FAQs about Glaucoma and its medical and surgical management
What is Glaucoma?
Glaucoma is a group of eye diseases, which involve damage to the Optic Nerve. This may or may not be associated with raised pressure within the eye.
What is intraocular pressure(IOP)?
A certain amount of pressure is required within the eye to maintain its shape and size. A nourishing fluid called aqueous is constantly secreted in the eye. Accumulation of this aqueous generates pressure in the eye.
What happens in glaucoma?
When glaucoma is present the excess fluid cannot drain away properly due to a problem with the drainage system within the eye. The result of this means that as the fluid pressure in the eye increases this puts pressure on the Optic Nerve, so that is does not receive enough blood supply to work properly. The Optic Nerve sends messages to the brain and if damaged, the sight may become damaged as well.
Adult Glaucoma
How does glaucoma damage eye vision?
When the pressure is too high, damage occurs to the optic nerve. The optic nerve is made up of a bundle of nerve fibers which sends signals to the brain. Damage to the optic nerve can initially cause blind spots at the outer edges of the field of vision called peripheral or side vision. This is the main sign of glaucoma. As damage to the optic nerve gets worse, the visual field can shrink leading to tunnel vision or even loss of central vision affecting a patient’s ability to read. Fortunately, this occurs only in patients with very severe disease.
Who gets Glaucoma?
The genetic inheritance of glaucoma is still unclear. However, a family history of glaucoma has been found in up to 50% of patients with the most common type of glaucoma, known as primary open-angle glaucoma. One type of glaucoma occurs in people who have had a history of being hit in the eye (e.g. soccer ball). Not only can they get a rise in pressure initially after the injury, but they also may develop glaucoma years later. All of these things stress the importance of regular eye exams.
How do I know if I have glaucoma?
Unfortunately glaucoma is typically associated with painless and progressive loss of vision that may escape detection by the patient. This once again stresses the importance of a thorough eye history and examination, especially in patients with a family history of glaucoma. Only one type of glaucoma called angle-closure glaucoma is associated with a red, painful eye with blurred vision and even possibly nausea and vomiting. This is due to very high pressures resulting FROM a block in the drainage system of the eye. It is known as silent killer of the eye sight. thus a regular and thorough eye examination is the only way to detect it early.
How is glaucoma treated?
The primary goal of treatment is to preserve vision. The typical first line of treatment is eye drops which lower the intraocular pressure by helping fluid leave the eye or by reducing the amount of fluid produced in the eye. Some patients may need to take multiple different types of eye drops or even eye drops plus medications in pill form to effectively lower the pressure. In addition, there are laser treatments for both angle closure and open angle glaucoma. Laser treatment for angle closure glaucoma is usually performed to prevent an acute attack as described above; while laser treatment for open angle glaucoma is performed when medications are not effective enough or the patient has difficulty taking medications. Surgery, which involves making a drainage system for the fluid in the eye, is usually performed when medications and lasers are ineffective.
Who diagnoses and treats glaucoma?
Eye physicians and surgeons (ophthalmologists) are who have undergone specialized training in ORDER to treat eye diseases and to perform surgery. They are best qualified to diagnose glaucoma. Our eye specialist Dr. Mazhry takes special interest in medical and surgical management of glaucoma. He is an active member of Glaucoma society of Pakistan and has played a key role in glaucoma awareness at national level.
Acute Angle Closure Glaucoma
What is Angle Closure Glaucoma?
This is caused by a sudden and complete blockage to the outflow of fluid within the eye causing a sharp rise in the eye pressure. The eye pressure usually reaches exceedingly high levels and damage to the Optic Nerve can result if untreated. This condition is described as Acute Angle Closure Glaucoma which is an emergency condition.
Are there any individuals who are susceptible to this complaint?
Angle Closure Glaucoma occurs more often in individuals who have a narrow-angle between the iris (the coloured part of the eye) and the cornea (the clear front window of the eye), where a majority of the aqueous outflow occurs. Farsighted people (those who see better in the distance) are also more susceptible.
What are the Signs & Symptoms of an acute attack?
The eye may become very painful and due to the intensity of the pressure, nausea and vomiting may occur. It is possible to feel quite unwell.
- The eye may be red.
- The vision in the eye may decrease.
- The clear window at the front of the eye may become cloudy.
- The pupil (the black part of the eye) may be semi-dilated and fixed.
- Are there any Signs & Symptoms prior to a full-blown acute attack?
Yes, there can be. Acute Glaucoma attacks are not always full blown and can occur without any trigger event, but commonly occur in the evening because the pupil dilates in dim light. Seeing halos at night may precede an attack.
How is the pressure in the eye reduced?
A combination of medications will be used to bring the pressure under control as soon as possible. A drug to reduce the pressure in the eye may be given as the injection. The same drug may be given as a tablet form.
Will eye drops be necessary?
Numerous eye drops will be prescribed. One drop to constrict the pupil of the eye, one drop to reduce the production of the fluid in the eye, and one drop to reduce the redness and inflammation in the eye.
Is there any other treatment to keep the pressure under control?
Yes. As soon as the pressure has dropped to a safe level the eye doctor will perform a laser procedure called a Laser Iridotomy. This is where a laser beam is used to make a small opening in the iris to allow the fluid to flow more freely by creating a drainage hole. This is done to prevent future reoccurrence in the same eye.
Will the other eye require any treatment?
Laser treatment may also be performed on the other eye since it is common for both eyes to be the receptacle of the same condition. This is done as a preventative measure to prevent the same problem occurring in the other eye.
Congenital Glaucoma
What is congenital Glaucoma?
Primary congenital or infantile glaucoma is glaucoma that develops in the first few years of life and is thought to be the result of abnormal formation of anterior chamber angle (site of draining the eye fluid), causing obstruction of the fluid outflow and elevated eye pressures. – It may be associated with or without other eye and/or widespread abnormalities. – Juvenile glaucoma is glaucoma that develops after the 3rd year of life – In some children, secondary glaucoma may develop as a result of trauma or other eye diseases such as inflammatory, neoplastic, hamartomata’s, and metabolic diseases.
How frequent is primary congenital glaucoma?
1 out of 10,000 babies is affected. – It affects both eyes in 2/3rds of cases. It affects males twice as often as females and has no racial preference Does it affect high acuity, central vision? – Half of the patients will have visual acuity better than 20/50. But 2%-15% of the affected patients may become legally blind (vision less than 20/400 or restricted tunnel vision).
Is it inheritable? If I have it what are the chances my child will have it?
If there is no family history and a parent is affected, then there is a 5% chance the 1st child will be affected and a 5% that the second child will have the disease. If the first two children are affected then each subsequent child has 25% chance of being affected.
What do I usually see in my child?
The classic three symptoms of congenital glaucoma are:
tearing (epiphora),
bothered by light (photophobia) and
eyelid spasm (blepharospasm).
In addition, an enlarged eye(s) (buphthalmos) may be noted. –
The cornea may appear cloudy and swollen (corneal oedema).
Horizontal or concentric streaks may be seen. (Haab’s striae)
The pressure inside the eye is elevated usually in the 30 to 40 mmHg range. Normal is less than 16 mmHg in children. Only your eye doctor can determine that.
How is congenital glaucoma treated?
The primary treatment is surgical and much less medical (eye drops). – Procedures like goniotomy, trabeculectomy and trabeculectomy are performed to increase the outflow of the eye fluid and DROP the pressure inside the eye. – In cases not responding to the techniques described above, your doctor may implant a special device (valve or tube) to help with the outflow (draining) of eye fluid and lower the pressure. – If the above techniques fail your doctor may destroy the production site for the eye fluid (ciliary body) by laser treatment (cyclophotocoagulation) or application of a very cold probe (cryotherapy). – Medical treatment involves the application of eye drops and/or pills or liquid taken by mouth. – Medical therapy is used while waiting for the surgery, and it may be used afterwards to supplement.
What is the prognosis?
There is good prognosis in 80-90% of the patients if caught early. Some patients may have complications FROM this disease such as: amblyopia (developing a lazy eye), becoming nearsighted, developing retina detachment, astigmatism (irregular cornea) and lens dislocation.
Laser Treatment of Glaucoma
When is LPI(Laser peripheral iridotomy) indicated?
Laser peripheral iridotomy is generally recommended for patients with narrow angles, narrow-angle glaucoma, or acute angle closure glaucoma. When LPI is used in patients with narrow angles, it is considered to be a prophylactic procedure that prevents these patients FROM developing acute angle closure glaucoma, which they are at higher risk of developing. This is significant in that an acute attack of angle closure glaucoma usually presents with high eye pressures, pain, and loss of vision. When LPI is used in the treatment of patients who already have acute angle closure glaucoma, it is used to help lower the pressure as well as to prevent another attack of angle closure glaucoma.
What is LPI?
LPI attempts to “open” a “narrow” angle. Since the angle is the part of the eye that drains fluid FROM the eye, narrowing of the angle can put the eye at risk for an acute attack of angle closure glaucoma. During the LPI, a laser is used to make a small opening in the peripheral iris (the coloured part of the eye). This changes the fluid dynamics in the eye and “opens” the angle. If a patient already has acute angle closure glaucoma, the small opening that is made in the peripheral iris allows fluid to drain more normally and also lowers the eye pressure.
If I am having the LPI for preventing an acute attack of angle closure glaucoma, will this lower my eye pressure or improve my vision?
No, the LPI will not improve your vision or lower your eye pressure. It will only try to prevent your eye FROM developing an acute attack of angle closure glaucoma.
If I am having the LPI for treatment of an acute attack of angle closure glaucoma, will this lower my eye pressure and improve my vision?
In general, the LPI will help to lower your eye pressure which may then lead to an improvement of your vision. The amount of eye pressure lowering and the degree to which your vision will improve depends on the severity and duration of your acute attack of angle closure glaucoma. Sometimes, other medications or even glaucoma filtration surgery may be needed to ultimately control the eye pressure.
What should I expect if I have a laser iridotomy?
The procedure is an outpatient procedure that can usually be done in the eye doctor’s office. You are seated at a slit lamp with your forehead resting against a headpiece and your chin resting in a chin rest. After some eye drops are put in the eye in ORDER to numb the eye, a lens will be placed on your eye. This will prevent you FROM blinking and will also minimize your eye movements. The lens also helps to direct the laser light into your eye. The laser, which is attached to the slit lamp equipment, is then directed into the eye. The procedure usually takes a few minutes. Most people experience minimal discomfort during the procedure. After the laser, you may experience some irritation in the eye and some blurry vision, but this is largely resolved after a day or two. You will usually have your eye pressure checked one hour after the laser procedure. You are then usually seen the day after the laser procedure and/or the following week. The number and frequency of visits after the laser may vary and depend on the condition of your eye. Most people will need to be on an eye DROP four times a day for one week to help the eye heal FROM the laser.
What are some risks of laser surgery?
All laser procedures have some risks. Laser treatment is not done unless the benefits outweigh the risks. Risks include, but are not limited to, bleeding, inflammation, eye pressure elevations, and even vision loss. In general, serious risks are not common, however, you may want to discuss the benefits and risks with your doctor should you have any further questions.
Glaucoma Filtration surgery(Trabeculectomy)
When is trabeculectomy surgery indicated?
Trabeculectomy is generally recommended for patients with glaucoma that continues to progress despite the use of medications and/or laser treatments. In some cases, trabeculectomy surgery may be recommended prior to trying medical or laser treatment. These decisions vary depending on the type of glaucoma, the stage of glaucoma, as well as other factors. Sometimes this surgery can be combined with cataract surgery. What is done during trabeculectomy surgery?
A new drainage site is created to facilitate drainage of fluid from the eye. Instead of draining into the normal drainage site of the eye (the trabecular meshwork), the fluid is drained INTO a new space (a “bleb”) that is completely covered by the white outer covering (the conjunctiva) of the eye. This will lower the eye pressure. Since the surgery is usually performed near the top of the eye, the area of surgery usually cannot be seen afterwards because it is behind the upper eyelid.
Why do some trabeculectomy surgeries require the use of antimetabolites or medications that prevent scarring?
The main reason trabeculectomy surgery fails is that the drainage site can scar and therefore close up. Antimetabolites, or medications that prevent scarring, can be used to increase the success rate of trabeculectomy surgery in some patients. Since antimetabolites can increase the complication rate of surgery, it is generally reserved for patients that may be at increased risk for trabeculectomy failure. For example, patients who have failed previous trabeculectomy surgery, patients who are younger, patients who have had previous eye surgery in general, patients with uveitis, etc. The decision to use antimetabolites is determined by the surgeon. Not all patients who have trabeculectomy surgery need antimetabolites.
What are the antimetabolites that are used in trabeculectomy surgery?
5 Fluorouracil (5 FU) and Mitomycin C (MMC) are most commonly used. 5 FU can be given during the surgery and/or as injections around the eyeball after surgery. MMC is primarily used during surgery.
What should I expect if I have trabeculectomy surgery?
The procedure is done under local anesthesia in the operating room. After some eye drops are put in the eye and after the eye is numbed, your eye will be “prepped” or cleaned. A sterile drape will be put over your face and body and leave only your eye uncovered. This keeps the area of the operation clean and sterile. Your eye will be held open by a “lid speculum,” so you do not have to worry about blinking during the surgery. Some surgeons may also give you sedating medications through an IV (intravenous) line to keep you completely comfortable. After the surgery is over, a patch and shield will be placed over your eye. This will be removed the day after surgery on your first post-operative visit. You should expect to be seen quite frequently by your surgeon until the eye completely heals. For many people, this may be even for up to 2-3 months. During this time, you will be taking frequent and multiple eye drops. You may need either removal of sutures, a laser procedure to cut some sutures, injections of supplemental medications, or other office procedures to modulate and control the healing process. This will maximize the outcome of the surgery. The postoperative care will vary FROM patient to patient, and your doctor may not be able to predict what will need to be done after the surgery. This varies widely FROM person to person. You will also be restricted FROM strenuous activities during the healing process.
Will my glaucoma be cured with trabeculectomy surgery?
No. Any vision that is already lost prior to the surgery, in general, will not return. Trabeculectomy surgery only lowers your eye pressure. By lowering the eye pressure, the goal is to either stop or slow down your loss of vision. Sometimes this goal is not possible.
Can I stop my eye drops after the surgery?
You will definitely need eye drops for 2 or 3 months after the surgery. Some people do not have to take eye drops after that period. It is more likely that you will eventually need some glaucoma eye drops to keep your pressure under control. In some cases, people will be taking fewer eye drops than they were before the surgery. The need for eye drops long-term varies greatly and is determined by your type of glaucoma and the rate it is progressing.
What are some risks of Trabeculectomy surgery?
All eye surgery has some risks. Any operation is not done unless the benefits outweigh the risks. Risks include, but are not limited to, bleeding, infection, swelling, scarring, retinal detachment, a droopy eyelid, double vision, loss of vision or even loss of the eye. In general, many of these risks are not common, however, you may want to discuss the benefits and risks with your surgeon should you have any further questions. All surgery also has the possible need for another operation.
