Hydrocephalus Flashcards
What is hydrocephalus?
Excess CSF within the intracranial space & ventricular system causing dilation of the ventricles
Where is the majority of CS produced? How?
Choroid plexus
Actively via Na pump
How much CSF is produced/ day?
450-600cc
Hoe often does the CSF turnover each day?
3/4 times
Where does the CSF move after leaving the ventricular system?
Subarachnoid space
Where is CSF reabsorbed?
Arachnoid granulations
Where does CSF move from the arachnoid villi? How?
Venous sinuses
Passively
What are the 2 major types of hydrocephalus?
Communicating (CoH)
Non-communicating (NCH)
What is communicating hydrocephalus also known as?
Non-obstructive
What is non-communicating also known as?
Obstructive
In CoH, where is the problem observed?
Most commonly due to CSF resorption rather than over production of CSF
What are some of the signs & symptoms observed in CoH?
In infants - increase in head Headache Nausea & vomiting Papillodema 6th nerve palsy Focal neurological deficit
What are some of the causes of CoH?
Subarachnoid haemorrhage
Head trauma
Infective (bacterial meningitis)
When does NCH occur?
When there is any physical obstruction to normal CSF flow
What are some of the causes of NCH?
Aqueductal stenosis Tumours Cysts Infection Haemorrhage Congenital malformations
What is the earliest imaging evidence of hydrocephalus?
Dilation of the temporal horn of lateral ventricles
What is the treatment for hydrocephalus?
External Ventricular Drain (EVD) - drains the CSF from the ventricular system
What is the mainstay of treatment for CoH?
Shunt placement (Ventriculo-peritoneal shunt)
How can NCH be treated?
Removal of the obstructing lesion
Shunt placement
Thrid ventriculoectomy
What is one of the downsides of VP shunts?
They can fail, disconnection or cause infection
What is the mneumonic for the classic triad of NPH?
Wet, Wobbly & Wacky
What is one of the reversible causes of dementia?
Normal Pressure Hydrocephalus
What are the symptoms described by Wet Wobbly & Wacky in NPH?
Urinary incontinence
Gait disturbance
Dementia
What investigations would you do in CoH?
CT/MRI
LP - symptoms improve with CSF removal
What is the treatment for patients with NPH?
VP shunt placement
What are LPs used in the diagnosis of?
Meningitis SAH Malignancy Meningoencephalitis Infusion of drugs
What are some contraindications for LP?
Increased ICP
Bleeding disorder
Infection at site
What needle helps to reduce spinal shock in LP?
Atraumatic
At what level do you perform LP?
L3-4 (L4/5)
What position should the patient lie at?
Lateral Decubitus Position
Which way should the bevel face when performing LP?
Up to keep parallel with nerve/ ligament fibres
What ligament will you pierce when performing LP?
Ligamentum flavum
How can you assess opening pressure in LP?
Attach manometer
How many vials do you take when doing an LP? What are they for?
3
1: Culture & gram stain
2: Glucose & protein
3: Cell count & differential
What are some complications of LP?
Back pain Spinal headache Bleeding or fluid leak Infection Nerve trauma Brainstem herniation
What is the most common complication of LP?
Spinal headache
How can you reduce the complications including spinal headache?
Supine position
Caffeine
Hydration
In coning or tonsillar herniation, what are the presenting signs?
Altered mental status
Cranial nerve abnormalities
Cushing triad - bradycardia
How would you manage a patient who presents with coning?
Raise bed
Mannitol or 3% saline
Intubate patient
If you are sending sample for xanthochromia what are you testing for? and what should the sample be contained in?
Blood
Brown paper envelope
