How the Eye Works – What to Know About Your Vision

As long as they are working fine, your eyes are probably a part of your body that you take for granted. We all feel that way, but have you ever stopped to think about how the eye works and what you need to know about your vision, to preserve it for a lifetime? Your eyes are among the most vulnerable organs of the body, with little to protect them from hazards. To understand how best to upkeep your vision, you need to know how your eyes work and what can potentially go wrong with them.

Here is a quick rundown of functions of the main parts of the human eye:

The Cornea

The cornea is the outer layer of the human eye. When rays of light reach the eye, it first meets with the cornea, which aids in focusing the incoming light. The cornea is important to a person’s overall visual acuity because it accounts for most of your overall eyesight. Interestingly, and somewhat uniquely in the human body, no part of the vascular system reaches the cornea, so tear ducts and fluids produced in the anterior chamber (which is deeper within the eye) give the cornea its only nourishment.

As an unshielded surface of the body, the cornea is subject to some serious health concerns which have a strong bearing on overall vision. Cornea diseases and disorders include:

  • Corneal abrasions
  • Corneal ulcers
  • Keratitis (inflammation of the cornea)

The cornea is generally very resilient to minor abrasions; however, serious traumas or any signs of cloudiness of the eye demands immediate medical attention. As the starting point for visual information in human neurological processes, the cornea is a critical organ that demands prompt and proper care at the first sign of trouble.

In non-life threatening eye care treatments, the cornea performs an important role in treating common sight problems. The shape of the cornea itself can affect whether or not a person needs to wear corrective lenses. Refractive eye surgery is a common procedure that can improve natural eyesight, potentially without the need for eyeglasses or contacts.

The Iris

The iris rests just underneath the cornea. The iris is a circular elevation that dictates the diameter of the pupil. The iris gives your eyes their distinctive coloration. The iris consists of two layers: the stroma and, beneath that, pigmented cells. The muscular system connects to the stroma of the iris, allowing it to dilate the pupil dynamically.

Aside from injury, the major health concern for the iris is conjunctivitis – commonly called pink eye – which can indicate infection, inflammation, or acute glaucoma.

The Pupil

The pupil is the circular black hole at the center of the eye. The iris regulates the amount of light coming into the pupil. When light enters your eye, a neurological response feeds signals into the oculomotor nerve which causes the iris to expand or contract accordingly.

The pupil is subjected to nerve damage, which can cause chronically dilated pupils in some cases. Conversely, some people experience chronically narrowed pupils, which makes it very difficult to see in the dark.

The Inner Eye – the Lens, the Vitreous Humor, and the Retina

The eye’s lens performs an important function. The lens allows you to focus on small details. The lens is also a trouble spot for aging adults, as it is the area of the eye which loses elasticity with age, resulting in cataracts.

The vitreous humor is the gel-like substance of that eye which gives your eyeballs their unique shape. As you age, floaters, or imperfections in the static fluid of the vitreous humor, can occur. These are sometimes visible to the affected person.

Although, the brain sometimes learns to “ignore” floaters, in extreme cases, a laser procedure called vitreolysis is occasionally necessary to evaporate them. The vitreous humor is also prone to shrinkage during the aging process, which can lead to detachment of the vitreous humor from the retina, requiring surgery.

The retina is the back portion of the human eye. It receives the focused visual information from the outer parts of the eye and, importantly, translates that information into neurological information. The retina is also subject to the following diseases and disorders:

  • Macular degeneration
  • Cone-rod dystrophy (CORD)
  • Retinoblastoma (cancer of the retina)
  • Retinitis pigmentosa

As an important hub for translating visual stimuli into neurological information, any problem with the retina calls for a consultation with a qualified ophthalmologist.

Visit Dr. Ghosheh for An Eye Exam

What most patients do not realize is that their eyes do more for their bodies than they imagine. If you are looking for more information regarding eye care exams and services, please contact the Advanced Eye Medical Group and we will help guide you in the right direction.