Pars plana

The pars plana (Latin: flat portion) is part of the ciliary body in the uvea (or vascular tunic), the middle layer of the three layers that comprise the eye. As a part of the ciliary body, it is about 4 mm long, located near the point where the iris and sclera touch and is scalloped in appearance. The pars plana may not have a function in the post-fetal period, making this a good site of entry for ophthalmic surgery of the posterior segment (pars plana vitrectomy).

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