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Symptoms of glaucoma can either be from build-up of pressure within the eye, or visual loss as a result of the high pressures.
Glaucoma can be broadly divided into two categories, "open" or "closed" angle, depending on the configuration of the drainage angle of the eye, where fluid (aqueous) is drained out of the eye. Depending on the rate of build-up of pressure, glaucoma can be further described to be "acute" (or sudden), or "chronic" (or gradual).
In most cases of open angle glaucoma and chronic closed angle glaucoma, the build-up of pressure is gradual, and without symptoms. Some patients may experience some glare and haloes around lights when the pressure is high. Additionally, there is a sub-group of glaucoma known as "normal tension glaucoma" in which the eye pressures are normal, but the optic nerve continues to be damaged. These patients will not have any symptoms from high pressures since the eye pressures will be in the normal range.
Visual loss from glaucoma usually starts from the peripheral field of vision, so blurring of vision due to involvement of central visual field is a late sign, when glaucoma is in its intermediate to advance stages.
Acute angle closure glaucoma, however, presents with dramatic symptoms of eye redness, pain, blurring of vision, together with headache, nausea, vomiting. This is due to the rapid and extreme build-up of eye pressure within the eye. This is an emergency and immediate medical attention should be sought.
Hence, most cases of glaucoma are without noticable symptoms in the early to intermediate stages. Patients who are at risk of developing glaucoma (such as those with a family history of glaucoma, who are moderately to severely short or long sighted, or have poorly controlled hypertension, diabetes, or have had previous injury or surgery to the eye) should get their eyes screened for glaucoma.
I am sorry to learn that your uncle has been diagnosed with glaucoma -- I hope his condition is in its early stages; I would strongly recommend that his family members (especially first degree relatives) get screened so that treatment be started, if necessary, to prevent irreversible visual loss.
Hope this helps!
The treatment options for glaucoma can be broadly divided into 3 categories -- medications, lasers, and surgeries. All these treatment options have the common aim of lowering eye pressures so that the optic nerve does not continue to be damaged, and vision can be preserved.
Medications are usually in the form of eyedrops. There are 5 classes of eyedrops (4 commonly used, 1 less common), which can be used either singly or in combination. Oral tablets/ liquids are reserved for selected cases in which the pressures are extremely high or rapid lowering of eye pressures are required, or when eyedrops no longer work. Medications lower the eye pressure by either reducing the amount of fluid (aqueous) produced, or increasing the rate of outflow of aqueous out of the eye.
Lasers can be used to treat both open and closed angle glaucoma. In open angle glaucoma, SLT (Selective Laser Trabeculoplasty) is a form of laser therapy that targets the drainage angle of the eye to increase the drainage of fluid (aqueous) out of the eye, resulting in lower pressures. LPI (Laser Peripheral Iridotomy) is another laser procedure that is the first line of treatment for angle closure glaucoma; it creates an alternative pathway within the eye for the flow of aqueous, which prevents the sudden dramatic rise in pressure that happens in acute angle closure. TCP (Trans-scleral Ciliary Photocoagulation) and its newer partner, MicroPulse TCP (mpTCP) can be used in more severe cases of both open and closed angle glaucoma, to destroy the cells producing aqueous within the eye so that eye pressures can be lowered.
Surgery is usually reserved for cases that do not respond to medications or lasers, or if medications cannot be tolerated due to unacceptable side effects. Trabeculectomy is a form of glaucoma surgery in which an alternative route of drainage of aqueous is created, such that fluid within the eye is diverted to a reservoir or bubble (bleb) outside the eye, resulting in lowering of pressures within the eye. Tube shunt surgery is another way in which aqueous can be diverted out of the eye, via a tube, to a bleb usually located under the upper eyelid. Newer, less invasive forms of glaucoma surgery, aptly named MIGS (Minimally Invasive Glaucoma Surgery) can be used to control mild to moderate glaucoma, and is usually done together with cataract surgery. These are usually stents or micro-tubes that are inserted into the drainage angle of the eye, to increase the flow of aqueous out of the eye, such that eye pressures are lowered, and glaucoma eyedrops can be reduced or stopped after the procedure.
In summary, there are numerous options for treatment of glaucoma -- medications, lasers, and surgeries, all with the goal of lowering eye pressures. Your uncle may require one or more types of treatment in order to control his glaucoma. It is important to remember that all forms of treatment cannot recover vision that has already been lost, but rather only preserve his remaining field of vision to prevent further visual loss and blindness.
Hope this helps!
Diabetes can affect the blood vessels that deliver oxygen to the eye, resulting in a lack of oxygen in the cells in the eye. When this happens, the eye responds by producing new blood vessels, with the hope of getting more oxygen delivered to its cells.
However, these new blood vessels grow hapzardly in different parts of the eye, including at the drainage angle, leading to obstruction of the drainage system that normally allows fluid (aqueous) to flow out of the eye.
As a result, aqueous fluid builds up in the eye, leading to (very) high eye pressures, damage of the optic nerve and loss of vision -- a condition known as neovascular ("new blood vessel") glaucoma, which is a serious form of secondary glaucoma, resulting from uncontrolled diabetes.
These abnormal new blood vessels are also very fragile and can easily bleed. The blood that is produced either in the front or back compartments of the eye can clog up the drainage system leading to high pressures, nerve damage and glaucoma.
These secondary forms of glaucoma can progress relatively quickly, leading to high pressures that are very difficult to treat, often requiring surgical or laser procedures in addition to eyedrops.
The good news is that this form of secondary glaucoma can be prevented if the blood glucose control is optimal. Furthermore, if detected early, the necessary laser procedures can be performed to prevent rise in pressure and blindness. However, as the condition can be relatively symptom-free until its late stages, do encourage your grandmother to keep to her eye reviews even though she may not have any eye symptoms.
Hope this helps!
The exact reason why myopia causes glaucoma is not known. One possible hypothesis is that when you have very high myopia, your eyeball becomes stretched and the tissue supporting the nerve in the eye is weaker so you are at more risk of nerve damage from high pressures (or even pressures in the "normal" range). Reduced blood flow to the optic nerve in highly myopic eyes could be another reason. However, these are all hypotheses which have yet to be proven.
What we do know from a study conducted in Singapore, is that glaucoma affects around 3 per cent of people over the age of 40 and the risk increases with age. In addtion, the risk of Chinese Singaporeans with myopia of getting glaucoma, as compared to those without myopia, are as follows:
In addition, Chinese with a family history of glaucoma were nearly 8 times more likely to develop it later in life.
Hence, if you have myopia or a family history of glaucoma (or both), do get screened for glaucoma. It is very important to remember that majority of cases of glaucoma are without symptoms in the early to intermediate stages of the disease. Blurring of vision, when experience, is often a late symptom and is irreversible.
Hope this helps!
I'm sorry to learn that your dry eye condition is causing you discomfort. Please resist the temptation to rub!
In my years of practice, I have seen some very bad consequences from vigourous eye-rubbing, including cataract and retinal detachment, which can be sight threatening!
Dry eyes is actually a relatively common condition, and majority of cases are (thankfully) mild. However I can empathize that the symptoms of grittiness, like having sand in the eye, tearing, and the fear of bright lights etc can be quite bothersome.
The good news is that most cases of dry eyes can be treated with lubricants. If you find that you need to use your lubricants more than 4 times a day I would generally recommend using a preservative-free type (that comes in disposable single-day use vials), so that the preservatives that are found in the bottled form (that can be used up to a month after opening) does not further irritate the surface of your eye.
Preservative-free lubricating eye drops are generally very safe for long term prolonged use.
Lubricating gels can also be used at night (and in the day) to provide more relief, although your vision may be temporarily clouded for a few minutes after applying the gel.
In addition to lubricants, I often advise my patients to perform regular lid cleansing. There is a row of oil glands behind our eye lashes, which function to secrete oil to lubricate the eyes and also prevent tears from evaporting too rapidly.
By cleaning your lids properly (twice a day), the opening of these glands can be unclogged so that oil can be secreted to keep the eyes moist.
The good news is that dry eyes does not cause glaucoma directly. However, more serious cases of dry eyes in which the transparent surface of the eye (cornea) is very rough or scarred up may require steroid eye drops, which can sometimes lead to pressure spikes in the eye.
These pressure spikes need to be detected and treated, to prevent progressive, irreversible damage to the nerve and loss of vision (=glaucoma).
Unfortunately there is seldom a complete "cure" for dry eyes. However, with a combination of lubricating drops and eye lid cleansing, most patients are able to keep their symptoms under control.
I hope you have sought treatment for your dry eyes, and are feeling better! Remember - do not rub your eyes! Feel better soon!
I am still experiencing some blurred vision in my right eye about 3 months after ReLEx Smile, and also starburst glares and halos. I am worried that this could be due to glaucoma. I would like to know if glaucoma is a known side effect of ReLEx® SMILE® please? Also, how is glaucoma diagnosed? I am particularly worried as I want to become a pilot.
I have been diagnosed with glaucoma for a few years now. It is now well-controlled with eyedrops. Am I suitable for TransPRK since it does not require the use of a suction device?
25 year old, been on a 30mg/week isotretinoin regime for about 6 months. Is isotretinoin likely to cause any retinal detachment in the long-term, or worsen thinning of the retina? Are there any additional risks if I have myopia of -9.00 or higher?