Glaucoma is a common condition and many of those who develop it aren’t even aware of what is going on:
There is actually more than one type of this eye disease but they share the common characteristic of causing optic nerve damage – usually, but not always, as a result of a build up of pressure in the eye.
This damage to the optic nerve is what causes problems with vision.
In most instances this disease will affect both eyes but this isn’t always the case.
It also tends to be more common in those who are over sixty and as we age the chances of developing it increases.
There is no actual full cure for the disease but it is possible to prevent further loss of vision in a lot of cases, or even prevent the progression to loss of vision.
Once damage has occurred to the retina though, there is nothing that can be done to rectify the condition.
There are five different types ; congenital , open angle , closed angle , secondary , and normal tension.
We will now examine each of these different types in a bit more detail.
Congenital is something that can affect children who are born with the condition. It is an eye defect that means there is a problem with fluid drainage – it is too slow.
Open angle is the most common of all the different types of glaucoma. It normally occurs slowly over time with the pressure in the eye gradually building up.
With closed angle there is a sudden increase in eye pressure and this can be very dangerous. This is why closed angle types will be treated as a medical emergency and action will need to be taken rapidly to prevent the loss of the eye.
The fact that it is secondary means that the build up of pressure in the eye has been caused by some other condition. There are many different conditions that could lead to secondary type including; diabetes, corticosteroids, eye tumours, an injury to the eye, cataracts that are advanced, or an inflammation of the eye.
Normal tension glaucoma is also sometimes referred to as low tension. It can progress in a similar way to open angle , or the symptoms can appear to come out of nowhere. Researchers are a bit unsure about how normal tension actually causes the damage, because unlike other types there is no increase of pressure to cause problems.
Glaucoma Signs and Symptoms
In the early stages there may be now symptoms to observe.
Things can progress unnoticed until one day the individual experiences a dramatic change to their vision; maybe they now have tunnel vision.
Glaucoma is the second leading cause of blindness in most parts of the world. It has been termed the ‘silent thief of sight’ because of the fact that it can progress unnoticed until it is too late.
This is why it is vital to have regular eye checks to ensure that you are not showing signs of this dsease’s progression.
If the condition is spotted early then treatment can be commenced thus preventing the loss of sight. The symptoms of open-angle type are a slow deterioration to peripheral vision which may eventually lead to tunnel vision.
With closed angle the symptoms are a lot easier to detect – in fact they are almost impossible to ignore. This is often an acute event and as previously mentioned it is a medical emergency. Those who have closed angle are likely to experience –
– A sudden onset of problems to vision; things may be worse in a low light.
– Intense eye pain
– Images appear blurry
– The eye will usually look red
– There may be the appearance of halos around lights
– There is often nausea and vomitin
Anyone who experiences these symptoms should get help right away.
Some of these symptoms can be caused by less serious eye problems but it is always better to be safe than sorry.
In order to determine if you have developed this eye problem there is likely to be a number of different tests carried out; this could include –
– A detailed history of your health and the exact details of any symptomsyou have been experiencing. It is important to be as clear as possible about the symptoms you have been experiencing. It may help if you right these down before you visit the doctor. You will want to describe what the symptoms are like, when you first began noticing them, and how long they last (do you experience the symptoms all the time?). You will also want to describe any other symptoms or changes you have noticed.
– You are likely to have your peripheral vision checked using a visual field test. This usually involves a special a machine which can be operated automatically or controlled by a technician. There are also computerised versions of this test that can be found online for self-testing.
– The doctor may use a special instrument to look through your pupil to the back of the eye in order to look for any possible optic nerve damage.
– Another test involves numbing your eye with special drops and then measuring the pressure inside the eye.
– The pachymetry exam also involves numbing your eye using drops. The aim here is to determine the thickness of your cornea. This exam allows the doctor to determine if your high eye pressure reading is due to a thick cornea – if it is then you might not have glaucoma.
As well as the above tests the doctor might also use special techniques to determine if you have open angle or closed angle types.
Before going onto the causes it might be helpful to consider the anatomy of the eye first of all; that way we will have a much better understanding of how the condition affects us.
The purpose of our eyes is to pick up light and reflect this to the back where the retina is situated; it is sort of life a cinema projector sending an image to a screen. The eye is a small but very complex structure but basically what happens is that –
1. Light enters the cornea; this is the front part of the eye.
2. It then goes through the pupil in the iris; this is the part of the eye that gives us our eye colour. The purpose of the iris is to control the amount of light that can pass through the eye by contracting and dilating the pupil.
3. The lens is at the back of the iris and this is where the light goes next. The lens is clear and works in a similar way to a lens on a camera. It focuses the light so as to continue its journey to the back of the eye.
4. Most of the eye is made up of vitreous. This is a transparent substance that helps maintain the shape of the eye. It is thicker than water and this means that it is able to keep the eye intact.
5. After the light passes through the vitreous part of the eye it hits the retina. The purpose of the retina is to turn the light into signals that are then sent to the brain via the optic nerve.
There is still debate as to the exact causes of glaucoma.
However, it is agreed that it is usually the build up of pressure in the eye that damages the retina; this is called intraocular pressure. This build up of pressure is due to aqueous humor fluid that has now increased more than normal. Under normal conditions this fluid, which is produced at the front of the eye, is kept in balance through a drainage system. This drainage system can be found right at the angle where your cornea and iris meet. If anything interferes with this drainage system it means that the fluid accumulates above normal limits and it is this that causes the problems.
With open angle glaucoma the drainage system is only partially blocked, and this means that the fluid drains more slowly than would normally be expected. With closed angle glaucoma the drainage system is blocked off or narrowed and this means that the pressure can build up in a very short amount of time. In most instances closed angle glaucoma will be an acute event, but it could possible occur over a longer period of time; this is referred to as chronic angle closure glaucoma. A lot of people who develop this closed angle glaucoma may have always had a narrow drainage angle and so are more prone to this type of event.
Low tension glaucoma is a bit of a mystery. This is a fairly common form of glaucoma but in with this type there is no rising pressure within the humor fluid to damage the retina. There is a theory that the reason it happens is due to individual’s having abnormally sensitive retinas that can become damaged more easily. It could also be that this glaucoma is due to another process such as the failure of an adequate blood supply to reach the retina; perhaps due to the build up of plaque (atherosclerosis) that can occur elsewhere in the body. There is still more research being carried out but it is likely to take a lot more work before we fully understand low tension glaucoma.
Glaucoma Risk Factors
It is the case that some people are more likely to develop these disease than others. Here are the most common risk factors that have thus far been identified:
1. People of African or Afro-Caribbean origin are more at risk of developing open angle glaucoma. They are also more likely to develop the problem at a younger age than the average
2. Many individuals can start experience problems once they are over forty years old.
3. Those of Asian origin seem to be more prone to developing acute closed angle glaucoma.
4. Age is seen as an important risk factor with the chance of developing glaucoma increasing as we get older. Most people with open angle glaucoma will start developing problems when they are older than sixty years of age.
5. Those with a family history of glaucoma have an increased risk of developing the condition. If a close relative such as a parent or sibling has the developed glaucoma then this increases the likelihood of it arising.
6. There are certain medical conditions such as diabetes that can greatly increase the chances of developing glaucoma. Hyperthyroidism also increases your risk of getting glaucoma.
7. People who are short-sighted tend to be more likely to develop the condition.
8. People who use corticosteroids over a long period seem to be more likely to develop glaucoma.
9. Anyone with ocular hypertension (high pressure in the eye) will have an increased risk of developing glaucoma. It should be noted though, that just because you have high pressure in the eye it doesn’t necessarily mean that you will develop glaucoma.
10. If you have had an eye injury or eye infection then this could contribute to the arrival of glaucoma.
Treatment and Management
There are quite a number of different treatment options for dealing with this eye disease. It can’t be completely cured, but there is usually a lot that can be done to prevent further deterioration. If there has already been some damage to the retina then there is very little that can be done about this. The option that is chosen will depend on the type of glaucoma and how advanced it has progressed. Most treatments will be either aimed at reducing the production of aqueous fluid or improving the functioning of the drainage system.
Some of the treatments that are likely to be recommended will include:
Eye drops This tends to be the first treatment option offered; especially with early stage open angle glaucoma. If you are given eye drops by your doctor it is crucial that you take them as directed; failure to do so will mean that the treatment won’t be as effective. There are quite a number of different eye drops that can be prescribed for this condition including –
• Carbonic anhydrase inhibitors work by reducing the production of aqueous fluid. There can be some other side-effects of this medicine including; the need to pass urine more frequently and a tingling sensation in parts of the body. There are a number of different drugs like this with the two most common being brinzolamide and dorzolamide.
• Alpha-agonists are another type of drug that works by reducing the production of acqueous fluid. Some people can have an allergic response to this drug and there are also possible side effects like swollen eyes, itchiness, dizziness, and fatigue. The two most common forms of this eye drops are brimonidine and apraclonidine.
• Beta blockers also have the ability to slow down the production of aqueous fluid. Individual with certain conditions like respiratory problems or diabetes might not be able to take this type of medication. The possible side effects with beta blockers includes low blood pressure, hair loss, depression, bradycardia (slow pulse), depression, impotence, depression, memory loss, and tiredness. The most common type of beta blockers used as eye drops include betaxolol, timolol, and metipranolol.
• Epinephrine eye drops work by increasing the outflow of the aqueous fluid so that drainage is improved. This type of medication could possibly cause anxiety, high blood pressure, headaches, red eyes, and palpitations.
• Latanoprost and bimatoprost are prostaglandin-like compounds that work by increasing the flow of aqueous fluid. This type of drug can cause visual problems and a possible stinging sensation in the eye.
• Pilocarpine and carbachol are cholinergic agents that also make the drainage system in the eye perform better. This drug can sometimes cause visual problems as well as digestive complaints. Some people can have an allergic response to this type of eye drop.
It may take a few attempts before your doctor finds the right selection of eye drops to treat the glaucoma. Every drug has side effects, but this does not mean that you are going to experience all of these negative problems. If you do appear to be having an adverse reaction then you need to speak to your doctor about this. The main thing is that you take these eye drops exactly as prescribed.
If you have never dealt with eye drops previously you may be a bit confused about what to do. Here are some basic instructions for putting these drops into your eyes:
– Make sure your hands are clean.
– Read the instructions on the eye drops carefully; some require that you shake the bottle before you apply, but not all will want you to do this.
– Open the eye drops.
– Tilt your head back.
– Use the hand that isn’t holding the eye drops to gently pull down your eyelid.
– Roll your eyes upwards.
– Squeeze the eye drops to administer the fluid into the base of your eye; only administer the exact number of drops stated.
– Wipe off any excess fluid, and close your eye for a minute or two to encourage absorption.
In most instances the eye drops will be enough to reduce the pressure in the eye, but not always. Your doctor might decide that it would be more effective to take oral medication. If this is the case you will need to follow the instructions in regards to dosage and times of administration. These oral medications work in more or less the same way as the eye drops, but the side-effects can sometimes be more noticeable. It is usually advised that you take these oral medications with food because this can help reduce the possible of side-effects; always check the instructions first.
As well as the eye drops and oral medication mentioned above there are also many other compounds that are being investigated. It is likely that over the next few years there will be new ways to treat the condition, and hopefully these will be even more effective and not involve as many possible side-effects. At the moment though, there is no real wonder drug for treating glaucoma.
Some people don’t do very well with eye drops or oral medications and in these instances it may be necessary for surgery to be performed in order to treat the condition. Even if you have the surgery it still could mean that you will need to take eye drops or other medications following it. Like all operations there are potential risk as well as benefits associated with surgery for glaucoma. There are a number of different surgical procedures that could be advised including –
Drainage Implant Surgery
Drainage implant surgery is most often used to treat those with congenital or secondary glaucoma. This type of procedure does not usually require a stay in hospital and can be performed as an outpatient. It is a relatively straightforward type of treatment that involves inserting a small silicon tube into the eye; as the name suggests this will hopefully mean that drainage from the eye is much improved. Following the procedure the individual will be expected to wear an eye patch for a day or two; it will also be necessary to take eye drops for a few weeks as well.
Laser Surgery for Glaucoma
In recent years laser treatment has become a very popular method for dealing with glaucoma; especially in those instances where medication has failed to control the situation. This procedure is also known as a trabeculoplasty and it is used for the treatment of open angle glaucoma. The treatment involves using high intensity laser beams to open back up those drainage canals that have become narrow; this will then mean that the aqueous fluid will once again be able to flow more normally.
The actual treatment is fairly straightforward and only takes about twenty minutes to perform. You will be given special eye drops that will numb the eye first of all and then the laser will be directed into the eye. After the procedure you shouldn’t feel too much discomfort and you will probably be able to go about your daily activities as normal right away. You will need to return again for another appointment to check if the treatment has indeed managed to bring down the pressure in your eye. It should also be noted that the positive effects of laser surgery for glaucoma are unlikely to last for the rest of your life and you may need to repeat it again; hopefully not for a long time though.
Filtering surgery is usually only performed when everything else has failed. It is more invasive than the other types of procedure because it involves actually cutting into your sclera in order to remove some of the drainage canal tubular; this should then mean that the fluid can move more freely. It is possible to have this procedure down as an out-patient, but a lot of people end up staying at least overnight in hospital. The eye will be first numbed using an injection or eye drops.
This is a delicate operation that involves special tools and a microscope so that he surgeon can see what he is doing. The fact that this procedure involves making an incision in the eye means that there is more potential for complications; including the risk of infections. Those performing the procedure are well aware of the risk and will do all they can to prevent them from occurring; they are usually successful in this.
The Treatment and Management of Acute Closed Angle Type
As mentioned earlier acute closed angle is considered a medical emergency; if not dealt with quickly it will likely lead to the loss of the eye. With closed angle glaucoma the drainage system is either completely blocked or severely narrowed. The pressure inside the eye rises and if it becomes high enough will start to cause irreparable damage to the retina. The goal then of the emergency treatment will be to bring the eye pressure down as fast as possible. The first action that doctors may try is using medications to bring the pressure down. An iridotomy may be performed and this involves using a laser to put a whole in the iris; this will increase the flow of aqueous fluid.
How to Live With Glaucoma
If you have this eye condition you may have to make a few changes to your lifestyle.
Exercise is good for our health but if we have glaucoma we need to be careful that we don’t exercise too vigorously as this might increase the pressure in the eye.
It is strongly advised that you speak with your medical team in regards to exercising and how to perform it safely.
Another lifestyle change that may be requires is that you avoid drinking too much fluid all in one sitting as this could increase the pressure in your eye; drink little but often – again this will be something you will want to discuss with your health care professional.
There is a lot of debate about the usefulness of alternative treatments for dealing with eye pressure disease.
Herbal remedies in particular tend to be viewed suspiciously by doctors, and there is not enough evidence that they provide any benefit – they could even make things worse.
Anything that can help you relieve stress can be good though so mediation and other relaxation techniques might be useful.
Those planning on doing yoga should check with their doctor first of all because some positions can increase pressure in the eye for certain types of glaucoma.
One thing that can be very important for people with this eye disease is that they get plenty of support.
This can be a very debilitating condition and individuals can be very anxious and depressed about having to deal with the loss of sight.
The fact that there are so many people who need to deal with glaucoma means that there should be no problem finding support.
As well as groups and information services there are also plenty of online resources which can be a great help.
The ability to discuss problems with people who understand can be a great way to ease concerns.
Finding out more about the condition and possible treatments can be very empowering and these days most patients prefer to play an active role in their own treatment.
Technology and Glaucoma
We are lucky enough to live in an age where there is plenty of technology around to make life easier.
There are many devices that may help those that have lost visual ability due to this eye problem; this technology means that they can continue to enjoy books and even use the computer.
Almost every book is now available in an audio format, and many classic novels can be found free of charge.
Another impressive development is text to speech technology which turns any text on the computer into spoke language.
If glaucomatous eye disease is left untreated it can lead to big problems.
I cannot be cured completely but it is possible to slow down the progression.
It is usual for the disease to progress through three stages which include:
1. Problems with peripheral vision
2. Tunnel vision
3. Eventually – complete blindness.
If nothing is done to stop the progression then the loss of sight is likely.
Acute closed angle type needs to be dealt with right away or there is a huge risk that the eye could be lost.
Once damage has occurred to the retina it cannot be repaired.
All that can be done is to prevent further damage!