Hydrocephalus

Question 1

patient presents with 3wk history of worsening headache , trouble walking and visual impairment … may be sign of?

Answer 1

Neoplastic: metastasis, meningioma, prim glial tumour
Infectious abscess
Vascular: intracerebral haemorrhage
Hydrocephalus secondary to neoplasm?

Question 2

approach for patient?

Answer 2

ABCDE

Question 3

what lab tests may you want to take

Answer 3

FBC, U+E, clotting screen

Question 4

investigations?

Answer 4

urgent CT head,

Question 5

if there is a lesion in the cerebellum, what features might you find on examination or history

Answer 5

DANISH 
Disdiadochikinesis
Ataxia
nystagmus
intentional tremor
slurred speech
Hypotonia

Question 6

if there is a lesion in the cerebellar vermis what might this show on examination

Answer 6

truncal ataxia and a broad based gait

Question 7

a cerebellar hemispheric lesion would cause what on examination

Answer 7

loss of co-ordination ipsilaterally, intentional tremor, past pointing, disdiadochokinesis and nystagmus.

Question 8

What is CSF

Answer 8

clear, proteinaceous fluid that bathes the CNS.

Question 9

functions of CSF (3)

Answer 9

protects brain from BD by buffering the brain,

excretes waste products( harmful drugs or metabolites and transports hormones

Question 10

How much CSF is circulating at any given moment

Answer 10

150ml - 17% is in the ventricles

remaining is in cisterns and subarachnoid space

Question 11

where is CSF formed

Answer 11

choroid plexuses (specialised vascular tissue)

Question 12

where are the choroid plexuses located

Answer 12

lateral ventricles, 3rd and 4th

Question 13

where does CSF flow from the lateral ventricles

Answer 13

through the right and left foramen of Munro (interventricular foramen) into the third ventricle.
Next, it flows through the aqueduct of Sylvius into the fourth ventricle.

Question 14

the 4th ventricle is anterior to what

Answer 14

cerebellum

Question 15

from the 4th ventricle, where does CSF exit?

Answer 15

may exit the foramen of Luschka laterally or the foramen of Magendie medially into the subarachnoid space..

Question 16

What happens when CSF passes the foramen of Magendie ?

Answer 16

filling of subarachnoid space

Question 17

what is the cerebellomedullary cistern

Answer 17

the level at which CSF enters the subarachnoid space

Question 18

What is CSF flow largely dependent on?

Answer 18

the cardiac cycle

Question 19

During systole, what happens to the brain vasaculture

Answer 19

expands and compresses the lateral the 3rd ventricle, forcing CSF down the cerebral aqueduct

Question 20

What happens to CSF flow in diastole

Answer 20

CSF flows down the cerebral aqueduct

Question 21

How is CSF reabsorbed into the bloodstream?

Answer 21

outpouchings into the superior sagittal sinus = arachnoid granulations

Question 22

what is the pressure dependent gradient for CSF

Answer 22

when the CSF pressure is greater than the venous pressure, CSF will flow into the superior sagittal sinus

Question 23

even if CSF is lower than the venous pressure, the arachnoid villi will not ..?

Answer 23

let blood pass into the venous system

Question 24

where does CSF flow after the superior sagittal sinus?

Answer 24

transverse sinus via the confluence of the sinus’s

Question 25

From the confluence of sinus’s where does CSF enter?

Answer 25

sigmoid sinus followed by the internal jugular vein

Question 26

what are the 2 main types of hydrocephalus ?

Answer 26

Communicating (non-obstructive) vs non-communicating (obstructive).

Question 27

what is the difference between the 2 types of hydrocephalus ?

Answer 27

non -com = structural blockage within the ventricular system

com = impaired CSF absorption

Question 28

causes of non-communicating

Answer 28

congenital, obstructing lesion

Question 29

causes of communicating

Answer 29

SUB arc H, infective meningitis, normal pressure hydrocephalus, congenital

Question 30

NPH hydrocephalus - triad?

Answer 30

Hakim’s/Adam’s triad

Question 31

what does Hakim’s triad consist of?

Answer 31

dementia, gait disturbances and urinary incontinence

Question 32

lesions in the cerebellum if large enough can compress?

Answer 32

the 4th ventricle and effect the CSF flow

Question 33

how can you treat hydrocephalus surgically?

Answer 33

external ventricular drain (VED)

Question 34

What is an EVD

Answer 34

thin drainage tube that sits outside the patients head with its tip in the ventricular system - end is connected to measurement an can be used to monitor ICP

Question 35

in an EVD, how can the amount of CSF drainage be controlled ?

Answer 35

raising or lowering the external drainage system to different pressures on the pressure scale

Question 36

how can long term persisting communicating hydrocephalus be treated

Answer 36

CSF diversion procedure

ventriculo-peritoneal (VP) shunt

Question 37

different shunts that can be used?

Answer 37

lumbo-peritoneal - LPS
ventriculo-pleural - VPS
ventriculo-atrial - VAS

Question 38

What is a shunt

Answer 38

allows excess CSF to drain to other parts of the body

Question 39

what are the 3 main parts of a shunt

Answer 39

an inflow catheter - drains CSF from vesicles
a valve mechanism - regulates pressure
an outlfow catheter - csf from valve

Question 40

name some complications of shunting

Answer 40

over-drainage, (ow pressure headaches, subdural haematoma)
under-drainage… blockage… infection… disconnection… seizures… distal end problems (abdominal hernias (VPS)… cardiac arrhythmias (VAS).

Question 41

in babies hydrocephalus may show with

Answer 41

rapid head growth, vomiting