Hydrocephalus Flashcards
What is hydrocephalus
Excess cerebro-spinal fluid within the intracranial space leading to dilation and ventricles and increased intracranial pressure
What is the tow distinctions of hydrocephalus
Communicating hydrocephalus
Non Communicating hydrocephalus
What is the pathology of communicating hydrocephalus
Problem with CSF re-absorbtion
(production> reabsorption)
Overproduction of CSF
What is the main pathology of communicating hydrocephalus
Problem with CSF reabsorption - as cannot keep the pace of CSF production
What is cause of overproduction go CSF leading to communicating hydrocephalus
Choroid plexus papillomas
What is the signs and symptoms of communicating hydrocephalus in a child whose sutures have not yet fused
there is disproportional increase in head circumference compared to the rest of the face/body
Failure to thrive
What causes the sighs and symptoms of hydrocephalus in children with fused sutures and adults
The increased intracranial pressure
What is the signs and symptoms of adults with communicating hydrocephalus
Papilledema
Headache
Nausea/vomiting
Up gaze difficulty
gait disturbance
What is the aetiology of communicating hydrocephalus
Infection
Subarachnoid haemorrhage
Post-operative
Head trauma
What infection has a high incidence of hydrocephalus
Meningitis
How does subarachnoid haemorrhage lead to acute communicating hydrocephalus
Blood and blood breakdown products cause scarring of arachnoid granulation
Why would acute communicating hydrocephalus where is CSF reabsorption is significantly and suddenly reduced present as an emergency
The neurological decline is rapid
What can be seen in emergency communicating hydrocephalus
patients presents as sleep then obtunded then requiring intubation
What occurs in non communicating hydrocephalus
Occurs whenever there is any physical obstruction to normal flow of CSF before it leaves the ventricles
What is the pathology of non communicating hydrocephalus
Obstruction likely to come acutely as results from CSF follow obstruction at any point along the intra-ventricular pathway
What is the causes of non communicating hydrocephalus
Aqueductal stenosis
Tumours/cancers/masses
Cysts
Infection
Haemorrhage
hematoma
Congenital malformation
How is hydrocephalus investigated
Radiography
CT/MRI
What are the early signs seen in radiography of hydrocephalus
dilation of temporal horns of the lateral ventricles
What can be seen in radiography of hydrocephalus
Third ventricle becomes ballooned
Lateral ventricle size increases
Peripheral sulci erased
What diagnostic techniques shows ventriculmomegaly has occurred in a radiography of hydrocephalus
Evans ratio - the ratio of the maximum width of the anterior horns of the lateral ventricles to the maximum width of the calvarium at the same level of the foramen mono
if greater than 0.3 `(30%) = venticulomegaly
What is the surgical treatment for emergency acute hydrocephalus
External ventricular drain
What is the problems with external ventricular drain
Cannot be maintained indefinitely
Some patients unable to tolerate weaning/clamping of EVD prior to removal
Infection risk is high
What is the treatment of communicating hydrocephalus
Shunt placement
- ventriculoperitoneal
- lumbar peritoneal
- ventriculoatrial (if peritoneal failure)
When would patients be given a permanent shunt placement
If patient cannot tolerate EVD
Weeks or months after EVD
What is the most frequent shunt
Ventroperitoneal
What is the problem with lumbar peritoneal
Overdrainage
The indecent of shunt failure is high, what is the common causes
Mechanical failure from occlusion
disconnection migration
Overdrainage/underdrainage
Infection
skin erosion
What is a sign of shunt failure
Headache (always investigate)
What is the three treatment options for non communicating hydrocephalus
Removal of obstructive lesson
Shunt placement
Third ventriculostomy
What is often performed in junction with third ventriculostomy
Ventriculoperitoneal shunt
What occurs in third ventriculostomy
Hole is opened in floor of third ventricle so CSF flows out into the interperduncular cistern and pre-pontine space by passing cerebral aqueduct
What is a rare preventable and/or reversible cause of dementia
Non pressure hydrocephalus
What is the classic triad of non pressure hydrocephalus
WET- Urinary incontinence
WOBBY - Gait disturbance (wide stance, short and shuffle steps)
WACKY - rather quickly progressive dementia
What are the investigation of non pressure hydrocephalus
CT/MRI
Gait assessment
Mini-mental state examination
Lumpar puncture
What occurs with lumbar puncture and normal pressure hydrocephalus
Symptoms improve with CSF removal
What is the common treatment for non pressure hydrocephalus
Ventricoperitoneal shunt
what is the order of improvement in symptoms in the treatment of non pressure hydrocephalus
Most likely symptoms to improve Gait > incontinence> memory
Why is it important to have an early diagnosis of non pressure hydrocephalus
Chance of outcome is improved if symptoms have been present for shorter periods of time so failure to recognise delays treatment and lessens their chances
What is non pressure hydrocephalus usually diagnosed as and how is this a problem
Many patients with NPH to be diagnosed with alzheimers or age related dementia. therefore never seek treatment
