Pars plicata

The pars plicata is the folded and most anterior portion of the ciliary body of an eye. The ciliary body is a part of the uvea, one of the three layers that comprise the eye. The pars plicata is located anterior to the pars plana portion of the ciliary body, and posterior to the iris. The lens zonules that are used to control accommodation are attached to the pars plicata.

The pars plicata is the portion of the ciliary body that is responsible for producing aqueous humor, the fluid of the anterior chamber.^[1] The production of too much aqueous humor, or reabsorption that occurs too slowly, can lead to increases in the pressure within the eye.

References

↑ Kumar, Vinay (2007). "Eye, Anterior Segment". Robbins basic pathology (8th ed.). Philadelphia: Saunders/Elsevier. ISBN 978-1416029731.

Anatomy of the globe of the eye

Fibrous tunic (outer)

Sclera	Episcleral layer Schlemm's canal Trabecular meshwork

Cornea	Limbus layers Epithelium Bowman's Stroma Descemet's Endothelium

1:posterior segment 2:ora serrata 3:ciliary muscle 4:ciliary zonules 5:Schlemm's canal 6:pupil 7:anterior chamber 8:cornea 9:iris 10:lens cortex 11:lens nucleus 12:ciliary process 13:conjunctiva 14:inferior oblique muscule 15:inferior rectus muscule 16:medial rectus muscle 17:retinal arteries and veins 18:optic disc 19:dura mater 20:central retinal artery 21:central retinal vein 22:optic nerve 23:vorticose vein 24:bulbar sheath 25:macula 26:fovea 27:sclera 28:choroid 29:superior rectus muscle 30:retina

Uvea/vascular tunic (middle)

Choroid	Capillary lamina of choroid Bruch's membrane Sattler's layer

Ciliary body	Ciliary processes Ciliary muscle

Iris	Stroma Pupil Iris dilator muscle Iris sphincter muscle

Retina (inner)

Layers	Inner limiting membrane Nerve fiber layer Ganglion cell layer Inner plexiform layer Inner nuclear layer Outer plexiform layer Outer nuclear layer External limiting membrane Layer of rods and cones Retinal pigment epithelium

Cells	Photoreceptor cells (Cone cell, Rod cell) → (Horizontal cell) → Bipolar cell → (Amacrine cell) → Retina ganglion cell (Midget cell, Parasol cell, Bistratified cell, Giant retina ganglion cells, Photosensitive ganglion cell) → Diencephalon: P cell, M cell, K cell, Muller glia

Other	Macula Foveola Fovea centralis Parafovea Perifovea Optic disc Optic cup

Anterior segment

Posterior segment

Vitreous humour

Other

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