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Cycloplegiaisparalysisof theciliary muscleof theeye,resulting in a loss ofaccommodation.[1]Because of the paralysis of the ciliary muscle, the curvature of the lens can no longer be adjusted to focus on nearby objects. This results in similar problems as those caused bypresbyopia,in which the lens has lost elasticity and can also no longer focus on close-by objects. Cycloplegia with accompanyingmydriasis(dilation of pupil) is usually due to topical application of muscarinic antagonists such asatropineandcyclopentolate.
Cycloplegia | |
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Dilated pupil (mydriasis) caused bycyclopentolateinstilled into both eyes | |
Specialty | Ophthalmology |
Belladonna alkaloids are used for testing the error ofrefractionand examination of eye.
Management
editCycloplegic drugs are generallymuscarinic receptor antagonistssuch asatropine,cyclopentolate,homatropine,scopolamineandtropicamide.They are indicated for use incycloplegic refraction(to paralyze the ciliary muscle in order to determine the true refractive error of the eye) and the treatment ofuveitis.All cycloplegics are alsomydriatic(pupil dilating) agents and are used as such duringeye examinationto better visualize theretina.
When cycloplegic drugs are used as a mydriatic to dilate the pupil, the pupil in the normal eye regains its function when the drugs are metabolized or carried away. Some cycloplegic drugs can cause dilation of the pupil for several days. The ones specifically used by ophthalmologists or optometrists wear off in hours, but when the patient leaves the office strong sunglasses are provided for comfort.
See also
editReferences
editExternal links
edit- 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.PMID25704934.
- van der Hoeve, J.; Flieringa, H. J. (1 March 1924)."Accommodation".British Journal of Ophthalmology.8(3): 97–106.doi:10.1136/bjo.8.3.97.PMC512904.PMID18168370.