsal plate	Pretarsal part

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💡 Muscle Functions

PartFunction

Pretarsal	Involuntary blinking, controls lash position & Meibomian gland (Riolan muscle)
Preseptal	Involuntary blinking, contains ROOF/SOOF fat – used in cosmetic surgery
Orbital	Voluntary blinking – forceful eyelid closure

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💉 Wrinkle Muscles & Botox

In addition to orbicularis, Corrugator and Procerus contribute to wrinkles.

Wrinkle TypeMuscleTreatment

Vertical (Glabellar)	Corrugator	Botox
Horizontal (Nasal bridge)	Procerus	Botox

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✅ Summary Points

• Eyelids have no subcutaneous fat, unlike other skin areas
• Muscle structure and naming vary by position – Pretarsal, Preseptal, Orbital
• Understanding these layers is key for dry eye, entropion, tear troughs, and Botox treatment planning