Flashcards in Clinical (1 - 4) Deck (119):
What can fluorescein eye drops do?
Identify areas of epithelial loss
What is a blow out fracture?
Fracture of the inferior orbit
What muscle can be trapped in a blow out fracture and how does this present?
-> Eye can't be elevated
Even though the medial orbital wall is thinner, why is it less likely to fracture?
Ethmoidal air cells provide some degree of protection
What type of haemorrhage can result from a blow out fracture?
What is a hyphaema?
Blood in the anterior chamber
What is the potential sequelae of hyphaema?
Blood can block the trabecular meshwork:
-> Increased IOP due to no aqueous drainage
How does a dis-inserted iris appear?
Poor border between iris and cornea
What is visible in a dislocated lens?
What conditions can cause a lens dislocated and what direction does the lens move in each?
- Upwards and outwards
- Downwards and inwards
How does a retinal detachment appear on fundoscopy?
Blood vessels aren't continuous
How do the blood vessels appear in a choroidal tear?
What is the name for a bruised retina?
What are some signs of a corneal laceration?
- Apply a fluorescein strip
- Turns pale due to aqeuous leakage
How is a sub-tarsal foreign body treated?
Particle is removed
Chloramphenicol is applied
What can cause a intra-lenticular foreign body (IOFB) (ie. within the lens)?
Fast moving particles (hammer and chisel injuries)
What investigation must be done in a suspected intra-lenticular foreign body?
X-ray -> Water's view
Which of the following is not a typical sign of a small foreign body in the eye:
- Irregular pupil
- Shallow anterior chamber
- Localised cataract
- Gross inflammation
What types of chemical burn has easy and rapid penetration; alkali or acid?
How does an alkali burn affect the eye?
1. Cicatrising changes to conjunctiva and cornea
2. Scar formation
3. Limbal ischaemia -> China White sign
What effect does an acid burn have on the eye?
When dealing with an ocular chemical burn, what two chemicals must we be weary of?
What two tests must be done in an ocular chemical burn?
How do we treat an ocular chemical burn initially?
- Minimum 2L saline
- OR until pH is normal
Which of these is not a cardinal feature of neuro-ophthalmic disease:
- Reduced visual acuity
- Uncomfortable eye movements
- Visual field loss
Uncomfortable eye movements
What is the leading cause of neuro-ophthalmic disease?
What type of tumours (primary and secondary) tend to cause neuro-ophthalmic disease?
Space-Occupying lesions (SOL)
What other causes of neuro-ophthalmic disease are there?
Demyelination -> MS
What features can help indicate the cause of neuro-ophthalmic disease?
Site of lesion
What imaging modality is important in neuro-ophthalmic disease?
What can cause a CN VI palsy?
Increased ICP -> Papilloedema
What are the clinical features of a bilateral CN IV palsy?
Due to blunt head trauma
A patient presents with an acutely painful left eye. They have had a headache for about an hour and have noticed double vision for just as long. On examination the eye is protruding and the pupil is dilated. The patient cannot elevate or adduct their eye.
Anuerysm of posterior communicating artery resulting in CN III palsy
Which of the following is not a typical cause of CN III palsy:
When we look left, both eyes should look in the same direction, at the same time, at the same speed. What pathways allow this and what condition can affect this?
What is the optic pathway comprised of?
1. Optic nerve
2. Optic chiasm
3. Optic tracts
4. Optic radiations
What tumours can cause optic neuropathy?
What conditions typically causes optic neuritis?
In optic neuritis, when is the pain exaggerated?
Which of the following is not a sign/symptom of optic neuritis:
- Colour desaturation
- Central scotoma
- Pain behind eye
- Double vision
- Unilateral, progressive visual loss
What is central scotoma?
Central loss of vision
Which of the following is optic neuritis not associated with:
- Drugs (Ethambutol -> Bilateral)
How long does optic neuritis take to recover?
Weeks to months
What sort of visual loss do optic nerve defects present with (typically)?
Abiding the horizontal
What tumours can affect the optic chiasm?
What field defect is typical of an optic chiasm pathology?
Bitemporal visual loss
What pathologies can affected the optic tracts and radiations?
Primary and secondary tumours
What visual defects are seen in optic tract and optic radiation pathologies?
Homonymous (on same side)
Macula not spared
Quadrantanopia (If optic radiation)
What visual defects are seen in occipital cortex pathologies?
Which of these is not a cause of sudden visual loss:
- Vascular aetiology
- Retinal detachment
- ARMD (wet type)
- Open angle glaucoma
- Optic neuritis
Open angle glaucoma:
- Closed angle glaucoma -> Sudden visual loss
Occlusion of what vascular structures can cause sudden visual loss?
Optic nerve head circulation
Haemorrhage from what vascular structures can cause sudden visual loss?
Abnormal blood vessels (DM + wet ARMD)
Which of the following is not a risk factor for CRAO and CRVO:
- High cholesterol
- Increased IOP (only in CRVO)
A patient presents with sudden onset, painless visual loss. It is unilateral and the visual loss is profound. On examination, the swinging light test shows a relative afferent pupillary defect and there is a pale, oedamtous retina.
Central retinal artery occlusion (CRAO)
What can cause a CRAO?
Carotid artery disease
Emboli from heart (unusual)
How do we manage a CRAO and when would these treatments be appropriate
- Ocular massage (if within 24 hours)
- Aims to turn CRAO into BRAO
- Establish embolus source -> Carotid doppler
- Assess/Manage risk factors
A patient presents with a painless loss of vision. They described it like 'a curtain coming down'. They said it recovered after around 5 minutes. On examination of the fundus there are no abnormalitis
Amaurosis Fuga (Transient CRAO)
How is a transiet CRAO treated?
Referral to TIA clinic
How would a migrainous transient visual loss present?
Visual loss followed by headache
What is Virchow's Triad and what can it cause?
How does increased IOP cause a CRVO?
What would you expect to see on fundoscopy in a CRVO patient?
DIlated, tortuous vessels
Disc and macular swelling:
How do we manage a CRVO?
Treat systemic/ocular causes:
How do we prevent a vitreous haemorrhage?
Laser treatment of new vessels
What is a medical treatment that is directed at preventin new vessel formation in CRVO?
Occlusion of what artery causes Ischaemic Optic Neuropathy?
Posterior ciliary artery
What fudoscopy signs point towards an ischaemic optic neuropathy?
What are the two types of ischaemic optic neuropathy and what causes them?
- Inflammation (GCA) (50%)
- Athersclerosis (50%)
What vessels are inflammed in GCA?
Medium to large sized arteries:
- Giant multinucleated cells invade tissues
What are the visual symptoms of GCA?
Profound -> Counting fingers (CF) - No perception of light
What investigations are important in GCA?
Very high CRP, PV, ESR
Temporal artery biopsy
Where does haemorrhage typically happen in the eye in terms of sudden visual loss?
What vessels can vitreal haemorrhage occur from?
- Retinal ischaemia and angiogenesis
- CRVO and DM
- Retinal tear
Which of the following is not a sign/symptoms of vitreous haemorrhage:
- Loss of vision
- Loss of red reflex
- Haemorrhage on ophthalmosopy
If a vitreous haemorrhage doesn't resolve, how is it treated?
A patient presents with a painless loss of vision in their left eye. They noticed a very sudden onset of floaters. On ophthalmoscopy there is clear ballooning of the retina and vessels don't seem to join up.
What else might be seen on examination and fundoscopy of a retinal detachment (apart from ballooning and vessels not being continuous)?
What is the commonest cause of blindness in the western world in patients over 65?
Age Related Macular Degeneration
What are the two types of ARMD and what vision loss do they cause?
Dry -> Gradual loss
Wet -> Sudden loss
What is the pathology of wet ARMD?
1. New blood vessels grow under retina
2. New vessels leak
3. Build up of fluid/blood
Where is the visual loss in wet ARMD, central or peripheral?
What is metamorphopsia>
Distortion of vision (ARMD)
What were the older treatments for wet ARMD?
What is the newer treatment for wet ARMD?
Antio-VEGF into vitreous cavity
What is the typical pattern of gradual vision loss?
In terms of gradual visual loss, what does the acronym CARDIGAN stand for?
ARMD (dry type)
Inherited diseases -> Retinitis Pigmentosa
Access -> To eye clinical
What is a cataract?
What congenital causes are there of cataract?
Describe the characteristics of the following kinds of cataract:
- Posterior subcapsular
- Involving central part of lens
- Cloudy at back of lens
- aka 'Christmas Tree Cataract'
When do we manage a cataract?
How do we treat a cataract?
Surgical removal and intra-ocular lens replacement
How does dry ARMD appear on fundoscopy?
- Build up of waste below RPE
Atrophic patches of retina
What is myopia?
What is hypermetropia?
What causes astigmatism?
Irregular corneal curvature
What is presbyopia?
Loss of accommodation with age
What is glaucoma?
Progressive optic neuropathy
A patient present with a painful red eye and visual loss. They are complaining of headache and vomiting before presenting.
How is angle-closure glaucoma treated?
Reduce IOP with drops/PO drugs
Cupped disc and an arcuate visual field defect are often signs of what?
What is the treatment for open-angle glaucoma?
Preserve vision by reducing IOP:
- Eye drops
What is the commonest cause of diplopia?
- eg. Reduced CN VI blood supply -> LR paralysis
Which of the following is not a risk factor for diplopia:
How can diplopia be controlled?
Temporary prism lense
What does RAPD suggest?
Affected eye is less sensitive to light
What are retinal causes of RAPD?
Which of the following is not an optic nerve cause of RAPD?
- Optic neuritis
- Ischaemic Optic Neuropathy
- Pituitary tumour
- Optic nerve compression
What does 'swollen optic discs' mean?
Disc swelling secondary to ANY cause
What does papilloedema mean?
Disc swelling secondary to raised ICP
If there is bilateral papilloedema what should be suspected?
Raised ICP due to a space-occupying lesion
What does CN II examination include?
Visual field assessment
What causes disc swelling in the context of raised ICP?
1. Raised ICP transmitted to CN II via subarachnoid space
2. Interruption of axoplasmic flow
3. Venous congestion
What contributes to ICP?
How can raised ICP result in cardiopulmonary arrest?
Brain is squeezed through foramen magnum
What can cause a raised ICP in terms of CSF?
Obstruction to CSF circulation
Overproduction of CSF
A 25 year old female presents with an 8 month history of headaches. On examination her BMI is 38 and her visual acuity is 6/6 in both eyes. She informs you she is also on the oral contraceptive pill.
Idiopathic Intracranial Hypertension (IIH)
What examination and investigation features are present in IHH?
Bilateral disc swelling
Increased CSF opening pressure on lumbar puncture
Which of the following is not a theory of why the discs swell in IIH:
- Stenosis of transverse cerebral sinuses
- Increased abdominal pressure
- Vitamin A
- Optic nerve head retinal occlusion
- Microemboli in sagittal sinus blocking CSF absorption
Optic nerve head retinal occlusion