Eye Anatomical Terms Explanation - LESSON 266

In the travel of learning free medical transcription course, we are going to learn about anatomical terms explanations of eyes. As a medical transcriptionist student, you should know about all the anatomy and physiology, not like a medical student for surgical purpose, but you should know something basic 

information about them. We explained something in the prior lesson about this topic about what is accomodation, anterior chamber, aqueous humor, biconvex, layer of choroid, ciliary body, cones, conjuctiva, cornea, fovea centralis, fundus of the eyes, lens, iris, macula, optic chiasm, and optic disk. In this lesson, we will learn about, optic nerve, posterior chamber, pupil, refraction, retina of the eyes, rods, sclera, vitreous chamber, vitreous humor one by one. Okay.

Optic Nerve: The other name of optic nerve is cranial nerve 2, which receives and delivers eye sight messages to the brain from the part of cerebral cortex from the retina of the eye.

Posterior Chamber: This is a narrow area behind the iris, which contains a liquid called aqueous humor. Posterior chamber is situated in the front side of the lens's suspensory ligament, as well as ciliary processes.

Pupil: This is a dark hole that situated at the central portion of the iris. The light passes through the eye is taken in by the tissues present here. In simple, pupil is the entrance of the eye.

Refraction: An image is formed inside the eye through the process of refraction. By way of lens and cornea, the entered light rays from the pupil are bended and targeted towards the retina and so we can feel visual sensation of lights.

Retina: This is a tissue lining that is responsive to the light waves that is present inside surface of the eye. Retina consists of color receptor cells called cones and rods.

Rods: These are cells present inside the eye that are photoreceptor cells. Rods are present inside the retina. These rods absorbs mainly black and white waves and so we can see at night.

Sclera: Each eye contains an external coat in the eyeball called sclera, which is very tough in structure. We can see this portion outside and this is also called as 'white of the eye. This hard layer performs as the protective cover of the eye made up of elastic fibers and collagen.

Vitreous Chamber: This chamber occupies about four fold place in five of the eyeball area. This chamber is present between the retina and the lens.

Vitreous Humor: It is a gel-like material present inside the viterous chamber and named as vitreous humor.

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Anatomical Definitions Of Eye -- Lesson 265

In this post we would come through the definitions shortly.

1. Accommodation: - The adjustment of the eye made normally for looking at objects at different distances. To bring an object into focus on the retina, the lens is made thinner or fatter by the ciliary body.

2. Anterior chamber: -  This is the area behind the cornea and in front of the lens and iris.  Aqueous humor is contained in it.

3. Aqueous humor: - Fluid is produced by the ciliary body and found in the chambers which are anterior and posterior.

4. Choroid layer: - The vascular and middle layer of the eye between the retina and the sclera.

5. Ciliary body: - It is the structure which is on each side of the lens that connects the choroids and the iris. This also contains ciliary muscles, which control the shape of the lens, and secretes aqueous humor.

6. Cones: - The receptor cells which is called photosensitive receptor cells transform light energy into a nerve impulse. Cones are responsible for color and central vision.

7. Conjuctiva: - A delicate membrane lining the eyelids and covering the anterior eyeball.

8. Cornea: - Fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball.

9. Fovea centralis: - The tiny pit or depression in the retina that is the region of clearest vision.

10. Fundus of the eye: - The posterior and inner part of the eye.

11. Iris: - The colored portion of the eye.

12. Lens: - Behind the pupil of the eye, a transparent biconvex body is situated. It bends light rays to bring them into focus on the retina.

13. Macula: - A yellowish region on the retina, lateral to and slightly below the optic disk; and also contains the fovea centralis.

14. Optic chiasm: - The point at which the fibers of the optic nerve cross in the brain.

15. Optic disk: - The region at the bake of the eye where the optic nerve meets with retina. It is the blind spot of the eye because it contains nerve fibers only and there are no rods and cones and thus this is insensitive to light.

                   

In the next post we would learn some more definitions.

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