Pathology Flashcards
Which tumours can affect the ventricles and choroid plexus
Colloid cyst - often at interventricular foramen
Ependymomas - arise from ependymal cells
Choroid plexus tumours
What is hydrocephalus
Accumulation of CSF in the brain
Usually due to some sort of blockage in the system
Can cause the head to enlarge and increases pressure in brain
Treated with a shunt
List the different types of ventricular haemorrhage
Epidural hematoma, arterial bleed between skull and dura
Subdural hematoma, venous bleed between dura and arachnoid
Subarachnoid haemorrhage
What is idiopathic intracranial hypertension
Increase in CSF pressure but no imaging features of hydrocephalus
No known cause
Causes headache and visual disturbance
What is papilloedema
Optic disc swelling due to raised intracranial pressure - puts pressure on the optic nerve
Causes enlarged blind spot, blurred vision and loss of vision
Graded from 1-5
What can cause raised intracranial pressure
Head injury
Space occupying lesion, tumour, abscess or haemorrhage
Hydrocephalus
Meningitis - leads to inflammation
What occurs if raised ICP is not relieved
Brain damage
What visual changes can occur with raised ICP
Transient blurry vision Double vision - diplopia Loss of vision Papilloedema Pupillary changes
Can affect one or both eyes depending on cause
How can raised ICP affect the optic nerve
Compresses them
Will also compress the blood supply to the retina
Leading to swelling off the optic disc - papilloedema
What visual symptoms occur with papilloedema
Transient visual obscurations Transient flickering Blurring Constriction of the visual field Decreased colour perception
Describe the appearance of the optic disc in papilloedema grade 1-5
Blurry margins in all grades 1 - C shaped halo 2 - circular halo 3 - peripheral vessels disappear from view 4 - central vessels disappear 5- no visible vessels
What can damage the oculomotor nerve
Compression by raised ICP
Tentorial herniation - pushed through notch by raised ICP
Which fibres tend to be affected first when the oculomotor nerve is compressed
Parasympathetic
They usually sit on the outside of the nerve
List symptoms of oculomotor nerve damage
Paralysis of extra-ocular muscles
No/slow pupillary reflex (parasympathetic not working)
Dilated pupil - when it becomes fixed it means there has been severe damaged
Ptosis - damage of nerve to LPS
Eye looking down and out - superior oblique still works
Describe symptoms of trochlear nerve damage
Paralysis of superior oblique muscle - cannot move inferomedially
Diplopia when looking down
What is diplopia
Double vision
What can damage the trochlear nerve
Stretching
Compression - ICP
isolated injury is very unusual
What type of damage is the abducent nerve susceptible to
Stretch
What are the symptoms of abducent nerve damage
Eye can’t move laterally in horizontal plane - lateral rectus is paralysed
Medial deviation of eye
What are cataracts
Opacification within the lens
Leads to reduction in vision which affects daily living
What can cause cataracts
Degenerative changes in lens fibres - age (most common)
Cumulative UVB damage
May also be caused by hypertension, smoking
Trauma - can be a sudden cataract
Metabolic - diabetes
Congenital
Drug induced - steroids
Intra-uterine infections - rubella, CMV, toxoplasmosis
What is glaucoma
A group of diseases characterised by progressive optic nerve damage and visual field loss
Abnormal increase in pressure in the eye
Due to the amount of vitreous fluid and aqueous humour
What areas of the eye does glaucoma have the biggest consequences
Optic disc and nerve
What causes 50% of blindness worldwide
Cataracts
rarely causes blindness in UK but is the most common cause of gradual visual impairment,