Hydrocephalus Flashcards
def
enlargement of cerebral ventricular system
how can hydrocephalus be divided
obstructive (non-communicating)
non-obstructive (communicating)
aetiology
abnormal accumulation of CSF in the ventricles
what are the two mechanisms by which there is abnormal accumulation of CSF in the ventricles
1 impaired outflow of CSF from the ventricular system (obstructive)
-3rd or 4th ventricle lesions
-posterior fossa lesions (tumour/blood) which compress 4th ventricle
2 impaired CSF resorption in the subarachnoid villi (non-obstructive)
-tumours
-meningitis (TB)
what is normal pressure hydrocephalus
idiopathic chronic ventricular enlargement
epi
common in children + elderly
what are common causes of hydrocephalus in children
congenital malformations + tumours
what are common causes of hydrocephalus in elderly
tumours + strokes
history of obstructive hydrocephalus
rapidly decreased consciousness
double vision
history of normal pressure hydrocephalus
chronic cognitive decline
falls (due to gait apraxia)
examination of obstructive hydrocephalus
impaired GCS
papilloedema
VI nerve palsy (inability to abduct the eye)
examination of normal pressure hydrocephalus
cognitive impairment
levodopa-unresponsive gait apraxia (inability to walk in standing postition however able to make walking movements while lying) (shuffling gait)
hyperreflexia
investigations
1 CT head -first line for hydrocephalus detection -may detect cause (tumour) 2 CSF -indicate cause
when should a lumbar puncture not be used in hydrocephalus
in obstructive hydrocephalus
can cause tonsilar herniation and death
