Week 1.11 Diabetes

Question 1

Type 1 diabetes

Answer 1

Needs complete insulin replacement
Can occur many age normally young non obese (under 30)

Question 2

What does IDDM mean

Answer 2

Insulin dependent diabetes

Question 3

What is insulin pump

Answer 3

monitors the blood glucose and pumps the correct amount of insulin that the body needs

Question 4

Type 2 diabetes

Answer 4

Older px
Obese and non obese
Insulin still produced - not enough for body’s needs or body can’t utilise it well enough
Mainly drug or diet controlled

Question 5

Symptoms of type 2

Answer 5

Increased thirst
Urination
Slow healing cuts
Itching skin infections
Tired
Blurred vision
Constant hunger
Unexplained weight loss

Question 6

What are some non retinal diabetic ocular changes

Answer 6

Refractive changes - px reports glasses working well line week and not the next
Corneal changes - may not heal easily - cls complication
Cataract can develop earlier
Glaucoma
Cranial nerve palsy - may develop double vision
Vitreous opacity - bleed in vitreous
Infections

Question 7

Diabetic retinopathy

Answer 7

• Diabetic retinopathy present in 1/3rd of all those with diabetes
• Leading cause of blindness in <60s
• Maculopathy is the leading cause of blindness
• 20 years from onset at least 60% of those with type 2 will have retinopathy
• The longer u have diabetes the greater the risk so if u have type 1 diabetes u have a high chance of getting diabetic retinopathy

Question 8

Duration of diabetes

Answer 8

o If diagnosed before age of 30
 50% will have DR after 10 years
 90% will have DR after 30 years
o DR rarely develops within 5 years of onset or before puberty
 However, 5% type 2 diabetics have DR on presentation

Question 9

Risk factor for diabetic retinopathy

Answer 9

• duration
• poor metabolic control
• pregnancy
• hypertension
• nephropathy
• smoking, obesity, hyperlipidemia

Question 10

What is micropangiopathy

Answer 10

disease of very small blood vessels ultimately caused by excess sugar in blood which leads to problems resulting from occlusion of blood vessels and problems as a consequence of leakage from blood vessels

Question 11

What is the different types of DR

Answer 11

• Background – minimal/mild non-proliferative
  o Intraretinal
• Pre-proliferative – moderate/severe non-proliferative
  o Proliferative disease imminent
• Proliferative
  o Onto/beyond retinal surface
• Maculopathy
  o Involvement of fovea (can occur even if other retinal signs are relatively mild)

Question 12

What is the percentage of BDR?

Answer 12

If diabetic for more than 20 years 80% chance

Question 13

Haematological changes

Answer 13

Decrease in o2 transport
Red blood cells - deformed, increased rouleaux formation (stacking up like coins)
Platelets - increased stickiness, increased aggregation

Question 14

What is signs of minimal non-proliferative diabetic retinopathy

Answer 14

Microaneurysms

Question 15

What are symptoms of mild non proliferative diabetic retinopathy

Answer 15

Microaneurysms and one of:
- hard exudates
- cotton wool patches
- intraretinal haemorrhages
* dot and blot
* flame shaped haemorrhages

With no characteristics of MODERATE retinopathy

Question 16

Circinate hard exudates

Answer 16

Circinate = forming in circular pattern. Often indicative of microaneurysms in centre which is leaking

Question 17

What are cotton wool patches

Answer 17

White fluffed superficial lesions

Death of tissues within retinal nerve fibre layer caused by reduction/blockage of flow within capillary

Leads to:
- axoplasmic statis
- swelling of neural tissue next to occlusion

Question 18

When do haemorrhages occur

Answer 18

When microaneurysms rupture

Question 19

Moderate/severe non - proliferative - pre prolif

Answer 19

Precedes proliferative diabetic retinopathy
Retinal iscaemia - deficiency of blood supply to area relative to needs
Underlying retinal capillary closure
Risk of progression to PDR - 5yr possibility
5% for low risk individuals
38% for high risk individuals

Question 20

Signs of pre proliferative retinopathy

Answer 20

Greater number of mild signs - in all quadrants
- haemorrhages
- microaneurysms
- cotton wool spots
- exudates

Intraretinal microvascular abnormalities (IrMA)
Venous changes (beading/looping)
Dark blot haemorrhages

Question 21

What is IrMA

Answer 21

Intraretinal microvascular abnormalities
- resembles new vessel growth
- Completely within retina
- don’t leak profusely on FA - if does leak then that’s proliferative
- do not cross over major retinal blood vessels

Question 22

What’s venous changes look like

Answer 22

Dilation of blood vessels
Beading
Looping
Sausage like

Question 23

How many diabetics does proliferative affect

Answer 23

5-10% of diabetics

Question 24

What does NVD and NVE stand for

Answer 24

NVD = new vessels on disc or within 1 disc diameter of disc
NVE = new vessels elsewhere along course of major vessel

Question 25

Vasoproliferative substances

Answer 25

Molecules that promote the growth of new blood vessels Vascular endothelial growth factor (VEGF) - causes angiogenesis (growth of blood vessels) Insulin-like growth factor - increased concentrations in puberty and pregnancy where diabetic retinopathy accelerates

Question 26

What is subhyaloid space

Answer 26

Between posterior vitreous and retina or under internal limiting membrane Can get a pre retinal haemorrhage in this space and just looks boat shaped and like its bleeding Sign of proliferative retinopathy

Question 27

Diabaetic maculopathy

Answer 27

Most common cause of reduced vision in diabetes 9% of diabetics Diabetes duration dependent Pregnancy hypertension poor glycemic control renal disease hyperlipaemia

Question 28

What are some things you might see in diabetic maculopathy

Answer 28

- diabetic macular oedema - increased permeability of retinal vessels - need binocular view - amsler chart distortion Focal exudatives - leakage from capillaries and microaneurysms Diffuse exudative - deep leakage from Choroidal vessels (through RPE) . Diffuse retinal thickening (diffuse oedema)

Question 29

What are symptoms of ischemic maculopathy

Answer 29

Decrease va Relatively normal looking fovea Vascular occlusions Capillary shutdown

Question 30

What might u see on OCT scan of diabetic macular oedema

Answer 30

RPE intact but macula lifted and fluid accumulated Diffuse retinal thickening

Question 31

What are the refractive changes with diabetes

Answer 31

Increase in myopia with increasing hyperglycaemia Increase in hyperopia with commencement of therapy Permanent shift - myopic shift due to increase in thickness and curvature of lens

Question 32

Corneal changes

Answer 32

Epithelium - decrease in number of cells, changes to basement membrane affecting epithelial adhesion Slower healing

Question 33

What is a classical diabetic cataract look like

Answer 33

Snowflake cataract May resolve spontaneously May mature within few days Surgery is greater risk to infections and also more likely to progress any retinopathy

Question 34

How is there a greater risk of glaucoma in diabetics

Answer 34

POAG - 2-3x greater risk Metabolic changes in trabecular mesh work NVG - new vessels grow on iris and in angle of anterior chamber

Question 35

What are some treatments of diabetic retinopathy

Answer 35

1. Retinal Photocoagulation 2. Laser Photocoagulation 3. Macular laser therapy 4. Pan retinal laser therapy 5. Vitrectomy 6. Anti VEGF

Question 36

What is the purpose of retinal photocuagulation

Answer 36

Laser burns - destroys areas of the retina where the growth factor may have been promoting the development of new vessels

Question 37

Macular laser therapy

Answer 37

Principle effect - to reduce rate of visual loss Stabilisation of vision, not visual improvement