Anatomy, Head and Neck: Orbicularis Oculi Muscle

Excerpt

The orbicularis oculi muscle, situated just beneath the eyelid skin, is crucial in eyelid movement (see Image. Muscles of the Head, Face, and Neck). This muscle extends from the medial to the lateral canthal region, enhancing the eyelid's structural integrity and functionality. The orbicularis oculi is a sphincter-like muscle arranged concentrically around the upper and lower eyelids. The main function of the muscle is to close the eyelids, and it also assists with tear drainage. The orbicularis oculi has orbital and palpebral sections, each further subdivided to meet specific functional demands.

The orbicularis oculi is a facial expression muscle that may be affected by conditions such as Bell Palsy and blepharospasm. Botulinum toxin injections target this muscle to smooth dynamic periorbital wrinkles. Understanding the orbicularis oculi's normal anatomy and function is essential in treating various eye and cosmetic conditions.