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What is glaucoma?

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Dr. Sylvester Ikhisemojie

Glaucoma is an eye disease that is usually linked to the build-up of pressure inside the eyeball, a kind of hypertension really, but one that is confined to the eye and called intra-ocular pressure. When it is raised beyond the normal range, glaucoma results. The eyeball is like a football or a basketball which requires a certain amount of pressure to maintain its shape.

When pressure builds up too much within either of them, there is a pressure valve which gives and the pressure reduces. Everyone who plays either game would appreciate this valve. The eyeball has no such pressure release system.  The main cause of glaucoma is the failure of the eye to maintain the desired balance between the amount of fluid which the eye produces and the amount which drains out of it. This results in an accumulation of excess fluid called the intraocular fluid, and when the tension caused by its accumulation within the eye rises severely, glaucoma results.

Despite the absence of a pressure release mechanism within the eyeball, it must continue to maintain its shape by developing a strict mechanism for balancing production and drainage of intraocular fluid. When this fails, vision can become impaired or lost. A sustained build-up in pressure against the optic nerve develops from this accumulation until its fibres become permanently damaged and blindness results. In order to properly understand how glaucoma comes about, it is important to appreciate how the eyeball is made and how this fluid moves through the eye. The clear fluid inside the eye is produced by the ciliary body, a small structure with a circular shape which is found behind the iris. The iris is the coloured ring in the centre of the eyeball that has several colours in various people; brown, green, blue, gray and hazel or even black.

The fluid is known as the aqueous humour and it flows behind that iris to pass through the pupil. The pupil is the dark hole in the centre of the iris that controls how much light gets into the eye. It therefore determines the brightness of various images but also provides a gateway for the aqueous to flow into the anterior chamber. That is the space between the front of the iris and the back of the clear, whitish, sclera. From here, the aqueous humour passes out of the eye through a drainage angle. When anything obstructs that drainage angle and the flow of fluid through it, there is a rise in intraocular pressure thus leading to glaucoma. Such obstruction can often result from injuries to the eye as well.

Glaucoma is a leading cause of blindness especially in sub-Saharan Africa. In the world as a whole, it is the second most common cause of blindness.  Glaucoma is usually, but not always, the result of an abnormally high pressure inside the eye. Some people without an increase in eye pressure may develop progressive damage to their optic nerve. The cause of this variant is not known but it is also referred to as the normal tension glaucoma. However, a lack of blood flow to the optic nerve may be a factor in causing this type of glaucoma. This is therefore one of the five variants of glaucoma known to exist. The others are as follows;

1) The open angle glaucoma or the chronic type of the disease is often sublime in its manner of onset and may thus not have any of the typical symptoms. There are no signs except a gradual loss of vision. Very often, the loss is so slow in progression that irreparable eye damage can occur before the cause of the problem is obvious. Unfortunately, this is the most common variant of the eye disease.

2) Angle closure glaucoma usually has a short rapidly progressing pattern. There is a sudden blockage in the flow of the aqueous humour and the equally rapid build-up in the volume and pressure of the intraocular fluid. As a result, severe, rapid and painful increase in the eye pressure develops together with associated nausea and blurred vision. When these features are observed, a doctor should be seen immediately because this is an emergency.

3) Secondary glaucoma is usually a side-effect of an injury to the eye or another eye condition such as cataracts or tumours in the eye. Steroid preparations used for a variety of purposes can also cause this kind of glaucoma.

4) Congenital glaucoma is described in a situation when children are born with a defect in the angle of their eye which slows down the rate of drainage of the eye or prevents that completely from happening. Such an eye will produce tears excessively and develop a cloudy vision. It can also become excessively sensitive to light and it is a condition that can run in families.

The people at the most risk for developing glaucoma are elderly people over the age of 60 years. The risk is further aggravated with each additional yearly increase in age. In Africans, that risk begins at least two decades earlier, from as young as 40 years. That is also true for black Americans. It is also known that people who suffer from diabetes, hypertension and heart disease are often more likely to have glaucoma. It is therefore clear that the medical status of any newly diagnosed case should be determined in order to identify the degree of risk. Individuals with chronic eye problems which may include chronic eye inflammation and previous physical injury or even surgery can also cause this problem.

The diagnosis of this disease follows the sequence of taking the medical history in which all the issues detailed above are highlighted followed by a thorough examination which includes tanometry, a means that measures the eye’s internal pressure. Following this must be the treatment that will alleviate the problem.

Often medications and eye drops may be used alone or in combination to treat the problem. The use of eye drops is more common. The treatment for angle closure glaucoma is surgery to drill openings into the iris and allow the flow of intraocular fluid. This is done by laser iridectomy. More commonly, a procedure called trabeculectomy is performed to create an artificial window in the sclera to rapidly reduce the pressure in the eyeball.

Ask the doctor

Dear doctor, I visited an ENT clinic following a complaint of ringing in both ears and the consultant said he could not find anything abnormal that would warrant treatment and that it is an ageing process. Due to the fact that it is fragmenting my sleep, is there a mild sleeping tablet I can buy over-the-counter to deal with this problem initially, say for two months, before my body gets familiar with this situation? I am 73 years old. 0906xxxxxxx

I greatly sympathise with you sir particularly with respect to the fact that good sleep has been eluding you. There are some mild medications you can obtain to make it easier to get some decent sleep but it is often better that the ENT surgeon who examined you should still be the one who will write out such a prescription for you. I am sure he will listen to your request if you make one. In the alternative, I will urge you to take a mug of warm cocoa drink in the form of Bournvita, Milo or Ovaltine to achieve the same purpose. That has worked for lots of people.

Dear doctor, thank you very much for your response to my last text about the burning sensation under my toe. I don’t have diabetes. Could be due to lumbar spondylosis? I have had leg pain and waist pain in the past but it reoccurs occasionally. What can I do? 0805xxxxxxx

Well, you will have to be examined by a neurologist or an orthopaedic surgeon in order to determine what is wrong with your waist. As for the burning sensation you feel, it could indeed be a complication of lumbar spondylosis in which a nerve root has been pinched between two vertebral bones. An orthopaedic surgeon will be better placed than the former in that case to examine you and have your back X-rayed and/or scanned before any conclusion can be reached with regards to what the possible cause might be. Book an appointment with one as soon as possible.

Dear doctor, I always have pains whenever I am having sex with my man and it is only when I switched to the back style that I feel the pains. What could be the cause of that?                                                                                      0812xxxxxxx

There may be a low grade genital tract infection which a doctor who examines you should be able to determine and offer you the appropriate treatment and the problem will be resolved. If there is no infection, however, it would be because the back position which you noticed to be most often associated with the pain offers your partner an unduly deep penetration thereby causing the pain. If that is the reason, simply stop using that position. It is not everything that is kind to everybody.

Dear doctor, please what are the symptoms of an appendix? Thank you sir.                                                                                     0810xxxxxxx

I suppose you are referring to an inflammed appendix. The symptoms have been treated before on this page and so I will just offer you a summary;

1) There is a throbbing pain in the right lower segment of the abdomen.

2) Sometimes, the pain begins first around the navel before shifting to that right lower corner.

3) The pain is often worse with walking or stooling and may extend to the thigh or the waist.

4) There may be a fever which can be of a low grade nature.

5) There is loss of appetite and of nausea.

6) Sometimes, the pain is so severe that you are unable to stand or walk erect. Rather, you will bend over forwards.

7) Sometimes, vomiting also occurs and it may be quite persistent.

Dear doctor, please a strange thing has been stopping me from bathing regularly with soap and sponge for some years now. Anytime I do so, my body itches me and I will begin to scratch it. Normally, this lasts for about 30 minutes or so before stopping. Is this a disease? And what can I do to stop it? Thank you.                                                                   0706xxxxxxx

What you are experiencing must be some kind of allergy or adverse reaction to either the sponge you are using or the soap, especially if it is the same kind of soap, or perhaps to certain elements contained in the bathing water. You do need therefore, to re-examine the source of the water supply you use. Then change your sponge or boil and sun it. And also change your soap. If you try to implement all these measures and they fail, you will have to see a dermatologist for examination and treatment.

Dear doctor, thanks for your column in SUNDAY PUNCH on the rising cases of madness on our roads. I also observe that in the last several weeks, you have been writing about various forms of mental health. Perhaps, the parlous state of the nation has something to do with that. Sometime in March, at the Ogba area of Lagos, one car rammed into another in heavy traffic. The offender who hit the car from behind told the other driver off and said it was the holdup that caused it. The driver of the car which was hit quietly got back in his car and when traffic moved a bit, he drove forward and reversed with speed into the vehicle behind breaking the headlamp. Then he did it again and shattered the grill. He was going for a third hit when the occupants of the car behind got out and ran. It was shocking to see.   0816xxxxxxx

Thank you very much as for that contribution. That is similar to a story I was told once also by a colleague who is very highly placed today which goes to show that such strange conduct is not necessarily dependent on social class.

Dear doctor, I have a penis condition of almost four years now. There is pale yellow urine, weak erection, extremely low libido, concurrent itching and pain at the tip and urethra. No ejaculation or with watery sperm. I don’t know if it is Peyronie’s disease or epispadias as your article noted in SUNDAY PUNCH of March 26. I need your help.                                                 0808xxxxxxx

Peyronie’s disease refers to an abnormal curvature of the penis which can be painful when erect. Epispadias is an abnormal opening of the urethra on the upper surface of the shaft of the penis. They are two different things. They are not even related. Pale yellow urine is the normal colour of urine that you should pass and there is nothing wrong with yours as far as that is concerned.

As for the true problems you mentioned, the weak erection, low libido and pain at the tip of the penis, it is important you see a urologist. That must be where to begin your search for a cure to your challenges. Good luck.

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