View Full Version : Glaucoma

19th July 2010, 09:43 PM
I know most people aren't too keen on their health. They like to think of themselves as healthy, and even the slightest symptoms they exhibit will be regarded as just a minor glitch. But most of the time, these 'minor glitches' may be cues for diagnosing a more sinister disease. I took the time out to divert from ocular hygiene to tackle this very important issue. The most subtle of all ocular diseases i have come across is GLAUCOMA. The actual definition of glaucoma is highly controversial but i will take a little time to explain exactly what it is. Let us take the case of the condition we normally refer to as hypertension. Ideally, we know it as having 'high blood pressure'. But there are certain signs and symptoms that accompany this condition to which most people ignore till it reaches its adavanced stages. Some of these include dizzinness, fatigue, frequent headaches, either temporal (on your temples) or hemicranial (on one side of the head). In extreme cases, we see a case of an enlarged heart due to the hypertrophy of the cardiac muscles. It is common knowledge that when u excersice your muscles, they get larger.. this is a simple case of hypertrophy. The heart is adjusting to the increasing demands on it to actually pump blood through the blood vessels that could either be clogged with plaque or because of weak heart valves that do not allow the cordial flow of blood to distant tissues of the body. Essentially, not all people with large hearts have a disease condition, athletes tend to have large hearts to accomodate their rigorous activities. It is therefore important to investigate people who are not athletic or small in stature but have very large hearts. Now, with that analogy, let us transfer this knowlege to the eye. But before i begin, it is vital that we know the anatomy of the eye to easily understand what goes on in there.
The eye is an organ of sight, and together with the brain and the optic tracts as well as a chain of nervous tissue, they form the visual system. Now, the eye is the first point of contact in the process of 'seeing'. The eye as we see it is a globe-like structure embedded in a socket, and it is composed of tissues. The globe-like structure of the eye is maintained by the fluids in the eye. the main compartments in the eye which store these fluids are the anterior or aqueous chamber and the posterior chamber. The anterior chamber contains what we call the aqueous humor, and its found between the transparent front part of the eye called the cornea and the lens. Its function is to maintain the shape of the eyeball, and as well as provide nourishment for the anterior segments of the eye since they do not have blood vessels. The posterior chamber on the other hand is made up of more dense fluid called the vitreous humor. The vitreous actually forms the bulk of the eye, and is found between the posterior (back) surface of the eye lens and the retina. The retina is forms part of the neural tissue that conducts impulses that generate the sensation of sight, and i will get to that in a minute.
Unlike the vitreous, the aqueous humor is constantly produced and drained out of the eye, because it contains metabolites that were produced by the surrounding tissues of the posterior surface of the cornea as well as the lens. However, the rate at which it is constantly produced must be proportional to the rate at which it is drained. If too much is produced than drained, we begin to have a condition called OCULAR HYPERTENSION, and pressure in the eye increases. The reverse is called OCULAR HYPOTENSION. However, the problem lies with the increased pressure within the eye. As pressure builds within the eye, pressure is also exerted on the optic nerve of the eye which is the point at which the optic nerve exits the eye. It is a somewhat delicate tissue, and the pressure it endures most frequently damages it! Most often than not, some people with ocular hypertension don't feel its effect, but it is considered a risk factor for having glaucoma. So what then is glaucoma? It is a condition with an increased ocular hypertension, coupled with a peripheral visual field loss (as a result of the damage caused to the neural rim tissue, the optic nerve). It is for this reason that it is considered a very subtle disease, because it steals your vision peripherally and makes it quite unnoticeable till it has reached its advanced stages. That is why it is essential to have regular and frequent eye examinations. In the next post I will talk about the signs, symptoms, diagnosis and treatment of glaucoma. Hope you have found this post informative and interesting to read. Remember, your health matters, protect it!!!