Open Angle Gluacoma

Question 1

What is glaucoma?

Answer 1

Optic nerve damage caused by a rise in intraocular pressure

Question 2

What causes raised intraocular pressure?

Answer 2

A blockage in the aqueous humour trying to escape the eye through trabecular network

Question 3

2 types of glaucoma?

Answer 3

Open angle and closed angle

Question 4

What contains the vitreous humour?

Answer 4

Vitreous chamber

Question 5

What chambers are filled with aqueous humour?

Answer 5

Anterior and posterior chamber

Question 6

Where is the anterior chamber?

Answer 6

Between cornea and iris

Question 7

What is between the lens and the iris?

Answer 7

Posterior chamber

Question 8

What produces the Aqueous humour?

Answer 8

Ciliary body

Question 9

Journey of the aqueous humour?

Answer 9

Flows around iris to anterior chamber where it drains through the trabecular meshwork and into canal of schlemm. From there it enters general circulation

Question 10

Normal intraocular pressure?

Answer 10

10-21mmHg

Question 11

Pathophysiology of glaucoma?

Answer 11

The gradual increase in resistance through trabecular meshwork makes it more difficult for the Aqueous humour to flow through the meshwork and exit the eye

Question 12

What does gradual increase in resistance through trabecular meshwork result in?

Answer 12

The pressure slowly builds within the eye and this gives slow and chronic onset of glaucoma

Question 13

What does increased intraocular pressure cause?

Answer 13

Cupping of optic disc

Question 14

What is in the centre of a normal optic disc and what happens to it when there is raised ICP?

Answer 14

Optic cup (Small indent in optic disc)
Raised ICP pressure causes cup to become bigger (cupping)

Question 15

Risk factors for Glaucoma?

Answer 15

Increasing age
Family history
Black ethnic origin
Near sightedness (myopia)

Question 16

What is myopia?

Answer 16

Near sightedness

Question 17

Presentation of open angle glaucoma?

Answer 17

Asymptomatic for long time

• Glaucoma affects peripheral vision first (Tunnel vision)
• Gradual onset of fluctuating pain
• Blurred vision
• Halos around light

Question 18

Types of Investigation for open angle glaucoma?

Answer 18

Non-contact tonometry
Goldmann Applanation tonometry
Fundoscopy
Visual field assessment

Question 19

Gold standard investigation for open angle glaucoma?

Answer 19

Goldmann Applanation Tonometry

Question 20

What is non-contact tonometry?

Answer 20

-Commonly used for estimating intraocular pressure
-Shoots a puff of air at cornea and measures corneal response to it
Less accurate but helpful for general screening

Question 21

What is Goldmann Applanation Tonometry?

Answer 21

Way to measure intraocular pressure

• Involves special device mounted on slip lamp that makes contact with the cornea & applies different pressures to front of cornea
• Accurate

Question 22

Diagnosis of OAG?

Answer 22

• Goldmann applanation Tonometry (Intraocular pressure)
• Fundoscopy (Optic nerve health)
• Visual Field assessment (check peripheral vision loss)

Question 23

Aims of management for OAG?

Answer 23

Reduce intraocular pressure

Question 24

1st line Management of OAG?

Answer 24

Prostaglandin analogue eyedrops (latanoprost)

Question 25

Other options of management for OAG?

Answer 25

-Beta blockers (Timolol)
Carbonic anhydrase Inhibitors (Topical Dorzolamide)
Sympathomimetics (brimonidine)
Trabeculectomy surgery (If all else ineffective)

Question 26

Side effects of Latanoprost?

Answer 26

Eyelash growth
Eyelid pigmentation
Iris pigmentation

Question 27

Causes of glaucoma?

Answer 27

Old age
Myopia
Diabetes

Question 28

Symptoms of chronic open angle glaucoma?

Answer 28

Loss of peripheral vision

Question 29

Diagnosis of open angle glaucoma?

Answer 29

• Tonometry
• Central corneal thickness
• Gonioscopy

Question 30

Clinical signs of open angled-glaucoma?

Answer 30

• Cupping
• Visual filed defect= damage on bottom half of disc=damage to top half of vision
• May or may not have high IOP