A Study on the Development of the Uveal Tract.

Jo, Yong Hyun

Original Article

Journal of the Korean Ophthalmological Society 1980;21(3):221-225.
Published online March 1, 1980.

A Study on the Development of the Uveal Tract.

Yong Hyun Jo

Department of Ophthalmology, College of Medicine, Busan National University, Busan, Korea.

포도막의 발육에 대하여

조용현(Yong Hyun Cho)

Abstract

The embryology of the various parts of the human body, especially that of the eye, has its years-long history. But in recent years, the embryological study of the eye didn't attract much attention of the investigators. Lately the author had an opportunity to obtain the eyeballs (54) in the gestational age irom at least 3 months to 10 months. The specimens used were sectioned for tissue microscopy and stained when necessary. I studied the developmental process of the uveal tract, such as ciliary body, ciliary process and ciliary muscle the marginal sinus and its relationship between pupillary muscles and pigmentation of the iris epithelial vessels of choroid and pupillary membrane. The result obtained are as follows: 1. The ciliary body appeared at the 12th week of embryonic life and the ciliary processes were formed at the 16th week of embryonic life. At the 36th week of embryonic life, the ciliary body was divided into the pars plana and pars plicata. Condensation of the ciliary muscle cells appeared at the 12th week and continued its development until birth. 2. The marginal sinus appeared at the 12th week of embryonic life and reached the maximum in its size at the 16th week, it disappeared completely at the 28th week of embryonic life. 3. At the 16th week of embryonic life, pigmentation of the iris pigment epithelium began from the outer wall of the marginal sinus and fully developed pigmentation at the 28th week, at the same stage, the mesodermal tissues, vessels and fibroblasts, growing into the muscle stump. 4. At the 12th week of embryonic life, small vessels made their appearance in the choroid By the 20th week of embryonic life, large vessels developed and the choroid showed a fully matured vascular appearance. 5. The pupillary membrane remained until the 32nd week and completely disappeared at the 36th week of embryonic life. These findings suggested that the size of marginal sinus closely related to development of the pupillary muscles and pigmention of the iris pigment epithelium.