Ciliary part of retina
Pars ciliaris retinae
- Related terms: Nonvisual retina: Ciliary part of retina
Definition
The ciliary part of nonvisual retina lines the inner surface of the ciliary body, extending anteriorly from the ora serrata, which marks the transition from the photosensitive retina, to the posterior surface of the iris.
Histologically, the ciliary part of retina consists of two epithelial layers: an outer pigmented layer that is continuous with the retinal pigment epithelium, and an inner nonpigmented layer that is continuous with the neural retina.
Ciliary epithelium and aqueous humour production
Together, the pigmented and non-pigmented layers of the ciliary part of retina constitute the ciliary epithelium. The surface is characteristically folded into ciliary processes, which significantly increase the surface area. Functionally, this region is highly specialized for aqueous humour production, with the nonpigmented epithelium playing a key role in active secretion.
References
Standring, S. (Ed.). (2015). Eye (Chapter 42). In Gray's anatomy: The anatomical basis of clinical practice (41st ed., pp. 686-696). Churchill Livingstone.