SOL Flashcards
causes of raised ICP§
increased CSF SOL diffuse lesion in the brain (oedema) increased venous volume physiological
hydrocephalus
accumulation of excessive css within the ventricular system of the brain
due to - obstruction to flow of CSF, overproduction, decreased resorption
CSF
normal volume 120-250ml- turnover 3-5 times a day
where is CSF produced
choroid plexus
non communicating hydrocephalus
obstruction to flow of CSF occurs within the ventricular system
Communicating
obstruction to flow of css outside the ventricular system eg subarachnoid space
effects of increased ICP
inter cranial shifts and herniation (coning)
midline shift
distortion and pressure on CN and vital neurological centres
impaired blood flow, cerebral perfusion pressure = MAP-ICP
reduced level of conciousness
what is in csf
lymphocytes neutrophils protein glucose No RBCs
clinical signs of raised ICP
papilloedema
headache
nausea and vomitting
neck stiffness
Space occupying lesion
tumours- primary brain tumours, mets
Abscess- single/multiple
haematomas- localised brain swelling eg swelling and oedema around cerebral infarct
signs of SOL
increased ICP- headache worse on lying down, bending forward or coughing, vomitting, papilloedema, decreased GCS
seizures- seen in less than 50%
evolving focal neurology- VIth nerve palsy most common due to its long course
subtle personality change
brain tumours
primary- 3% of all cancers
20% of childhood cancers
secondary- brain mets common
commonest cancers that cause brain mets
breast, bronchus, kidney, thyroid, colon, malignant melanoma
primary brain tumours
astrocytoma, glioblastoma multiforme, oligodendroglioma, enendymoma,
also - meningioma, primary CNS meningioma and cerebellar haemangioblastoma
tests for SOL
CT +/- MRI, consider biopsy, avoid LP before imaging - risks coning
