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How should I use my glaucoma eyedrops?

If eyedrops have been prescribed for treating your glaucoma, you need to use them properly and as instructed by your eye care professional. Proper use of your glaucoma medication can improve the medicine's effectiveness and reduce your risk of side effects.

To properly apply your eyedrops, follow these steps:

• First, wash your hands.

• Hold the bottle upside down.

• Tilt your head back.

• Hold the bottle in one hand and place it as close as possible to the eye.

• With the other hand, pull down your lower eyelid. This forms a pocket.

• Place the prescribed number of drops into the lower eyelid pocket. If you are using more than one eyedrop, be sure to wait at least five minutes before applying the second eyedrop.

• Close your eye OR press the lower lid lightly with your finger for at least one minute. Either of these steps keeps the drops in the eye and helps prevent the drops from draining into the

tear duct, which can increase your risk of side effects.

Glaucoma could interfere with sleep or cause depression

Glaucoma, by way of disrupting circadian rhythms, could interfere with sleep or cause depression, a new study suggests.

"We propose that glaucoma may be the primary ocular disease that directly compromises photic input to the circadian time-keeping system because of inherent ganglion cell death," according to lead study author Girardin Jean-Louis, Ph.D., clinical assistant professor, Department of Ophthalmology, SUNY Downstate Medical Center, Brooklyn, N.Y. The work was published in the January 2008 issue of the Journal of Circadian Rhythms.

While the study did not perform a randomized trial, it hypothesized that ocular diseases--and most especially glaucoma--can disturb sleep by reducing light transmission. This reduction, in addition to inadequate exposure to the light-dark cycle, can cause circadian misalignment and sleep disturbances.

How disease could affect sleep

Dr. Jean-Louis noted that ophthalmic diseases that could affect "photopic input to the circadian system" include cataract, diabetic retinopathy, macular degeneration, retinitis pigmentosa, optic nerve atrophy, and glaucoma. "

Plausibly, cataract, defined as opacity of the crystalline lens of the eye, does not diminish light input significantly unless the disease is far advanced," Dr. Jean-Louis wrote. Meanwhile, diabetic retinal diseases vary in their severity, consequently affecting light input to various degrees. Other diseases also have a varying impact on light levels.

Glaucoma would have a twofold impact, Dr. Jean-Louis wrote, including, "1) a direct impact through degeneration of retinal ganglion cells and/or ocular ischemia and reperfusion damage and 2) an indirect impact through social isolation due to blindness."

He continued, "Glaucoma is an ocular degenerative disease that affects ganglion cells, eventually causing optic nerve dysfunction by way of axonal loss. Reduced axonal stimulation to the central visual pathways likely diminishes light input to the circadian system. This is supported by recent evidence that melanopsin, which is found in retinal ganglion cells,is a major photopigment involved in circadian entrainment."

So while a disease like retinitis pigmentosa would cause progressive degeneration of rods, glaucoma affects ganglion cells, which may have more of a direct link to maintaining normal circadian rhythm.

"Light-regulated functions--entrainment of the circadian pacemaker, suppression of activity and melatonin rhythms, and modulation of the papillary reflex--involve special signal transduction mechanisms of intrinsically photosensitive retinal ganglion cells," Dr. Jean-Louis wrote.

"These cells are believed to harbor melanopsin, the primary photopigment in the synchronization of circadian rhythms." Already, research analyzing patients aged 12 to 20 years old from the Missouri School for the Blind found that patients with optic diseases showed greater circadian dysfunction, such as more napping during daytime hours and variable time of awakening compared to those without disease.

Who is affected

If Dr. Jean-Louis's hypothesis is correct, glaucoma patients--and in particular African-Americans--could be at higher risk for depression and sleep disturbances. "Glaucoma, for instance, is more prevalent among African-Americans, and ambient light data have shown reduced illumination among AfricanAmerican men and women, compared to their Caucasian counterparts," Dr. Jean-Louis noted. Dr. Jean-Louis's hypothesis also offers further compelling reasons for glaucoma patients to take their eye drops. Not only would they potentially be preserving vision, they would also help preserve sleep and good moods.

Meanwhile, Mark Packer, M.D., clinical associate professor, ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, said it makes sense that glaucoma could affect circadian rhythm. "There is a subcortical connection between the retina and melatonin, which establishes circadian rhythm," Dr. Packer said. "There are subcortical pathways by which I mean neural pathways from the eye that do not come to the visual cortex. These are pathways that go from the eye and eventually get to the pineal gland, where melatonin release is mediated. So you could imagine that someone who has glaucoma--if you've lost half of your neurons, the input to those areas that mediate melatonin release may be reduced as well."

Melatonin, meanwhile, acts on the release of cortisol, "which is kind of what gets you up in the morning," Dr. Packer said. Cortisol "is the mediator of your sympathetic response, it's what is released when you get palpitations, sweaty palms, blood pressure and arousal levels." All this could get messed up "in people who have reduced input from eyes due to atrophy of the nerve fiber layer," Dr. Packer said. He said he hasn't noticed that glaucoma patients have disturbed sleep, but then again, he said his clinic up until now hasn't asked that question. The study's hypothesis was interesting enough, however, for Dr. Packer to say he might start asking this question to patients. Editors' note: Dr. Jean-Louis has no financial interests related to this study. Dr. Packer has no financial interests related to his comments. Contact Information Jean-Louis: gjean-louis@downstate.edu Packer: 541-687-2110, mpacker@finemd.com

Other types of glaucoma

If there is inflammation in the eye (anterior uveitis), adhesions may develop between the lens and iris (posterior synechiae). These adhesions will block the flow of aqueous between the posterior and anterior chambers and result in forward ballooning of the iris and a rise in the IOP. Adhesions may also develop between the iris and cornea (peripheral anterior synechiae), covering up the trabecular drainage meshwork.

Inflammatory cells may also block the meshwork. Topical steroids may cause a gradual asymptomatic rise in IOP that can lead to blindness. (Patients taking topical steroids over a long period should always be under ophthalmological supervision.) The growth of new vessels on the iris (rubeosis) occurs both in diabetic patients and after occlusion of the central retinal vein resulting from retinal ischaemia. These vessels also block the trabecular meshwork causing rubeotic glaucoma, which is extremely difficult to treat.

The trabecular meshwork itself may have developed abnormally (congenital glaucoma) or been damaged by trauma to the eye. Patients who have had eye injuries have a higher chance than normal of developing glaucoma later in life. If there is a bleed in the eye after trauma, the red cells may also block the trabecular meshwork.

Surgical treatment for glaucoma

Surgery was traditionally used only when treatment had failed to halt the progress of glaucoma, but there is some evidence that earlier surgical intervention is beneficial for selected patients.

Iridectomy

Peripheral iridectomy is performed in cases of angle closure glaucoma, both in the affected eye and prophylactically in the other eye. Most of these cases can be treated with the Nd-YAG laser. Surgery is reserved for difficult or refractory cases.

Drainage surgery

When it is not possible to achieve the target IOP with medical (or laser) therapy in glaucoma, then the next line of management is surgical. The most effective glaucoma filtration procedure is trabeculectomy. In this procedure a guarded channel is created, which allows aqueous to flow from the anterior chamber inside the eye into the sub-Tenon's and subconjunctival space (bypassing the blocked trabecular meshwork). A drainage "bleb" (aqueous under the conjunctiva and Tenon's capsule) can often be seen under the upper lid. Conjunctivitis in a patient with a drainage bleb should always be treated promptly, as there is an increased risk of the infection entering the eye (endophthalmitis).

Possible complications

The main cause of surgical failure is postoperative scarring of the drainage channel and drainage bleb. Scarring can be reduced by using adjuvant antiscarring therapy. Various antiscarring agents are used, including drugs used in anticancer therapy. These are delivered by short applications during surgery to the drainage bed on a sponge or by postoperative injections. The most commonly used drugs are 5-fluorouracil and mitomycin-c.

Glaucoma filtration procedures do carry some risk and the patient should be advised of the risk of postoperative cataract and hypotony (low pressure) and the possibility of a reduction in postoperative best corrected visual acuity.

Although trabeculectomy remains the gold standard glaucoma filtration procedure, several alternative filtration operations also exist. Non-penetrating deep sclerectomy and viscocanalostomy have good safety profiles but have tended to produce less dramatic reductions in IOP in all published trials.

For certain patients with refractory glaucoma, a tube drainage device may be considered. A drainage tube is inserted, connecting the anterior chamber of the eye with a reservoir in the posterior orbit. This has a good chance of controlling IOP, but also has moderately high risk of serious complications.

Laser treatment for angle closure glaucoma

Laser trabeculoplasty
Argon or diode laser "burns" are applied to the trabecular meshwork. How this treatment works is uncertain. It was thought to contract one part of the meshwork, so stretching and opening up adjacent areas, but a more recent hypothesis is that it rejuvenates the cells in the trabecular meshwork. This treatment is used only in the types of glaucoma where the drainage angle is open. Its effect is relatively short term, so this treatment is mainly used for more elderly patients.

Laser iridotomy

Peripheral laser iridotomy (PI) can be performed in cases of angle closure glaucoma with the Nd-YAG laser, which (unlike argon or diode lasers) actually cuts holes in tissue rather than just burning. This procedure can be performed without incising the eye.

Laser iridoplasty

Argon laser iridoplasty is a useful procedure in some forms of angle closure glaucoma. A ring of laser burns is applied to the peripheral iris, causing contraction of tissue. This pulls the peripheral iris away from the drainage angle and helps to reduce angle occlusion.

Laser ciliary body ablation

Lasers can be used to burn the circular ciliary body that produces the aqueous humour. At the correct wavelength the laser radiation passes through the white sclera and is only absorbed by the pigmented ciliary body (transcleral ciliary body cycloablation). This treatment is now commonly performed with a diode laser and usually has to be repeated to maintain lowering of IOP. Most patients undergoing laser ciliary body ablation need to continue medical therapy. Laser destruction of the ciliary body usually is used only in advanced refractory glaucomas or where other surgical options are limited.

Symptoms and clinical signs of glaucoma

A patient with primary open angle glaucoma (also known as chronic open angle glaucoma) may not notice any symptoms until severe visual damage has occurred. This is because the rise in intraocular pressure and consequent damage occurs so slowly that the patient has time to compensate. In contrast, the clinical presentation of acute angle closure glaucoma is well known, as the intraocular pressure rises rapidly and results in a red, painful eye with disturbance of vision.

Raised intraocular pressure

Most patients with raised intraocular pressure (IOP) are unaware that they have a problem. Raised IOP is detected most commonly through screening as part of a routine eye test by an optometrist. The IOP is determined by the balance between aqueous production inside the eye and aqueous drainage out of the eye through the trabecular meshwork. Each normal eye makes about 2
l of aqueous a minute¡ªthat is, about 70 litres during the course of a lifetime. In a British Caucasian population, 95% of people have an IOP between 10 and 21 mm Hg, but IOP can drop as low as 0 mm Hg in hypotony and can exceed 70 mm Hg in some glaucomas.

The rate at which raised IOP causes optic nerve damage depends on many factors, including the level of IOP and whether glaucomatous damage is early or advanced. In general, raised IOPs in the 20-30 mm Hg range usually cause damage over several years, but very high IOPs in the 40-50mm Hg range can cause rapid visual loss and also precipitate retinovascular occlusion.

Haloes around lights and a cloudy cornea

The cornea is kept transparent by the continuous removal of fluid by the endothelial cells. If the pressure rises slowly, this process takes longer to fail. When the pressure rises quickly (acute closed angle glaucoma) the cornea becomes waterlogged, causing a fall in visual acuity and creating haloes around lights (like looking at a light through frosted glass).

Pain

If the rise in pressure is slow, pain is not a feature of glaucoma until the pressure is extremely high. Pain is not characteristically a feature of primary open angle glaucoma.

Visual field loss

Pressure on the nerve fibres and chronic ischaemia at the optic nerve head cause damage to the retinal nerve fibres and usually results in characteristic patterns of field loss (arcuate scotoma).

However, this spares central vision initially, and the patient does not notice the defect. Sophisticated visual field testing techniques are required to detect early visual field defects. The terminal stage of glaucomatous field loss is a severely contracted field, because only a few fibres from the more richly innervated macula area survive. Even at this stage (tunnel vision) the vision may still be 6/6.

Optic disc changes

The optic disc marks the exit point of the retinal nerve fibres from the eye. With a sustained rise in IOP the nerve fibres atrophy, leaving the characteristic sign of chronic glaucoma¡ªthe cupped, pale optic disc.

Venous occlusion

Raised IOP can impede blood flow in the low pressure venous system, increasing the risk of retinal venous occlusion.

Enlargement of the eye

In adults no significant enlargement of the eye is possible because growth has ceased. In a young child there may be enlargement of the eye (buphthalmos or ¡°ox-eye¡±). This tends to occur with raised IOP in children under the age of three years. These children may also be photophobic and have watering eyes and cloudy corneas.

Enlarged watering eyes

with cloudycorneas in a child with glaucoma

Compliance with glaucoma medications

Compliance with glaucoma medications, as with medications for any type of chronic diseases, is a major risk factor for progression. In the study by Kass et al. (12) using an eyedrop medication monitor, compliance with pilocarpine was found to be very poor. Fifteen percent of patients administered less than one-half of the prescribed doses.

Twenty-five percent of patients missed at least 1 day per month. When interviewed, however, patients reported taking an average of 97% of prescribed doses. In general, compliance with medications decreases with the frequency of dosing and the number of medications. However, even with newer medical therapies with less frequent dosing, compliance continues to be very poor (13). This is further exacerbated by the fact that glaucoma is an asymptomatic disease until the very late stages, and therapy does not result in any subjective improvement in their condition. Other major reasons for noncompliance include medication side effects (both local and systemic) and difficulty administering the medication.

In a patient where target IOP cannot be achieved consistently due to noncompliance, surgery must be seriously considered but only after patient education has been tried. The majority of the reasons sited by patients for noncompliance is not related to social or environmental factors and may be amenable to patient education or modification of medications (13). These include regimen factors (e.g., cost, complexity and side effects), patient factors (lack of knowledge/skill, forgetfulness, lack of motivation, and complexities created by co-morbidities), and medical provider factors (e.g., dissatisfaction with care and lack of communication).

Some situational compliance factors may be difficult to remedy. Patients who live in parts of the world where drops are not available or are prohibitively expensive, or live alone and have difficulty in administering the drops for physical reasons require earlier glaucoma surgery in order to achieve target pressures (14,15). However, caution must be exercised since good compliance with medications is required postoperatively in order to reduce potential surgical complications and enhance the chance of successful surgery.

Indications for Glaucoma surgery:A Review of Recent Clinical Trials

Glaucoma surgery is indicated when target pressures are not achieved, or when neural tissue or visual function is progressively lost despite maximally tolerated medical and laser therapies.

Target pressure is generally accepted to be the pressure at which progression of glaucomatous

optic neuropathy is unlikely to continue. It is an attempt to prevent progression in a prospective manner. Target pressures need to be re-evaluated periodically and re-set at a

lower level if progression continues.

At the present time, the success of target pressure estimates can only be determined in a retrospective manner after many years of treatment.Recent multi-center, randomized controlled trials have demonstrated the efficacy of lowering intraocular pressure (IOP) in reducing both the risk of developing glaucoma and progression of the disease, and provide some help in choosing the initial target pressure.

Studies clearly show the benefit of IOP reduction in the management of glaucoma and selected patients with ocular hypertension, and help us to set initial target pressures. Lower pressures
12–15 mmHg clearly result in a lower risk of progression,but even reducing IOP by 20% has a protective effect. Advanced disease requires lower pressure when compared with early disease in order to halt or minimize the risk of of progression. It is for this latter group that surgery should be considered sooner than later.

The risk of progression posed by IOP must always be balanced with the risks of treatment. This is especially true when surgery is being considered. There is even some 4 Sit and Trope discussion as to whether patients are being over-treated in the zeal to reach the target pressure, particularly with early glaucoma. It is instructive to consider that the OHTS

found that 90% of untreated ocular hypertensives did not progress over 5 years.

Clearly, however, patients with advanced disease require aggressive therapy. However,not all glaucoma patients require an IOP of 12–14 mmHg. For example, an 85-year-old with a 0.75 cup-to-disc ratio and an IOP of 18 mmHg will likely not go blind from progressive optic neuropathy despite this IOP level. However a 55-year-old with a 0.9 cup-to-disc ratio and the same IOP level with a life expectancy of at least another 20 years is at greater risk of blindness if IOP is not dropped into the low teens. Spaeth has suggested that the goal of treatment is not to prevent disease progression, but to prevent patients from becoming symptomatic or from becoming more symptomatic

Glaucoma, Alzheimer‘s Disease Linked

Scientists today announced that Alzheimer's disease and glaucoma share a risky protein called amyloid beta.

Targeting amyloid beta with Alzheimer's drugs may help treat glaucoma, according to the researchers, who work in the U.K. and elsewhere in Europe.

Amyloid beta is a key ingredient of the brain plaque seen in Alzheimer's patients. Amyloid beta is also associated with glaucoma, new research shows.

The findings come from M. Francesca Cordeiro, MRCP, PhD, and colleagues.

Cordeiro works at the Glaucoma and Retinal Degeneration Research Group at University College London's Institute of Ophthalmology. Her MRCP degree means she's a doctor who's a member of the U.K.'s Royal College of Physicians.

Glaucoma is a leading cause of blindness. Cordeiro's team studied glaucoma in rats, not people.

Due to glaucoma, the rats lost nerve cells in their eyes that transfer visual information from the eye to the brain, the researchers report. As that happened, amyloid beta built up in the area where those nerve cells had been.

To try to thwart that process, the scientists targeted amyloid beta with various types of drugs. That strategy reduced the number of nerve cells in the rats' eyes that died. The researchers got the best results when they gave the rats three types of drugs at once, instead of just one drug.

"We have shown that amyloid beta could be a particularly suitable target for therapeutic intervention in the eye" to help protect those nerve cells that glaucoma ravages, write Cordeiro and colleagues. Further research is needed to see if that approach will work in people.

In a news release, Cordeiro notes that "this doesn't mean that everyone with Alzheimer's will develop glaucoma or vice versa."

The findings appear in this week's early online edition of the journal Proceedings of the National Academy of Sciences.

New Glaucoma Treatments

Sixty-seven-million people around the world cannot see because they suffer from the disease glaucoma.

The disease prevents the clear fluid in the eye from flowing normally. This causes increased fluid pressure inside the eye. The increased pressure can damage the optic nerve that carries images from the eye to the brain.

The most common kind of glaucoma mainly affects people over forty years old.People with family members who have the disease are more likely to develop glaucoma. Black people also are at higher risk for the disease. Others at high risk include people suffering from diabetes or high blood pressure.

The first sign of glaucoma is usually a very small loss of sight at the outside edges of the eye. Experts say most people do not know they have glaucoma until it causes a real loss of sight. Vision already lost to the disease cannot be restored.

However, the damage can be controlled and eyesight can be saved if the disease is discovered early. Doctors treat glaucoma with eye medicines or a laser light operation.

The United States Food and Drug Administration approved three new drugs last year to treat glaucoma. Two of these drugs increase the movement of fluid out of the eye. This reduces pressure in the eye. The third drug increases fluid drainage and also decreases the amount of fluid that is produced.

Researchers in Israel are developing a vaccine to treat glaucoma. Michal [me-KHAL] Schwartz is a professor at the Weizmann [VITES-mahn] Institute of Science in Rehovot [re -HO-vote]. She says tests on rats have shown that the drug Copaxone protects the optic nerve. The researchers may begin testing the vaccine in people in the next year or two. The Israeli researchers had developed Copaxone to treat the disease multiple sclerosis.

A Canadian researcher has created a device that permits people to measure their eye pressure at home. The device measures the pressure through the eyelid. Until now, measuring eye pressure could be done only at a doctor’s office. Experts say the new device will give glaucoma patients and their doctors better information about how drugs are working to control the pressure.

They also say that everyone over the age of forty should be tested for glaucoma by an eye doctor every year.

The female should pay attention to the ocular region

Cataract and glaucoma's common cause of disease is the eye gets older. Because the feminine life must be longer than the male, cataract,chanel eyeglasses, glaucoma's disease incidence rate must be higher than the male.

Moreover, diabetes, the flesh wound, the medicine have the possibility to cause cataract. The female easy to give rise to the ocular region problem in some special physiological time, for example the feminine pregnancy period eye will be quite sensitive, itself contracts diabetes' female in pregnancy period easy to aggravate, will contract diabetes' female when being pregnant the condition has the possibility worsening?

The diabetic should better before being pregnant makes the detailed fundus examination, is pregnant for three months later accepts the detailed inspection again, understood whether to have the ocular region pathological change. Itself does not have diabetes' female in pregnancy period also has the possibility to have the phenomenon which the blood sugar elevates,armani glasses, even needs to use the medicine control, also has the ocular region pathological change's possibility, needs the special attention.

Compares the attention regarding the present people contact lenses' secure question, the expert pointed out that at present the contact lenses are safe. But wears the contact lenses to be able to change around eyeball's environment, must therefore complete, the disinfection, go to the egg cleanly to wait in vain the physical link, otherwise has the possibility to cause the ocular region to be sensitive, oxygen deficit, to eye's attrition as well as ocular region infection question. Because the contact lenses are air-tight, will wear in the dry environment will have loses face does, the eye astringently and so on phenomena.

Contact lenses wearing in wears in the process to have the ill symptom, but stemmed from the consideration which had a fine external appearance still to insist that wore the contact lenses, this was very dangerous, if the ocular region inflammation, the cornea will not be transparent, looked that the thing will come under the influence, once the eye had itches, the fear light phenomenon to take down the contact lenses immediately, let the eye obtain the rest.

The professional feminine routine work is intense, eye's load is big, when reading should maintain the suitable distance, about 40cm, looked at least computer at least 70cm, frequently uses the computer to achieve every a half hour to look distant place the thing 30 seconds, let the eye obtain the rest suitably, increase the blinking number of times, prevent the eye to be dry and to be weary.

Computer's brightness should adjust shines slightly in the ambient light then,chanel sunglasses, excessively strong or weak has not favored eye's protection, especially do not use the computer in the dark environment.

Handbook of Glaucoma

By Augusto Azuara-Blanco, Vital P Costa, Richard P Wilson,

Publisher: Informa Healthcare
Number Of Pages: 280
Publication Date: 2001-11-08
Sales Rank: 2837436
ISBN / ASIN: 1841840432
EAN: 9781841840437
Binding: Hardcover
Manufacturer: Informa Healthcare
Studio: Informa Healthcare

Glaucoma is not a single disease that responds to a single treatment. A range of clinical entities is involved, including both ocular and systemic conditions. Glaucoma is difficult to diagnose, and that makes its treatment even more difficult. In this volume, the authors have written a clear and concise guide to the effective diagnosis and treatment of this not-so-simple disease. Beginning with a full classification and profile and ending with an overview of treatment options, Handbook of Glaucoma distills much of the medical literature into one straightforward reference. This guide is ideal for ophthalmologists, eye surgeons, geriatricians and any clinician attending to glaucoma patients.

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Types of Glaucoma

There are several types of glaucoma. Treatment depends on properly identifying precisely which kind is present and determining how the glaucoma may affect the person's quality of life. The goal of treatment is preservation of health.

The factor common to all types of glaucoma is damage to the optic nerve of the eye. This damage is related to the pressure inside the eye. No matter whether the pressure is high, normal or below normal, it can still cause damage. Most types of glaucoma are chronic, and are present for the person's lifetime. Some types of glaucoma occur suddenly, but most develop slowly, over months or years.

Most types of glaucoma need some form of treatment. Some people need surgery. Others may need medicine to treat the eye directly, or to treat some other health problem that is affecting the eye. Still others may need to have certain medicines stopped.

Glaucoma Suspect

Primary Angle-Closure Plateau Iris Syndrome

Primary Open-Angle Glaucoma

Normal Tension Glaucoma

(a subset of POAG)

Pediatric Glaucoma

Secondary Glaucoma

ICE syndrome

Inflammatory Glaucoma

Neovascular Glaucoma

Pigmentary Glaucoma

Pseudoexfoliative Glaucoma

Traumatic Glaucoma

Risk factors for glaucoma

Do you have any of the following risk factors? If so, you may be at risk of being diagnosed with glaucoma in your lifetime.

• Elevated intraocular pressure
• Family history of glaucoma
• Myopia - nearsightedness
• Glaucoma in the other eye
• Previous retinal detachment
• Trauma to the eye
• Diabetes
• Pigmentary dispersion syndrome
• Narrow angles
• Low systemic blood pressure
• Migraine headaches or ocular migraines
• Raynaud's Syndrome
• Blood thickening
• Abnormal visual field tests
• Unhealthy optic nerve
• Corneal endothelial dystrophy
• Pseudoexfoliation

Risk Factors and The Odds

• Family history increases risk four to nine times
• African American race increases risk 3 times (African increases risk 4 times)
• Diabetes increases risk two times
• Glaucoma in one eye, 29% chance of getting in other eye within five years
• People over age 60 are six times more likely than those under age 60

Are You at Risk for Glaucoma

Age:

1. Less than 50 years old (no points).

2. 50 to 64 years old (1 point).

3. 65 to 74 years old (2 points).

4. over 75 years of age (3 points).

Ethnic heritage:

5. African American (2 points).

6. Hispanic heritage (1 point).

Family History:

7. None of my immediate family (i.e., parents or siblings) have glaucoma (0 points).

8. One or both of my parents have glaucoma (2 points).

9. One or more of my siblings have glaucoma (3 points).

10. One or both of my parents and one or more of my siblings have glaucoma (3 points).

11. My last medical eye examination was:

a. within the past two years (0 points).

b. two to five years ago (1 point).

c. more than 5 years ago (2 points).

Add up your score: more than four points is high risk; three is moderate risk; two or less is low risk. All relatives of anyone diagnosed with glaucoma should be examined.

Common Misconceptions of Glaucoma

One of the reasons so many patients with glaucoma get worse is that they have serious misunderstandings and misconceptions about it. Here are some of the more common ones. Misconception #1: People with glaucoma lose peripheral vision. It is a misconception that patients with glaucoma lose peripheral vision. "Peripheral vision" for most people means vision off to the side. That is, when a person is looking straight ahead, peripheral vision means vision way off to the right side and way off to the left side. But that kind of "side" vision is, in fact, the last part of the vision to be lost in people with glaucoma. In most people, the initial damage to vision is a mild generalized loss of sensitivity for contrast. The first area of vision that is lost is on the nasal side of the visual field; that is, for example, for the right eye, the earliest visual loss would be just a little bit to the left-hand side of straight-ahead vision. Since this area of vision is also served by the left eye, the loss is not usually noted until most of the field is gone in one eye or a similar area is damaged in both eyes. Misconception #2: Glaucoma is a well-defined condition. "Glaucoma" encompasses such a wide variety of different conditions that the word itself is almost meaningless. For example, some patients with glaucoma can become totally blind within a period of a half an hour. Others can be damaged by the glaucomatous process so slowly that even after 20 years, there is still no awareness of any decrease in visual function. Some types of glaucoma, such as the ordinary "primary open-angle glaucoma" almost always involve both eyes, whereas other types, such as Chandler's syndrome, never involve both eyes. Some types of glaucoma are so strongly hereditary that 50% of the members of a family are likely to be affected, whereas others have absolutely no familial tendencies at all. To tell a person that he has "glaucoma" doesn't really tell the person anything meaningful. Rather, the physician should try to explain as carefully as possible what the patient should expect: "You have a condition that has already caused a major amount of damage; if nothing is done, it is likely to get worse over the next three or four years," or: "With your type of glaucoma you probably won't have any discomfort or have any other clues that it's getting worse until the damage is marked. So, you need a glaucoma specialist to monitor your condition." In short, it is not the glaucoma that is treated, it is the person who needs to be treated, because it is the disease's effect on the person that is the only important consideration. Misconception #3: People who have glaucoma have to use their drops forever. It is a misconception that once individuals "start on drops" they must use them for the rest of their lives. However, behind that misconception is a truth that frequently does apply: specifically, that the tendency always to get worse is present in many types of glaucomas and, therefore, vigilance may be necessary for the person's entire life. In some people, the need for medications to control the intraocular pressure may spontaneously disappear. If drops or other medications need to be continued, it is not because the person is taking the drops that the drops need to be continued. Rather, it is because the underlying problem with the glaucoma continues to exist and some means to manage it continues to be necessary. Misconception #4: Surgery is appropriate only in desperate cases. The idea that one starts with weaker drops, progresses to stronger medicine, and only as a last resort becomes a candidate for surgery is another misconception about glaucoma. This misconception is related to the variety of ways in which glaucoma presents itself. Some types of glaucoma are best treated right from the start with surgery. For example, the commonest type of glaucoma that occurs in infants usually responds well to surgery but never responds adequately to medicines. On the other hand, with certain types of glaucoma, it is best to avoid surgery, because the risk associated with the surgery is far greater than the potential damage that would occur if the surgery weren't done. Misconception #5: We can tell whether or not glaucoma is being controlled by monitoring the level of the intraocular pressure. It is a misconception to think that control of glaucoma is measured in terms of the intraocular pressure. It is true that glaucoma is damage to the tissues of the eye that is at least partially caused by pressure higher than the eye can tolerate. Nevertheless, people can go blind even though their intraocular pressure is fairly constantly as low as 12 mm Hg, well below the so-called "normal" level of pressure. Others can maintain pressures of 25 mm Hg -- much higher than "normal" -- for many, many years and yet never develop any damage at all. Control of glaucoma can be defined only in terms of whether or not there is increasing damage. Where the damage is increasing, the glaucoma must be defined as "uncontrolled," regardless of the pressure. Where it is not increasing, the glaucoma must be defined as "controlled," regardless of the pressure. Misconception #6: What the glaucoma patient does doesn't really make very much difference. A particularly tragic misconception about glaucoma is that what the patient does doesn't really make very much difference. In fact, how a person manages his or her life is probably the single most important factor determining whether that person maintains his or her sight. Choosing a competent doctor is an important part of that management, as is helping the doctor do his or her job competently. The patient is really the senior partner and the physician the junior partner. The patient has the responsibility of being alert to how he or she is doing, both from the point of view of general health, quality of life, and visual function, and of passing that information on to the physician. The physician has the responsibility of listening, understanding, and drawing appropriate conclusions. Patients are responsible for educating themselves, using the physician to help them in that process. The more a patient knows, the better it is. An important example is patient awareness that general health significantly affects the course of glaucoma damage. For example, to help maintain vision, the overweight person should lose weight and the sedentary person should exercise. Perhaps the most important thing to understand about glaucoma is that each case is different and that the greatest success in terms of maintenance of quality of life as related to vision occurs when the individual patient really takes responsibility for his or her own well-being and then works with a knowledgeable, competent physicians, who truly listens and truly cares for the person as an individual.

What happens in Glaucoma?

What is glaucoma?
Glaucoma is an increase in the intraocular pressure (IOP) in the eye. If left unchecked it will do permanent damage to the inner structure of the eye and eventually result in blindness.

What happens in Glaucoma?
When Gaucoma occurs, the pressure in the eye is no longer being regulated which results in elevated intraocular pressure. The fluid in the anterior segment of the eye is called aqueous humor and is produced by the ciliary body. Aqueous flows from behind the iris, through the pupil and into the anterior chamber, bringing nutrients and eliminating waste products from the lens and cornea. Aqueous eventually exits through the drainage angle at the peripheral iris through a sponge-like tissue and into the venous return. This drainage system is responsible for maintaining the intraocular pressure in the eye. The normal intraocular pressure is between 10 mmHg and 20 mmHg in most animals. Pressures that exceed 20mmHg are of concern while those above 30 mmHg start to cause irreversible damage to the internal structures of the eye. Glaucoma is a disease that presents itself in five stages:
1. Initial insult or underlying condition
2. Obstruction of the aqueous outflow
3. An increase in the intraocular pressure (> 30 mmHg) which affects the health of the optic nerve head
4. Permanent retinal cell damage along with optic nerve degeneration and atrophy
5. Visual field loss and blindness

What causes Glaucoma?
In both humans and animals, glaucoma can be classified into two main categories: primary and secondary. Glaucoma can affect canines at any age and certain breeds are more prone to this disease. In felines primary glaucoma is rare; it is more common for them to develop secondary glaucoma.

Primary Glaucoma is due to a problem with the drainage angle (narrow-angle glaucoma or goniodysgenesis) and is often an inherited disease. Several breeds such as Basset Hounds, Beagles, Boston Terriers, Cocker Spaniels and Shar-Peis are prone to this disease.

Secondary Glaucoma usually has an obvious cause such as trauma, inflammation, intraocular bleeding, lens luxation or a tumor. Usually one eye is affected. If the cause can be eliminated then the glaucoma may be easier to control and can often be eliminated.

What are the clinical signs?
The early symptoms of Gaucoma may include redness, conjunctivitis, tearing, and eye discomfort. As the disease progresses and the pressure elevates, the symptoms become more obvious. As the intraocular pressure rises, the cornea becomes cloudy, the pupil will dilate, and eye will become redder. If this elevated pressure is not treated, the globe will eventually enlarge (buphthalmia). Unfortunately it takes only a short period of time (48 –72 hours) for an elevated IOP to cause irreversible damage and blindness.

Acute glaucoma with a dilated pupil and scleral injection

Husky with acute glaucoma (dilated pupil)

How is Glaucoma diagnosed?
There are several testing procedures for detecting Glaucoma or the predisposition for Glaucoma. The most useful methods are tonometry, gonioscopy and direct ophthalmic examination. Tonometry is the measuring of the intraocular pressure by means of an instrument. Development of the applanation tonometer (TonoPen) and rebound tonometer (TonoVet) have provided the veterinarian a reliable approach to evaluating the IOP. A gonioscopic examination is the visualization of the drainage angle with the aid of a specialized contact lens. Performing a direct ophthalmic examination will allow a veterinarian to evaluate other signs of glaucoma and evaluate the integrity of the internal structures of the eye.

Can Glaucoma be treated?
If caught early, you have a better chance of controlling glaucoma pharmacologically. The antiglaucomatous drugs available aim to decrease the production of aqueous or enhance its outflow from the eye. Surgical intervention through cryosurgery or laser surgery can destroy areas of the ciliary body and thus reduce aqueous production. Another option in a visual eye is a gonioimplant. This implant allows the aqueous to escape from the eye through an alternative route. Eventually most gonioimplants are blocked by scar tissue or are encapsulated by the overlying tissue and no longer allow fluid to exit the eye.

What happens with blind Glaucomatous eyes?
When glaucomatous eyes are no longer responsive to treatment and become painful, there are several options to make the eye more comfortable. They include the following:
1. Diode laser transscleral cyclophotocoagulation procedure will destroy the ciliary body and decrease the IOP
2. Intravitreal gentamicin injection will destroy the ciliary body and decrease the IOP
3. Evisceration of the globe with implantation of a silastic sphere
4. Enucleation is removal of the eye with intraobital silastic sphere implant

source: eyenet

Fast Facts About Glaucoma

1. Glaucoma is the leading cause of blindness in the world.
   
2. More than 1,000,000 people are totally blind from glaucoma in China.
   
3. Several million more people have elevated intraocular pressure.
   
4. About 2% of the population age 40-50 and 8% over 70 have elevated intraocular pressure.
   
5. Glaucoma affects people of all ages and all races.
   
6. Most blindness from glaucoma is needless and could have been prevented if detected and treated in time.
   
7. Most patients have no symptoms from glaucoma.
   
8. Blindness from glaucoma usually begins with loss of peripheral vision. Central vision is usually maintained until the late stages. By the time the patient notices visual loss, damage is advanced.
   
9. Factors which predispose to glaucoma include myopia, black race, and a family history of glaucoma. Thyroid disease, diabetes, and high blood pressure may be associated to some degree.
   
10. Intraocular pressure can be measured by a simple office test called tonometry. This test is the only reliable method of detecting elevated intraocular pressure.
    
11. Signs of disorders within the eye which could lead eventually to elevated intraocular pressure can be determined by a thorough eye examination by an ophthalmologist.
    
12. Fully half of all persons with damage from glaucoma are unaware of it.
    
13. In a nationwide phone survey conducted a few years ago by Prevent Blindness America, blindness ranked third after cancer and heart disease as people's major fear.
    
14. However, only 20% of people knew that glaucoma was related to elevated pressure within the eye. Another 50% had heard of glaucoma, but weren't sure what it was, while 30% had never heard of it.
    
15. Of the 20% who knew about glaucoma, most thought either that people affected could tell because they would have symptoms, that it was easily cured, or that it did not lead to blindness.
    
16. Despite that fact that glaucoma is roughly as common as high blood pressure and diabetes, the widespread public lack of familiarity with glaucoma results in thousands of blindness annually, most of which could have been prevented.