Orbicularis oculi muscle: Difference between revisions

From WikiMD's Wellness Encyclopedia

CSV import
 
CSV import
 
Line 1: Line 1:
'''Orbicularis oculi muscle''' is a [[muscle]] in the face that closes the [[eyelids]]. It is one of the two major components of the eyelids, the other being the [[levator palpebrae superioris]] muscle. The orbicularis oculi muscle is not just a single muscle, but a group of muscles that work together to close the eye. This muscle is also responsible for the spontaneous blink reflex, which helps to keep the eyes moist and protected.
== Orbicularis Oculi Muscle ==


== Anatomy ==
[[File:Gray379.png|thumb|right|Anatomy of the orbicularis oculi muscle]]


The orbicularis oculi muscle is divided into three parts: the orbital part, the palpebral part, and the lacrimal part. The [[orbital part]] is responsible for forcefully closing the eye, as in a squint. The [[palpebral part]] is responsible for the spontaneous blink reflex. The [[lacrimal part]] helps to drain tears from the eye by pulling on the [[lacrimal sac]], causing tears to flow into the [[nasolacrimal duct]].
The '''orbicularis oculi muscle''' is a complex, circular muscle located in the face, primarily responsible for the movement of the eyelids. It plays a crucial role in facial expression and the protection of the eyes.


== Function ==
=== Anatomy ===
The orbicularis oculi muscle is a sphincter muscle that encircles the eye. It is divided into three distinct parts:


The primary function of the orbicularis oculi muscle is to close the eye. This can happen voluntarily, as in a blink or a squint, or involuntarily, as in the spontaneous blink reflex. This reflex helps to keep the eyes moist and protected from dust and other particles. The muscle also helps to drain tears from the eye.
* '''Orbital part''': This portion surrounds the bony orbit and is responsible for the forceful closure of the eyelids.
* '''Palpebral part''': Located within the eyelids, this part facilitates gentle closure, such as blinking.
* '''Lacrimal part''': Also known as the tensor tarsi, this part is involved in the drainage of tears by compressing the lacrimal sac.


== Clinical significance ==
=== Function ===
The primary function of the orbicularis oculi muscle is to close the eyelids. It is essential for:


Damage to the orbicularis oculi muscle can result in a number of conditions, including [[blepharospasm]], a condition where the eyelids twitch or close involuntarily, and [[lagophthalmos]], a condition where the person is unable to close their eyes completely. Treatment for these conditions can include [[botulinum toxin]] injections, which can help to relax the muscle and reduce symptoms.
* '''Blinking''': Protects the eye from foreign bodies and helps spread tears across the surface of the eye.
* '''Winking''': A voluntary action that involves the contraction of the muscle.
* '''Tear drainage''': Assists in the movement of tears through the lacrimal apparatus.


== See also ==
=== Innervation ===
* [[Facial muscles]]
The orbicularis oculi muscle is innervated by the [[facial nerve]] (cranial nerve VII). The temporal and zygomatic branches of the facial nerve supply the muscle, allowing for its various functions.
* [[Blepharospasm]]
* [[Lagophthalmos]]


[[Category:Muscles of the head and neck]]
=== Clinical Significance ===
[[Category:Facial muscles]]
Dysfunction of the orbicularis oculi muscle can lead to several clinical conditions, including:
[[Category:Eye]]


{{stub}}
* '''Lagophthalmos''': Inability to close the eyelids completely, often due to facial nerve paralysis.
* '''Blepharospasm''': Involuntary, forceful closure of the eyelids, which can be a symptom of various neurological disorders.


== References ==
=== Related Muscles ===
<references />
The orbicularis oculi muscle works in conjunction with other facial muscles, such as the [[levator palpebrae superioris]] and the [[corrugator supercilii]], to facilitate complex facial expressions and eye movements.


== External links ==
== Related Pages ==
* [https://www.ncbi.nlm.nih.gov/pubmedhealth/PMHT0023125/ Orbicularis oculi muscle] at [[PubMed Health]]
* [[Facial nerve]]
* [http://www.anatomyexpert.com/structure_detail/7951/ Orbicularis oculi muscle] at AnatomyExpert
* [[Facial muscles]]
* [[Eyelid]]
* [[Tear film]]


{{Eye anatomy}}
[[Category:Muscles of the head and neck]]
{{Muscles of head and neck}}

Latest revision as of 11:04, 15 February 2025

Orbicularis Oculi Muscle[edit]

Anatomy of the orbicularis oculi muscle

The orbicularis oculi muscle is a complex, circular muscle located in the face, primarily responsible for the movement of the eyelids. It plays a crucial role in facial expression and the protection of the eyes.

Anatomy[edit]

The orbicularis oculi muscle is a sphincter muscle that encircles the eye. It is divided into three distinct parts:

  • Orbital part: This portion surrounds the bony orbit and is responsible for the forceful closure of the eyelids.
  • Palpebral part: Located within the eyelids, this part facilitates gentle closure, such as blinking.
  • Lacrimal part: Also known as the tensor tarsi, this part is involved in the drainage of tears by compressing the lacrimal sac.

Function[edit]

The primary function of the orbicularis oculi muscle is to close the eyelids. It is essential for:

  • Blinking: Protects the eye from foreign bodies and helps spread tears across the surface of the eye.
  • Winking: A voluntary action that involves the contraction of the muscle.
  • Tear drainage: Assists in the movement of tears through the lacrimal apparatus.

Innervation[edit]

The orbicularis oculi muscle is innervated by the facial nerve (cranial nerve VII). The temporal and zygomatic branches of the facial nerve supply the muscle, allowing for its various functions.

Clinical Significance[edit]

Dysfunction of the orbicularis oculi muscle can lead to several clinical conditions, including:

  • Lagophthalmos: Inability to close the eyelids completely, often due to facial nerve paralysis.
  • Blepharospasm: Involuntary, forceful closure of the eyelids, which can be a symptom of various neurological disorders.

Related Muscles[edit]

The orbicularis oculi muscle works in conjunction with other facial muscles, such as the levator palpebrae superioris and the corrugator supercilii, to facilitate complex facial expressions and eye movements.

Related Pages[edit]