What Is the Choroid?

Located between the retina and sclera, it is a soft, smooth, elastic and vascular brown film. It starts from the serrated edge of the front and ends around the optic nerve; the inner surface is connected to the pigment epithelium of the retina by a very smooth glass membrane, and the outer surface is connected to the sclera by a potential gap, with the subtle choroidal layer The fibrous platelet stretches into the scleral brown blackboard, and blood vessels and nerves pass through it. The choroid is mainly composed of blood vessels, and its thickness often varies greatly depending on the filling state of the blood vessels. According to general measurements, the anterior part of the choroid is thinner, about 0.1 mm, and the posterior part is thicker, about 0.22 mm. Especially thick. The main function of the choroid is to nourish the outer layer of the retina, which is equivalent to the soft-arachnoid that provides nutrition to the brain. Secondly, it can block the light that penetrates the sclera and enters the eye to ensure clear imaging. On the embryology, the choroid is derived from mesoderm and neuroectoderm, the upper choroid space, choroid vascular layer and elastic tissue are from mesoderm; pigment epithelium and inner nine layers of retina are from neuroectoderm. Histologically, the choroid is divided into five layers: the choroid layer, the large blood vessel layer, the middle blood vessel layer, the capillary layer, and the vitreous membrane.

Located between the retina and sclera, it is a soft, smooth, elastic and vascular brown film. It starts from the serrated edge of the front and ends around the optic nerve; the inner surface is connected to the pigment epithelium of the retina by a very smooth glass membrane, and the outer surface is connected to the sclera by a potential gap, with the subtle choroidal layer The fibrous platelet stretches into the scleral brown blackboard, and blood vessels and nerves pass through it. The choroid is mainly composed of blood vessels, and its thickness often varies greatly depending on the filling state of the blood vessels. According to general measurements, the anterior part of the choroid is thinner, about 0.1 mm, and the posterior part is thicker, about 0.22 mm. Especially thick. The main function of the choroid is to nourish the outer layer of the retina, which is equivalent to the soft-arachnoid that provides nutrition to the brain. Secondly, it can block the light that penetrates the sclera and enters the eye to ensure clear imaging. On the embryology, the choroid is derived from mesoderm and neuroectoderm, the upper choroid space, choroid vascular layer and elastic tissue are from mesoderm; pigment epithelium and inner nine layers of retina are from neuroectoderm. Histologically, the choroid is divided into five layers: the choroid layer, the large blood vessel layer, the middle blood vessel layer, the capillary layer, and the vitreous membrane.

Chinese name

Choroid

Location

Between retina and sclera

Contains

Rich blood vessels and pigment cells

colour

Dark brown

Choroid choroid detachment

1. Also called cilio-choroid de-tachment. The connection between the ciliary body and the choroid and the sclera is tightly connected except for the scleral process and the vortex vein, and the other parts are loosely connected to form a potential gap. When the intraocular pressure decreases after surgery or trauma, the choroidal blood vessels The leakage can be caused by dilation; or the choroid is separated from the sclera due to inflammatory exudate and intravitrealized cord pulling, which is called choroid detachment. Choroid detachment is usually associated with ciliary body detachment, which is customarily called choroid detachment. Clinically, choroidal detachment can be divided into two types according to its cause: primary and secondary; according to its fundus morphology, it can be divided into annular, lobular and flat choroidal detachment. In addition to finding the cause of the treatment, the wound should be closed, pressure bandaged, and dilated pupils. If it is not effective, you can make all the mouth on the sclera, release the subchoroidal effusion, and then inject normal saline into the anterior chamber or vitreous body to promote the choroidal reduction.

2. Except that the uveal and sclera are tightly attached at the exit of the vortex vein, the other parts are loosely connected. When the intraocular pressure drops after surgery or trauma, the choroidal blood vessels may leak due to dilation; There is traction in the vitreous, which can separate the choroid from the inner surface of the sclera, forming choroid detachment. This is more common in the elderly after cataract extraction or anti-glaucoma surgery. Inflammation and bleeding can also cause choroid detachment. The clinical manifestations are full bulges around the fundus, which can be spherical, lobed, or ring-shaped. The flat part of the ciliary body detaches at the same time, which affects the production of aqueous humor, making the intraocular pressure unable to recover for a long time. Treatment should first close the wound, pressurize the bandage, and dilate the pupil. If it is not effective, make all mouths on the sclera, release the subchoroidal effusion, and then inject physiological saline into the anterior chamber or vitreous body to promote choroidal reduction.