2. INTRODUCTION-
Glaucoma is a condition that causes damage to your eye's optic nerve and gets worse over
time. It's often linked to increase of pressure inside your eye. Glaucoma tends to be inherited
and may not show up until later in life.
3. • The increased pressure, called intraocular pressure, can damage the optic nerve, which
transmits images to your brain. If the damage continues, glaucoma can lead to
permanent vision loss. Without treatment, glaucoma can cause total permanent
blindness within a few years.
CAUSES-
• It’s the result of an intrinsic deterioration of the optic nerve, which leads to high fluid
pressure on the front part of the eye.
• Normally, the fluid, called aqueous humor, flows out of your eye through a mesh-like
channel. If this channel gets blocked, the liquid builds up.
• The reason for the blockage is unknown, but doctors do know it can be inherited,
meaning it’s passed from parents to children.
4. • Less common causes include a blunt or chemical injury to your eye, severe eye
infection, blocked blood vessels inside the eye, and inflammatory conditions.
• It’s rare, but sometimes eye surgery to correct another condition can bring it on. It
usually affects both eyes, but it may be worse in one than the other.
5.
6. TYPES OF GLAUCOMA-
The two major categories of glaucoma are-
a) Open-angle glaucoma (OAG)
b) Narrow angle glaucoma.
The "angle" in both cases refers to the drainage angle inside the eye that controls the
outflow of the watery fluid (aqueous) that is continually being produced inside the eye.
Open angle glaucoma- If the aqueous can access the drainage angle, the glaucoma.
Narrow angle glaucoma- If the drainage angle is blocked and the aqueous cannot reach it,
the glaucoma.
Variations of Open angle glaucoma include- Primary open angle glaucoma (POAG),
Normal-tension glaucoma (NTG), Pigmentary glaucoma, Pseudoexfoliation glaucoma,
Secondary glaucoma and Congenital glaucoma.
Variations of Narrow angle glaucoma include- Acute angle closure glaucoma, Chronic
angle closure glaucoma, and Neovascular glaucoma.
7. 2. Acute angle-closure glaucoma- Also called narrow-angle glaucoma, acute angle-closure glaucoma
produces sudden symptoms such as eye pain, headaches, halos around lights, dilated pupils, vision loss, red eyes,
nausea & Vomiting.
These signs constitute a medical emergency. The attack may last for a few hours, and then return again for
another round, or it may be continuous without relief. Each attack can cause progressively more vision loss.
3. Normal-tension glaucoma- Like Primary open angle glaucoma, normal-tension glaucoma (also called
normal-pressure glaucoma, low-tension glaucoma or low-pressure glaucoma) is a type of open-angle glaucoma
that can cause visual field loss due to optic nerve damage. But in normal-tension glaucoma, the eye's IOP
remains in the normal range.
Also, pain is unlikely and permanent damage to the eye's optic nerve may not be noticed until symptoms such as
tunnel vision occur.
1. Primary open-angle glaucoma- This common type of glaucoma gradually reduces your peripheral
vision without other symptoms. By the time you notice it, permanent damage already has occurred.
If your IOP remains high, the destruction caused by POAG can progress until tunnel vision develops, and you
will be able to see only objects that are straight ahead. Ultimately, all vision can be lost, causing blindness.
8. The cause of normal-tension glaucoma is not known. But many doctors believe it is related to poor blood flow
to the optic nerve. Normal-tension glaucoma is more common in those who are Japanese, are female and/or
have a history of vascular disease.
4. Pigmentary glaucoma- This rare form of glaucoma is caused by clogging of the drainage angle of the
eye by pigment that has broken loose from the iris, reducing the rate of aqueous outflow from the eye. Over
time, an inflammatory response to the blocked angle damages the drainage system.
You are unlikely to notice any symptoms with pigmentary glaucoma, though some pain and blurry vision may
occur after exercise. Pigmentary glaucoma most frequently affects white males in their mid-30s to mid-40s.
5. Secondary glaucoma- Symptoms of chronic glaucoma following an eye injury could indicate
secondary glaucoma, which also may develop with presence of eye infection, inflammation, a tumor or
enlargement of the lens due to a cataract.
6. Congenital glaucoma- This inherited form of glaucoma is present at birth, with 80 percent of cases
diagnosed by age one. These children are born with narrow angles or some other defect in the drainage system
of the eye.
It's difficult to spot signs of congenital glaucoma, because children are too young to understand what is
happening to them. If you notice a cloudy, white, hazy, enlarged or protruding eye in your child, consult your
eye doctor. Congenital glaucoma typically occurs more in boys than in girls.
9. Who Gets Glaucoma?
It mostly affects adults over 40, but young adults, children, and even infants can have it. African-Americans
tend to get it more often, when they're younger, and with greater vision loss.
It is mainly affects-
• African-American, Irish, Russian, Japanese, Hispanic, Inuit, or Scandinavian descent.
• Who have a family history of glaucoma.
• Who have poor vision.
• Who have diabetes.
• One who used to take certain steroid medications, like prednisone.
• Who have had trauma to the eye or eyes.
Symptoms-
Most people don’t have any. The first sign is often a loss of peripheral, or side, vision. That can go unnoticed
until late in the disease. That’s why glaucoma is often called the "sneak thief of vision”.
Detectable Symptoms are-
Seeing halos around lights
Vision loss
10. Redness in the eye
Eye that looks hazy (particularly in infants)
Nausea or vomiting
Eye pain
Narrowed vision (tunnel vision)
Diagnosis, Screening-
During routine eye exams, a Tonometer is used to measure intraocular pressure, or IOP.
An eye typically is numbed with eye drops, and a small probe gently rests against an eye's surface.
Other Tonometers send a puff of air onto your eye's surface.
An abnormally high Intraocular pressure reading indicates a problem with the amount of fluid (aqueous
humor) in the eye. Either the eye is producing too much fluid, or it's not draining properly.
Normally, IOP should be below 21 mmHg (millimeters of mercury) — a unit of measurement based on
how much force is exerted within a certain defined area.
11. If patient’s intraocular pressure is higher than 30 mmHg, the risk of vision loss from
glaucoma is 40 times greater than someone with intraocular pressure of 15 mmHg or
lower. This is why glaucoma treatments such as eye drops are designed to keep IOP low.
Other methods of monitoring glaucoma involve the use of sophisticated imaging
technologies such as-
a) Scanning lase polarimetry (SLP).
b) Optical coherence tomography (OCT).
c) Confocal scanning laser ophthalmoscopy — to create baseline images and
measurements of the eye's optic nerve and internal structures.
Then, at specified intervals, additional images and measurements are taken to make sure no
changes have occurred over time that might indicate progressive glaucoma damage.
12. 1. Visual field testing- Visual field testing involves staring straight ahead into a machine
and clicking a button when you notice a blinking light in your peripheral vision. The visual
field test may be repeated at regular intervals to make sure you are not developing blind
spots from damage to the optic nerve or to determine the extent or progression of vision loss
from glaucoma.
2. Gonioscopy- It also may be performed to make sure the aqueous humor (or "aqueous")
can drain freely from the eye. In gonioscopy, special lenses are used with a biomicroscope
to enable your eye doctor to see the structure inside the eye (called the drainage angle) that
controls the outflow of aqueous and thereby affects intraocular pressure.
Ultrasound biomicroscopy is another technique that may be used to evaluate the drainage
angle.
TESTS FOR GLAUCOMA-
13.
14. Pilocarpine-
– Pilocarpine occurs in solid form. It is soluble in Water, chloroform, alcohol. It is
sparingly soluble in Ether, Benzene but completely insoluble in petroleum ether.
– It’s melting point is 204-205 °C.
– It stable in air but affected by light.
– On heating it gets decomposed and emits toxic fumes.
– Pilocarpine is a slowly hydrolyzed muscarinic agonist with no nicotinic effects.
Pilocarpine is used as a miotic and in the treatment of glaucoma.
– Pilocarpine is a Cholinergic Receptor Agonist. The mechanism of action of pilocarpine is
as a Cholinergic Agonist, and Cholinergic Muscarinic agonist.
16. It’s should not be use in-
– Pilocarpine reduces the amount of fluid in the eye, which decreases
pressure inside the eye.
– Pilocarpine ophthalmic (for the eyes) is used to treat glaucoma or
ocular hypertension (high pressure inside the eye).
– Pilocarpine ophthalmic may also be used for other purposes not listed
in this medication guide.
– It should not be prescribed to patient who has allergy to pilocarpine, or
if patient have uveitis or pupillary block glaucoma.
17. • You should not use this medication if you are allergic to pilocarpine, or if
you have uveitis or pupillary block glaucoma.
• Before using pilocarpine ophthalmic, tell your doctor if you are allergic to
any drugs.
• FDA pregnancy category C. This medication may be harmful to an unborn
baby. Tell your doctor if you are pregnant or plan to become pregnant during
treatment.
• It is not known whether pilocarpine ophthalmic passes into breast milk or if
it could harm a nursing baby. Do not use this medication without telling
your doctor if you are breast-feeding a baby.
18. Mechanism of Action-
– Pilocarpine is a cholinergic parasympathomimetic agent. It increase secretion by the
exocrine glands, and produces contraction of the iris sphincter muscle and ciliary muscle
(when given topically to the eyes) by mainly stimulating muscarinic receptors.