Pathology

Question 1

Describe the histology of the lens

Answer 1

Largely enucleate with cells that elongate to produce fires

Question 2

What is the main pathology of the lens?

Answer 2

Cataracts

Question 3

What are cataracts?

Answer 3

Opacification’s within the lens (50% of all causes of blindness worldwide)

Question 4

In the UK what is the main cause of cataracts?

Answer 4

Age

Question 5

How do cataracts occur due to ageing?

Answer 5

As the lens epithelium matures eventually the cell contents are replaced and the nucleus disappears leaving a fibre within the lens. Alteration in reparative mechanism means that with age the fibres get stuck in a cross linked structure.

Question 6

What increases the likelihood of cataracts?

Answer 6

Cumulative UVB damage

Question 7

Other than age name some cases of cataracts

Answer 7

Hypertension, smoking, post-op, trauma, metabolic disease, genetics, diabetes

Question 8

How does diabetes cause cataracts?

Answer 8

Changes to osmotic pressures alter the fluid content and damage fibres

Question 9

What is glaucoma?

Answer 9

Abnormal increase in pressure in the eye due to a blockage in the drainage system

Question 10

What does the increased pressure relate to?

Answer 10

Vitreous fluid and aqueous humour

Question 11

Describe the physiological drainage of fluid

Answer 11

Through the trabecular meshwork and out schlemm’s canal

Question 12

Where does glaucoma have the biggest impact?

Answer 12

Optic nerve and disc

Question 13

Name two types of glaucoma

Answer 13

Open angled

Angle closure

Question 14

Describe the presentation and cause of open angled glaucoma

Answer 14

Due to poor drainage through the meshwork

Presents with slow onset often asymptomatic

Question 15

What does treatment of glaucoma involve and aim to do?

Answer 15

Aims to slow down the disease by drugs that widen the canal

Question 16

Describe the presentation and cause of angle closure glaucoma

Answer 16

Drainage is patent but the fluid cannot reach it as the lens is in contact with the iris.
Emergency - patient will be acutely unwell, red eye, visual loss and headache with nausea and vomiting

Question 17

How is angle closure glaucoma treated?

Answer 17

Laser surgery

Question 18

How can raised ICP present in the disc?

Answer 18

Cupping - rolled edges and a depressed centre

Question 19

Define papilloedema

Answer 19

Swelling of the optic nerve/disc due to increased ICP

Question 20

What are scleritis/episcleritis?

Answer 20

Inflammation of the sclera

Question 21

Describe scleritis

Answer 21

Rare but severe, associated with pain on movement and may have an underlying autoimmune aetiology

Question 22

What autoimmune diseases are associated with scleritis?

Answer 22

SLE, HLA B27 conditions

Question 23

Describe episcleritis

Answer 23

Superficial and self limiting with no clear cause

Question 24

What does ARMD stand for?

Answer 24

Age related macular degeneration

Question 25

What two types is ARMD divided into?

Answer 25

Dry - no significant vascular proliferation | Wet - vascular proliferation

Question 26

Describe dry ARMD

Answer 26

Accumulation of drusen which may become calcified presents with reduced acuity, partial visual loss or distorted vision

Question 27

Describe wet ARMD

Answer 27

Neovascularisation in choroid mediated by VEGF - new vessels are fragile and leaky which leads to haemorrhage and visual loss

Question 28

How can wet ARMD be treated?

Answer 28

Monoclonal antibodies to VEGF

Question 29

What can sometime be visible when looking at the eye in ARMD?

Answer 29

Grey membrane

Question 30

Name two changes that can occur in diabetics in the pupils

Answer 30

``` Argyll Roberson (accommodate but don't react) Peripheral Neuropathy ```

Question 31

Why do diabetics get cataracts?

Answer 31

Increased sugar in the lens, glucose is converted to sorbitol and this altered gradient leads to swelling and fire disruption

Question 32

What type of glaucoma is a rare late presentation in diabetics?

Answer 32

Rubeotic glaucoma - new vessel formation obstructs angle

Question 33

Describe retinopathy

Answer 33

Complex mechanisms lead to poor functioning vessels which are leaky causing aneurysms

Question 34

What happens in severe retinopathy?

Answer 34

New vessels form

Question 35

What is maculopathy?

Answer 35

Damage to the retina as a result of retinopathy causes oedema and ischaemia which can lead to visual loss

Question 36

When looking at the eye what might signify a patient has had laser surgery?

Answer 36

Lots of well demarcated light dots

Question 37

Name two types of occlusion disease

Answer 37

Central retinal artery occlusion | Central retinal vein occlusion

Question 38

What tumours can present in the eye?

Answer 38

BCC, SCC, Melanoma

Question 39

In terms of tumours what must you be careful of in the eye?

Answer 39

Retinal melanoma may look like a mole | Beware of metastatic disease