The Eye in Systemic Disease

Question 1

what are the cardinal features of neuro-opthalmic disease?

Answer 1

diplopia (eye movement defects)

visual acuity/visual field loss (visual defects)

Question 2

what is normal intracranial pressure?

Answer 2

15 or less
15-20 abnormal
20 or more is pathological

Question 3

what is the Munro Kellie hypothesis?

Answer 3

volume of cranial cavity is constant (80% brain, 10% blood, 10% CSF)

Question 4

what is supranuclear control?

Answer 4

agreement between brain, eyes, limbs - muscles of the eye are at a slight angle.

Question 5

what occular motility defects most commonly occur?

Answer 5

SO intorsion/depression in adduction

LR palsy - cross eyed

Question 6

what are the causes of a CN VI palsy?

Answer 6

microvascular
raised ICP
tumour
congenital

Question 7

which condition can occur in a CN VI palsy?

Answer 7

papilloedema

Question 8

what can occur in a CN IV palsy?

Answer 8

head tilt due to weak incyclo-torsion

torsion and chin depression

Question 9

what are the causes of a CN IV palsy?

Answer 9

congenital decompensated
microvascular
tumour
bilateral - trauma

Question 10

what is the clinical sign of a CN III palsy?

Answer 10

eyes “down and out” and complete ptosis

Question 11

what are the causes of a CN III palsy?

Answer 11

Microvascular
Tumour
Aneurysm
MS
Congenital

Question 12

cause of a painful CN III palsy?

Answer 12

aneurysm (EMERGENCY)

Question 13

what is inter-nuclear opthalmoplegia?

Answer 13

most often caused by MS or cerebrovascular disease (due to dysfunction of the medial longitudinal fasiculus); when looking to the side one is normal but one tends to wobble, diplopia when looking to one side

Question 14

what are the causes of visual field defects?

Answer 14

Vascular disease - CVA
Space occupying lesion (SOL)
Demyelination (MS)
Trauma - including surgical

Question 15

what types of pathology can you get in the optic nerve?

Answer 15

Ischaemic Optic Neuropathy
Optic neuritis – commonly MS
Tumours - rare
Meningioma
Glioma
Haemangioma

Question 16

how do optic nerve defects present?

Answer 16

complete or horizontal visual defects

Question 17

what is optic neuritis?

Answer 17

inflammation of optic nerve usually due to destruction of the myelin sheath
Progressive visual loss (unilateral)
Pain behind eye, especially on movement
Colour desaturation
Central scotoma
Gradual recovery over weeks - months

Question 18

what pathology can occur in the optic chiasm?

Answer 18

Pituitary tumour
Craniopharyngioma (congenital tumour)
Meningioma
macroadenomas can press on optic chiasm (bitemporal hemianopia - pituitary)

Question 19

pathology of the optic tract?

Answer 19

tumours
demyelination
vascular anomalies
Homonomous defect (unilateral): Macula not spared; Quadrantanopia; Incongruous

Question 20

pathology of occipital cortex?

Answer 20

CVA (stroke)
demyelination
Homonomous defect, sparing the macula, congruous

Question 21

what is the pathogenesis of diabetic retinopathy?

Answer 21

chronic hyperglycaemia
glycosylation of protein/basement membrane
loss of pericytes –> microaneurysm –> leakage or ischaemia

Question 22

signs of non-proliferative retinopathy?

Answer 22

microaneurysms / dot + blot haemorrhages
hard exudate
cotton wool patches
abnormalities of venous calibre
Intra-retinal microvascular abnormailities (IRMA)

Question 23

where do new vessels grow in diabetic retinopathy?

Answer 23

grow on disc (NVD)
grow in the periphery (NVE)
grow on iris if ischaemia is severe

Question 24

how do diabetics lose vision?

Answer 24

retinal oedema affecting the fovea
vitreous haemorrhage
scarring/ tractional retinal detachment

Question 25

how is retinopathy classified?

Answer 25

no retinopathy non-proliferative retinopathy (mild/moderate/severe) proliferative retinopathy

Question 26

how is maculopathy classified?

Answer 26

No maculopathy observable maculopathy referable maculopathy clinically significant maculopathy

Question 27

how do we manage maculopathy/retinopathy in diabetics?

Answer 27

optimise medical mangement laser treatment (PRP or macular grid) surgery -vitrectomy rehabilitation if blind/partially sighted

Question 28

how does hypertensive retinopathy occur?

Answer 28

Appearance of fundus correlates to severity of hypertension and the state of the retinal arterioles young people can have extensive retinopathy elderly patients with arteriosclerotic vessels often have minimal changes

Question 29

features of hypertensive retinopathy?

Answer 29

``` Attenuated blood vessels-copper or silver wiring cotton wool spots hard exudates retinal haemorrhage optic disc oedema ```

Question 30

what is accelerated hypertension?

Answer 30

often in younger patients; dramatic appearance of the fundus can have decreased vision

Question 31

what is the pathogenesis of central retinal artery occlusion?

Answer 31

Sudden painless loss of vision very profound loss of vision retinal nerve fibre layer becomes swollen except at fovea (cherry red spot) rarely recovers

Question 32

what is the pathogenesis of central retinal vein occlusion?

Answer 32

Sudden painless visual loss range of visual loss need to determine degree of ischaemia Ischaemia correlates to degree of reduced vision and fundal appearances (rubeotic eye)

Question 33

what is branch vein occlusion?

Answer 33

Painless disturbance in vision may be assymptomatic may be aware of loss of part of field

Question 34

which inflammatory diseases can affect the eye? (causes of uveitis)

Answer 34

``` INFECTIVE: TB Herpes Zoster Toxoplasmosis Candidiasis Syphilis Lyme Disease ``` ``` NON-INFECTIVE: Idiopathic Syndromes HLA-B27 SLE Juvenile Arthritis Sarcoidosis Behcet’s Disease Crohn's/UC/Coeliac ```

Question 35

what is giant cell arteritis?

Answer 35

``` Inflammation of middle sized arteries associated with polymyalgia rheumatica Headache jaw claudication Malaise Raised P.V. Blinding Condition ```

Question 36

what are the extraoccular features of thyroid eye disease?

Answer 36

``` Proptosis Lid signs: retraction oedema lag pigmentation Restrictive myopathy ```

Question 37

what are the occular signs of thyroid eye disease?

Answer 37

``` Anterior Segment: chemosis injection exposure glaucoma Posterior Segment: choroidal folds optic nerve swelling ```

Question 38

how does thyroid eye disease occur?

Answer 38

Characterised by swelling of the extraocular muscles and orbital fat Autoimmune Most common cause of unilateral and bilateral proptosis Spectrum of severity Potential blinding complications

Question 39

how is thyroid eye disease treated?

Answer 39

control of thyroid dysfunction (usually hyperthyroid/Grave's) lubricants e.g. saline drops surgical decompression if severe

Question 40

what is SLE and how does it cause eye disease?

Answer 40

multisystem immunological disease (autoimmune) | anti-DNA Antibody causes occular inflammation

Question 41

how does Rheumatoid Arthritis cause eye disease?

Answer 41

autoimmunity Dry eyes (Keratoconjunctivitis Sicca) Scleritis Corneal melt

Question 42

what is Sjogren's syndrome and how does it cause eye disease?

Answer 42

``` Triad: -keratoconjunctivitis sicca -xerostomia -Rheumatoid Arthritis (usually) infiltration of lacrimal glands ```

Question 43

what is Marfan's syndrome and what eye disease does it cause?

Answer 43

familial connective tissue disease due to abnormal folding of the fibrillin-1 protein causing long limbs, high arched palate, affecting cardiac valves and aorta eye disease - lens dislocation due to weakness in cilliary zonules (causes near-sightedness and blurred vision), can also have increased risk of retinal detachment, cateracts and glaucoma

Question 44

which dermatological conditions can affect the eye?

Answer 44

``` Stevens-Johnson syndrome (Symblepharon, occlusion of lacrimal glands, corneal ulcers) it is a reaction to drugs erythema multiforme drug or food sensitivity maculopapular rash stomatitis conjunctivitis ```