Iris sphincter muscle
| Iris sphincter muscle | |
|---|---|
Iris, front view. (Muscle visible but not labeled.) | |
The upper half of a sagittal section through the front of the eyeball. ("Sphincter of pupil" labeled near bottom-center.) | |
| Details | |
| Origin | Encircles iris[1] |
| Insertion | Encircles iris[1] |
| Artery | Long posterior ciliary arteries |
| Nerve | Short ciliary nerves |
| Actions | Constricts pupil |
| Antagonist | Iris dilator muscle |
| Identifiers | |
| Latin | musculus sphincter pupillae |
| TA98 | A15.2.03.029 |
| TA2 | 6762 |
| FMA | 49157 |
| Anatomical terms of muscle | |
The iris sphincter muscle (pupillary sphincter, pupillary constrictor, circular muscle of iris, circular fibers) is a muscle in the part of the eye called the iris. It encircles the pupil of the iris, appropriate to its function as a constrictor of the pupil.
The ciliary muscle, pupillary sphincter muscle and pupillary dilator muscle sometimes are called intrinsic ocular muscles[2] or intraocular muscles.[3]
- ^ a b Gest, Thomas R; Burkel, William E. (2000). "Anatomy Tables - Eye". Medical Gross Anatomy. University of Michigan Medical School. Archived from the original on 2010-05-26..
- ^ Kels, Barry D.; Grzybowski, Andrzej; Grant-Kels, Jane M. (March 2015). "Human ocular anatomy". Clinics in Dermatology. 33 (2): 140–146. doi:10.1016/j.clindermatol.2014.10.006. PMID 25704934.
- ^ Ludwig, Parker E.; Aslam, Sanah; Czyz, Craig N. (2024). "Anatomy, Head and Neck: Eye Muscles". StatPearls. StatPearls Publishing. PMID 29262013.