Glaucoma is the second leading cause of blindness worldwide according to the WHO. It is a group of eye diseases that damage the optic nerve and causes vision loss, usually due to increased intraocular pressure. There are two main types - open-angle glaucoma which is most common, and closed-angle glaucoma which is more urgent. Detection involves measuring eye pressure, examining the optic nerve and retina, and visual field testing. Treatment goals are to lower eye pressure through medications, laser trabeculoplasty, or surgery such as trabeculectomy or tube shunt implantation to slow disease progression.

1. HIMADRI NATH
SEM –II ,M.Sc ZOOLOGY
ROLL:BGC/ZOOI NO:14101
BARASAT GOVT. COLLEGE

2. GLAUCOMA- Definition
Glaucoma can be considered a generic
name for a group of diseases causing optic
neuropathy ( disc cupping ) and visual field
loss usually , but not always, in the
presence of raised IOP, it is increasingly
being realised that other factors- such as
optic nerve head perfusion, are
concomitantly responsible for optic
neuropathy in adult glaucoma.

3. EPIDEMIOLOGY
Glaucoma is the second leading cause of blindness in the world, according to the
World Health Organization.
As of 2010, there were 60.5 million people in the world with glaucoma.
By 2020, the prevalence is projected to increase to 79.6 million worldwide .
On the basis of population based studies from India ,estimated that 11.2 million
person affected with Glaucoma. Among them 6.48 million with POAG,2.54
million with PACG,2.28 million with secondary glaucoma.
References:
1.QuigleyHA,BromanAT.(2006) “The number of people with glaucoma worldwide in 2010 and 2020”,Br J
Ophthalmol;90(3):262-267
2.George R,Ramesh S Ve,Vijaya L.(2010) “Glaucoma in India:Estimated Burden of Disease” J Glaucoma;19:391-
397
3. Kingman, Sharon (2004). "Glaucoma is second leading cause of blindness globally". Bulletin of the World
Health Organization 82 (11): 887–888.

4. THE HEALTHY EYE
• Light rays enter the eye
through the cornea, pupil
and lens.
• These light rays are
focused directly onto the
retina, the light-sensitive
tissue lining the back of the
eye.
• The retina converts light
rays into impulses; sent
through the optic nerve to
your brain, where they are
recognized as images.

5. Aqueous Humor Dynamics
In the front of the eye is a space called the anterior chamber.
A clear fluid ,called aqueous humor produce from ciliary body ,passes
through pupil to enter into anterior chamber and nourishes the nearby
tissues. The fluid leaves the anterior chamber at the angle where the
cornea and iris meet, called trabecular meshwork. From there it drains
into Canal of Schlemm which inturn opens into aqueous veins and
reabsorbed.

6. Sometimes the aqueous humor passes slowly or blocked through
the meshwork drain. Then the fluid builds up, the pressure inside
the eye rises(IOP-Increased intraocular pressure). Unless the
pressure at the front of the eye is controlled, it can damage the optic
nerve and cause vision loss. This is the main cause of Glaucoma.
IOP & GLAUCOMA

7. TYPES OF GLAUCOMA
Two main categories of glaucoma:
• Open-angle glaucoma: the most common form of glaucoma -
(the most common form that affects approximately 95% of
individuals)
• Closed-angle glaucoma: a less common and more urgent form
of glaucoma.
Other Types of glaucoma:
Normal-Tension Glaucoma
Congenital glaucoma
Secondary glaucoma

8. OPEN-ANGLE Glaucoma:
• Trabecular meshwork becomes less efficient at draining aqueous
humor.
• Intraocular pressure (IOP) builds up, which leads to damage of
the optic nerve.
• Damage to the optic nerve occurs at different eye pressures
among different patients.
• Typically, glaucoma has no symptoms in its early stages.

9. CLOSED -ANGLE(or narrow-angle) glaucoma:
• The drainage angle of
trabecular meshwork
becomes blocked by the iris.
• IOP builds up very fast.
• Symptoms include severe
eye or brow pain, redness of
the eye, decreased or blurred
vision.
• Must be treated as a medical
Emergency-should visit
ophthalmologist immediately.

10. CLOSED -ANGLE(or narrow-angle) glaucoma:

11. NORMAL-TENSION Glaucoma
Normal-tension glaucoma occurs when there is damage to the optic nerve
detected in patient who has completely normal Inter Ocular Pressure (IOP).It has
the same characteristics of POAG. Lowering eye pressure through medication
sometimes slows the progress of the disease, but this type of glaucoma may
worsen despite low pressure. Treatment is generally the same as for open-angle
glaucoma with high eye pressure.
OPTIC CUP PRODUCED IN RETINA

12. CONGENITAL Glaucoma
Congenital Glaucoma results as a condition from birth.Children are born
with conditions.such as abnormal development of anterior chember
angle which prohibt the normal drainage of fluid from the eyes,which
cause an increase in pressure within the eye, subsequent retinal and
optical disc damage.

13. Secondary Glaucoma
Glaucoma can develop as a complication from other conditions
including:
Eye injuries
Uveitis (internal eye inflammation)
Pigment dispersion
Diabetes (Neovascular glaucoma)
Steroid use
Normal vision Glaucoma affected vision

14. Detection of Glaucoma
Regular glaucoma check-ups include two routine eye tests:
1.Tonometry – eye pressure test IOP
2.Ophthalmoscopy --using a magnifying instrument
(ophthalmoscope) and a light source.
Additional tests:
Perimetry : The perimetry test is also called a visual field test.
Gonioscopy : is a painless eye test that checks if the angle where the iris
meets the cornea is open or closed, showing if either open angle or closed
angle glaucoma is present.

15. Tonometry measures intraocular pressure either by the force required to
flatten a constant area of the cornea (e.g. Goldmann tonometry) or by
the area flattened by a constant force.
Goldmann tonometer: Stationary device requires anesthesia drops, requires contact
with cornea and is attached to a slit lamp – usually is used by an Ophthalmologist.
TONOMETRY

16. Non-contact tonometry or air-puff tonometry:
This type of tonometer uses a rapid air pulse to applanate the cornea. Intraocular
pressure is estimated by detecting the force of the air jet at the instance of applanation.
In most cases a stationary unit,
Does not require anesthetic drops
TONOMETRY

17. Tono-pen - is a portable electronic, digital pen-like instrument that
determines IOP by making contact with the cornea, after use of
topical anesthetic eye drops – tip covers are used between the
patients.
TONOMETRY

18. The newest Advancement in tonometry is DIATON TONOMETER –
It measures intraocular pressure (IOP) through the Eyelid.
TONOMETRY

19. •Safe
•Quick
•Efficient
•Painless
•Noninvasive
Can be used on
Children and
Adults
DIATON TONOMETRY

20. OPTHALMOSCOPY
Eye drops may be placed in the eyes to dilate the pupils.
Special magnifying lenses are used to examine the retina and optic nerve
for damage.
Normal optic nerve Suspicious Optic Nerve

21. Slit Lamp & Gonioscopy
A special microscope called a slit lamp is used to examine the structures of
the eye.
A gonioscopy lens may be used to view the drainage angle.

22. PERIMETRY OR VISUAL FIELD TEST
Perimetry is an essential method used to determine if there is any loss of the visual field .
Peripheral (side) vision is tested with a perimeter.

23. GLAUCOMA TREATMENT
The goal is to decrease the eye pressure
The three main categories of treatment are:
1. Medication
2. Laser trabeculoplasty
3. Conventional surgery
Unfortunately, these treatments will not
reverse any existing damage but they can
slow the progression of the disease

24. DRUGS THAT DECREASE AQUEOUS PRODUCTION
I. Beta-Blockers [Timolol]
-Mechanism: Act on ciliary body to  production of aqueous humor
-Administration: Topical drops to avoid systemic effects
-Side Effects: Cardiovascular (bradycardia), bronchoconstriction , depression
II. Alpha-2 Adrenergic Agonists [Brimonidine]
-Mechanism:  production of aqueous humor
-Administration: Topical drops
-Side Effects: Lethargy, fatigue, dry mouth.
III. Carbonic Anhydrase Inhibitors [Acetazolamide]
-Mechanism: Blocks CAI enzyme production of bicarbonate ions (transported to
posterior chamber, carrying osmotic water flow), thus  production of
aqueous humor
-Administration: Oral, topical
-Side Effects: kidney stones, possible (rare) aplastic anemia

25. DRUGS THAT INCREASE AQUEOUS OUTFLOW
I. Nonspecific Adrenergic Agonists [epinephrine)
-Mechanism:  uveoscleral outflow of aqueous humor
-Administration: Topical drops
-Side Effects: Can precipitate acute attack in patients with narrow iris-corneal angle,
headaches, cardiovascular arrhythmia, tachycardia
II. Parasympathomimetics [Pilocarpine]
-Mechanism:  contractile force of ciliary body muscle,  outflow via TM
-Administration: Topical drops or gel.
-Side Effects: Headache, induced miopia.
III. Prostaglandins [latanoprost]
-Mechanism: May  uveoscleral outflow by relaxing ciliary body muscle
-Administration: Topical drops
-Side Effects: Iris color change

26. Generally recommended for patients with open angle glaucoma that continues
to progress despite use of medications.
During ALT (Argon laser trabeculoplasty), an Argon laser beam is directed at
the trabecular meshwork.
If the laser is successful, changes occur in the trabecular meshwork that enable
it to drain fluid more effectively.
Laser trabeculoplasty

27. Conventional surgery
Conventional surgery (filtering microsurgery) involves creating a drainage hole
with the use of a small surgical tool.
 This new opening allows the intraocular fluid to bypass the clogged drainage
canals and flow out of this new, artificial drainage canal.

28. Conventional surgery

29. Advancement-Trabectome surgery
Trabectome surgery increases the amount of fluid exiting the eye.
The tip of the Trabectome removes the strainer-like tissue (trabecular
meshwork) that reduces flow into the natural drainage system.
Studies indicate that Trabectome usually lowers the eye pressure by about
30%, while also decreasing the number of glaucoma eye drops that need to
be taken.

30. TUBE SHUNT IMPLANTATION
Tubes or glaucoma shunts are devices that are implanted in the eye and provide an
artificial alternative drainage site for fluid from the eye.
 Most shunt devices look somewhat like a computer mouse.
Usually, a small incision is made near the top of eye underneath the conjunctiva.
The tube which extends from the body of the device, is inserted into the eye's anterior
chamber.

31. TUBE SHUNT IMPLANTATION

32. REFERENCES
1. Casson, Robert J; Chidlow, Glyn; Wood, John PM; Crowston, Jonathan G; Goldberg,
Ivan (2012). "Definition of glaucoma: Clinical and experimental concepts". Clinical &
Experimental Ophthalmology 40 (4): 341–349.
2. QuigleyHA,BromanAT.(2006) “The number of people with glaucoma worldwide in
2010 and 2020”,Br J Ophthalmol;90(3):262-267.
3.George R,Ramesh S Ve,Vijaya L.(2010) “Glaucoma in India:Estimated Burden of
Disease” J Glaucoma;19:391-397.
4. Kingman, Sharon (2004). "Glaucoma is second leading cause of blindness globally".
Bulletin of the World Health Organization 82 (11): 887–888.
5. Kingman, Sharon (2004). "Glaucoma is second leading cause of blindness globally".
Bulletin of the World Health Organization 82 (11): 887–888.
6. Anderson DR.(1989), “Glaucoma: the damage caused by pressure”. XLVI Edward
Jackson Memorial Lecture. Am J Ophthalmol;108:485–495.

33. REFERENCES
7. Smith G, Atchison DA,(1997): The Eye and Visual Optical Instruments. Cambridge:
Cambridge University Press 46(10):15-45.
8. Andrew Iwach, MD (GREG): Trabeculectomy with Intraoperative Sponge 5-Flourouracil.
Ophthalmology 1996 Jun;103(6):963-970.
9. http://eyewiki.aao.org/Medical_Management_for_Primary_Open_Angle_Glaucoma
10. Schwartz K, Budenz D,(2004): Current management of glaucoma. Curr Opin
Ophthalmol 15:119-140.

34.  Sincere thanks to Dr. Debojyoti Chakrabarty, the Head of the P.G. Dept. of
Zoology, Barasat Govt. College for his valuable suggestions and providing
infrastructure facilities.
Thanks to Dr. Tuhin Kumar Saha, Dr. Madhumita Manna,
Dr. Debjani Sarkar, Dr. Sanjay Podder, Dr. Srikanta Guria, Dr.Tanaya Dey for
providing encouragements and various help during the entire period of study.
Thanks to my seniors of SEM-III.
Grateful thanks also to the non teaching stuffs of our department
Lastly, the co-operation received from the classmates is also acknowledged.
ACKNOWLEDGEMENT

35. THANK YOU