Papilloedema Flashcards
What is the definition of papilloedema?
Optic disc swelling secondary to raised intracranial pressure
All patients with bilateral optic disc swelling should be suspected of having what, until proven otherwise?
Raised ICP due to a space occupying lesion
What examination/investigation is necessary to detect bilateral optic disc swelling?
Ophthalmoscopy
The subarachnoid space around the optic nerve is continuous with what?
The subarachnoid space around the brain
When ICP increases, this is transmitted onto where, causing papilloedema?
Optic nerve
As a result of increased pressure, what actually causes the swollen discs of papilloedema?
Interruption of axoplasmic flow (organelles getting to and from neurones) and venous congestion
Intra-cranial pressure is the sum of what 3 components?
Brain, blood, CSF
What happens to the brain when ICP rises? What effect does this have on the patient?
It is squeezed through the foramen magnum which results in compression of the brainstem, so the patient cannot breathe and dies
Most of the CSF is produced where?
Lateral ventricles by the choroid plexuses
Where does CSF travel once it has been produced?
Through the 3rd and 4th ventricles and into the subarachnoid space
In what 3 situations would ICP increase?
Obstruction to CSF circulation, overproduction of CSF, inadequate absorption
What vital sign is really important to check when a patient has disc swelling?
BP
What can be a cause of optic disc swelling, particularly in obese patients?
Idiopathic intracranial hypertension
What happens if there is chronic optic disc swelling?
The swelling subsides, but the disc becomes atrophic and pale. Loss of visual function occurs and blindness may result.
Ophthalmoscopy is part of the examination of which nerve? What else is done to test this nerve?
CNII- visual fields, visual acuity, pupil exam, colour vision
