Definition of GlaucomaDefinition of Glaucoma

Glaucoma is a group of eye diseases that damage  is a group of eye diseases that damage the optic nerve. The optic nerve is the main the optic nerve. The optic nerve is the main nerve to the eye (located in the back of the nerve to the eye (located in the back of the eye) that is responsible for transmitting eye) that is responsible for transmitting electrical impulses to the brain. Damage electrical impulses to the brain. Damage usually occurs as a result of elevated pressure usually occurs as a result of elevated pressure of the fluid (aqueous humor) in the eye. This of the fluid (aqueous humor) in the eye. This damage results in gradual visual changes and damage results in gradual visual changes and then loss of vision.then loss of vision.

Types Types

Open-angle glaucomaOpen-angle glaucoma Closed angle glaucomaClosed angle glaucoma

Open-angle glaucomaOpen-angle glaucoma

(Also called primary open-angle glaucoma (Also called primary open-angle glaucoma and chronic glaucoma) accounts for 90 percent and chronic glaucoma) accounts for 90 percent of all glaucoma cases and occurs when the of all glaucoma cases and occurs when the trabecular meshwork becomes blocked and the trabecular meshwork becomes blocked and the fluid can't get to the normal drainage canals. fluid can't get to the normal drainage canals. This blockage results in fluid build-up and This blockage results in fluid build-up and intraocular pressure. The fluid build-up intraocular pressure. The fluid build-up happens gradually.happens gradually.

Closed angle glaucomaClosed angle glaucoma

(Also called acute glaucoma or angle closure (Also called acute glaucoma or angle closure glaucoma), accounts for about 9 percent of all glaucoma), accounts for about 9 percent of all glaucoma cases and occurs when the opening glaucoma cases and occurs when the opening between the cornea and iris narrows, such that between the cornea and iris narrows, such that the fluid cannot get to the trabecular the fluid cannot get to the trabecular meshwork and normal drainage channels. This meshwork and normal drainage channels. This narrowing results in fluid build-up and narrowing results in fluid build-up and intraocular pressure. The fluid build-up intraocular pressure. The fluid build-up happens very quickly.happens very quickly.

Other less common glaucomas Other less common glaucomas include:include:

Normal tension glaucomaNormal tension glaucoma: optic nerve is damaged even : optic nerve is damaged even though intraocular pressure is consistently within a normal though intraocular pressure is consistently within a normal rangerange

Congenital glaucomaCongenital glaucoma: incorrect or incomplete development : incorrect or incomplete development of the eye's drainage canals during the prenatal periodof the eye's drainage canals during the prenatal period

Childhood glaucomaChildhood glaucoma: open-angle glaucoma in infancy, : open-angle glaucoma in infancy, childhood or adolescencechildhood or adolescence

Secondary glaucomaSecondary glaucoma: occurs as a result of eye injury, : occurs as a result of eye injury, inflammation or tumor, or in advanced cases of inflammation or tumor, or in advanced cases of cataracts or  or diabetesdiabetes

Causes and Risk Factors of GlaucomaCauses and Risk Factors of GlaucomaSeveral factors that can put a person "at risk" for Several factors that can put a person "at risk" for

developing developing glaucomaglaucoma:: Family history of glaucoma Family history of glaucoma - There is a 20 percent - There is a 20 percent

chance of developing glaucoma of a parent had it, and chance of developing glaucoma of a parent had it, and 50 percent chance if a sibling has it.50 percent chance if a sibling has it.

Age Age - If the person is 65 to 79 years of age, there is a 3 - If the person is 65 to 79 years of age, there is a 3 percent chance of developing glaucoma. If the person is percent chance of developing glaucoma. If the person is 80 years of age or older, there is a 14 percent of 80 years of age or older, there is a 14 percent of developing glaucoma.developing glaucoma.

Medical conditionsMedical conditions, such as morning , such as morning headaches, headaches, diabetesdiabetes, lupus, , lupus, Crohn's diseaseCrohn's disease, , rheumatoid rheumatoid arthritisarthritis, myopia (nearsightedness), and , myopia (nearsightedness), and high blood pressurehigh blood pressure

Use of Use of topical steroid topical steroid (prednisone or cortisone) (prednisone or cortisone) medicationsmedications

RaceRace - Blacks are three to four times more likely - Blacks are three to four times more likely than Caucasians to develop glaucoma. Asians and than Caucasians to develop glaucoma. Asians and Eskimos are more likely to develop glaucoma than Eskimos are more likely to develop glaucoma than Caucasians.Caucasians.

Abnormally Abnormally high intraocular pressurehigh intraocular pressure Previous eye Previous eye injuriesinjuries Recurrent blurry visionRecurrent blurry vision PainPain around the eyes after watching TV or leaving around the eyes after watching TV or leaving

a dark theatera dark theater

PathophysiologyPathophysiologyThere are two accepted theories regarding how increased IOPThere are two accepted theories regarding how increased IOPdamages the optic nerve in glaucoma. damages the optic nerve in glaucoma. The direct mechanical theoryThe direct mechanical theory

It suggests that high IOP damages the retinal layer It suggests that high IOP damages the retinal layer as it passes through the optic nerve head. as it passes through the optic nerve head.

The indirect ischemic theoryThe indirect ischemic theoryIt suggests that high IOP compresses the It suggests that high IOP compresses the

microcirculation in the optic nerve head, resulting in cell injury microcirculation in the optic nerve head, resulting in cell injury and death. Some glaucomas appear as exclusively mechanical, and and death. Some glaucomas appear as exclusively mechanical, and some are exclusively ischemic types. Typically, most cases are a some are exclusively ischemic types. Typically, most cases are a combination of both.combination of both.

Symptoms of GlaucomaSymptoms of Glaucoma

Known as the "sneak thief" of sight, Known as the "sneak thief" of sight, open-angle open-angle glaucomaglaucoma has no  has no early warning signs or symptoms. However, as the disease early warning signs or symptoms. However, as the disease progresses a person may experience:progresses a person may experience:

Tiny blind spots appear at the edges of the visual field Tiny blind spots appear at the edges of the visual field (peripheral or side vision) that slowly get larger and spread(peripheral or side vision) that slowly get larger and spread

Blurred visionBlurred vision Appearance of colored halos around lightsAppearance of colored halos around lights Adjustment problems on entering a dark roomAdjustment problems on entering a dark room Repeated difficulties that new eyeglass prescriptions do not Repeated difficulties that new eyeglass prescriptions do not

helphelp Peripheral (side) vision is decreasingPeripheral (side) vision is decreasing

The symptoms of The symptoms of closed angle glaucomaclosed angle glaucoma are: are: Severely blurred visionSeverely blurred vision Severe eye and head painSevere eye and head pain Nausea or vomitingNausea or vomiting Appearance of rainbow-colored halos around Appearance of rainbow-colored halos around

bright lightsbright lights Rapid loss of visionRapid loss of vision

Diagnosis Diagnosis There are four (4) important factors in the There are four (4) important factors in the

diagnosis of diagnosis of glaucomaglaucoma: intraocular pressure, : intraocular pressure, the condition of the optic nerve, the patient's the condition of the optic nerve, the patient's visual field and the angle where the iris meets visual field and the angle where the iris meets the cornea. To detect these factors, the the cornea. To detect these factors, the ophthalmologist will do the following ophthalmologist will do the following diagnostic tests:diagnostic tests:

TonometryTonometry

TonometryTonometry - used to measure intraocular pressure. Drops  - used to measure intraocular pressure. Drops are put in the eyes to numb the eye and then the doctor are put in the eyes to numb the eye and then the doctor measures the eye pressure, using an instrument called a measures the eye pressure, using an instrument called a tonometer. This instrument measures the inner pressure of tonometer. This instrument measures the inner pressure of the eye by determining how much pressure is necessary to the eye by determining how much pressure is necessary to cause a slight indentation on the outer part of the eye.cause a slight indentation on the outer part of the eye.

OphthalmoscopyOphthalmoscopy - used to examine the inside of the eye,  - used to examine the inside of the eye, the optic nerve and the patient's field of vision. Drops are the optic nerve and the patient's field of vision. Drops are put in the eyes to dilate the pupil and then the doctor uses put in the eyes to dilate the pupil and then the doctor uses an instrument called an ophthalmoscope that lights up and an instrument called an ophthalmoscope that lights up and magnifies the inside of the eye.magnifies the inside of the eye.

If the intraocular pressures are not within normal If the intraocular pressures are not within normal range or if the optic nerve looks unusual, the range or if the optic nerve looks unusual, the doctor may do a perimetry or a gonioscopy:doctor may do a perimetry or a gonioscopy:

PerimetryPerimetry - a special test that produces a map  - a special test that produces a map of the complete field of vision.of the complete field of vision.

GonioscopyGonioscopy - a test to check whether the angle  - a test to check whether the angle where the iris meets the cornea is open or where the iris meets the cornea is open or closed.closed.

PerimetryPerimetry

GonioscopyGonioscopy

Treatment of GlaucomaTreatment of Glaucoma

There is no cure for There is no cure for glaucomaglaucoma, but it can be , but it can be controlled. Ophthalmologists use medication controlled. Ophthalmologists use medication and surgery to prevent further vision loss. and surgery to prevent further vision loss. These treatment methods are used to bring the These treatment methods are used to bring the intraocular pressure under control.intraocular pressure under control.

MedicationMedicationNearly all glaucoma can be treated successfully with topical medications Nearly all glaucoma can be treated successfully with topical medications

(applied directly to the eyes, such as eye drops or eye ointments) or oral (applied directly to the eyes, such as eye drops or eye ointments) or oral medications (taken by mouth). There are six medications available to medications (taken by mouth). There are six medications available to treat glaucoma:treat glaucoma:

MioticsMiotics are eye drops that help open the drainage canals and increase  are eye drops that help open the drainage canals and increase the flow of aqueous humor out of the eye. This type of medication the flow of aqueous humor out of the eye. This type of medication includes pilocarpine (Isopto Carpine, Pilocar, Pilopine), carbachol and includes pilocarpine (Isopto Carpine, Pilocar, Pilopine), carbachol and echothiophate.echothiophate.

Epinephrine compoundsEpinephrine compounds are eye drops that lower the intraocular  are eye drops that lower the intraocular pressure by increasing the rate of aqueous humor flow out of the eye. pressure by increasing the rate of aqueous humor flow out of the eye. This type of medication includes dipivefrin (Propine) and Epifrin.This type of medication includes dipivefrin (Propine) and Epifrin.

Beta-blockersBeta-blockers (available as eye drops or pills) help decrease the rate at  (available as eye drops or pills) help decrease the rate at which the aqueous humor flows into the eye. This type of medication which the aqueous humor flows into the eye. This type of medication includes topical timolol (Timoptic), levobunolol (Betagan), betaxolol includes topical timolol (Timoptic), levobunolol (Betagan), betaxolol (Betaoptic-S), Iopidine and Ocupress. Additionally, this type of (Betaoptic-S), Iopidine and Ocupress. Additionally, this type of medication can also be taken orally. Oral medications include medication can also be taken orally. Oral medications include propranolol, timolol, atenolol and nadolol.propranolol, timolol, atenolol and nadolol.

Carbonic anhydrase inhibitorsCarbonic anhydrase inhibitors (available as pills or eye  (available as pills or eye drops) help reduce aqueous humor flow into the eye. This type drops) help reduce aqueous humor flow into the eye. This type of medication includes oral acetazolamide (Diamox), of medication includes oral acetazolamide (Diamox), methazolamide (Neptazane) and chlorpropamide (Daranide), methazolamide (Neptazane) and chlorpropamide (Daranide), as well as topical dorzolamide (Trusopt).as well as topical dorzolamide (Trusopt).

Alpha adrenergic agonistsAlpha adrenergic agonists are topical medications used to  are topical medications used to reduce the aqueous humor production and increase aqueous reduce the aqueous humor production and increase aqueous humor outflow. This type of medication includes apraclonidine humor outflow. This type of medication includes apraclonidine (Iopidine) and brimonidine (Alphagan).(Iopidine) and brimonidine (Alphagan).

Prostaglandin analoguesProstaglandin analogues are topical medications that help  are topical medications that help lower intraocular pressure by increasing uveoscleral outflow lower intraocular pressure by increasing uveoscleral outflow (outflow through the soft tissues of the front of the eye [iris (outflow through the soft tissues of the front of the eye [iris and ciliary body]). This type of medication includes and ciliary body]). This type of medication includes latanoprost (Xalatan).latanoprost (Xalatan).

Surgical managementSurgical management Argon laser trabeculoplasty (ALT)Argon laser trabeculoplasty (ALT) Trabeculectomy Trabeculectomy Laser peripheral iridotomy Laser peripheral iridotomy Surgical iridotomy Surgical iridotomy