2. Definition: Abnormal collection of cerebrospinal fluid
(CSF) resulting in abnormal widening of spaces in the
brain
Greek word: Hydro - Cephalus
3. Physiology and circulation of CSF
- Normal volume of circulating CSF is around 150ml
- Daily production is about 500ml/day, 20ml/hr
Function:
- Protects and support the brain and spinal cord.
-Transport medium for transmitters and as a method of
removing the end-products of metabolism.
9. Types of hydrocephalus
1. Communicating and Non-communicating
2. Acute and chronic
3. Congenital and acquired
Hydrocephalus Ex Vacuo
Arrested hydrocephalus
10. Non-communicating (obstructive): CSF circulation is
blocked at or proximal to fourth ventricular outlet
foramina.(enlargement of ventricles proximal to the
block) – Aqueduct stenosis, tumors
Communicating (non-obstructive): At the level of the
cisterns, the subarachnoid space or the level of the
arachnoid granulation
- Post meningitis, post hemorrhagic
11. 1. Congenital : Present at birth or few
weeks/months after birth (1-2/1000 live births)
Aqueduct stenosis
Chiari malformations
Dandy-Walker malformation
2. Acquired
Infection (post-meningitis)
Post – hemorrhagic (SAH,IVH)
Tumors
12. 1. Acute : Develops within days or few weeks
- Manifests with rapid progression of symptoms -
Requires early attention and treatment
hydrocephalus caused by tumor
2. Chronic : Over months (or even years)
- Subtle signs of memory impairment, walking
difficulty, urinary incontinence
- A classic example is NPH
Chronic hydrocephalus can present acutely
because of changes in the pathophysiology of the
CSF absorption or flow.
13. Structural characteristics
- Dilatation of temporal and frontal horns of the
lateral ventricles
- Enlargement of ant. or post recesses of 3rd
ventricle
- Narrowing of ventricular angle
- Effacement of cortical sulci
14. Clinical Features
Due to increased ICP and dilation of ventricles,
causing compression of the adjacent brain
In neonatal period
Skull - thin and relatively non rigid allows for an
overall cranial expansion
Craniofacial disproportion
Irritable Fussy
May not accept feeds Vomiting
Poor head control Lethargy
Drowsiness
In extreme cases, lapse into a comatose state
15. Cont….
- Fontanel full , bulging and wide
- Thin and glistening scalp with enlargement and
engorgement of scalp veins
- Macewen's sign ( cracked pot sound on head
percussion)
- Sixth nerve (abducens) palsy
- Setting sun sign - upward gaze palsy
- Hyperactive reflexes.
- Irregular respiration with apneic spells.
- Separation of cranial sutures (sutures diastasis)
16.
17.
18. In older children and adults
The enlarging ventricles result in raised ICP and
compression of the adjacent brain
2 common modes of presentation
a) rapidly progressive hydrocephalus
b) chronic hydrocephalus.
19. Rapidly progressive hydrocephalus
Increased ICP - new-onset headache and vomiting
If untreated, these symptoms worsen and blurring of vision
often occurs.
In patients with long-standing raised pressure, papilledema
can result
If still untreated, drowsiness and progression to coma
follow.
20. Chronic hydrocephalus
- CSF accumulates more slowly - gradually
compressing the brain
- Predominantly seen in older adults
- The patient becomes progressively dull,
apathetic, and uninvolved with the surroundings.
- Memory impairment for recent events is commonly
seen, but usually the remote memory is well
preserved.
21. - Short stepped gait with a wide stance and unsteadiness
- Urinary incontinence
- No significant headache
Cerebellar fits or hydrocephalic attacks:
(severe headache, patient lapses into sudden
unconsciousness associated with a decerebrate or
decorticate response, downward deviation of the
eyeballs, and respiratory distress)
Medical emergency
22. Investigation
Ultrasonography to visualize the ventricular
system(when the anterior fontanelle is patent)
CT /MRI of the head
LP in cases of communicating hydrocephalus for both
diagnostic and therapeutic
23. Management
The ultimate goal is to reverse the neurologic
damage caused by the raised ICP
Medical treatment - not proved to be useful
Used as a temporary measure and in
conjunction with surgical management.
Acetazolamide - Commonly used - reduce CSF
production.
However, benefits are minimal and high doses of
the drug, which cause metabolic acidosis, are
required to achieve the effect.
24. Surgical
Involves diversion of the accumulated CSF
(1) by reopening the obstruction to allow the CSF
to flow into its natural pathway
(2) by creating a diversion before the obstruction
to allow the CSF to drain into the intracranial
pathways distal to the block
(3) by diversion of the CSF into another cavity so
it becomes absorbed into the bloodstream.
Removal of obstruction like posterior fossa tumor
25. Although shunts have been the mainstay of
treatment for several decades, endoscopic
procedures have now become more popular.
These include:
i) Endoscopic third ventriculostomy- into the
basal cisterns
ii) Endoscopic aqueductoplasty – 3 fr forgarty
catheter
iii) Endoscopic aqueductal stenting.
26. CSF diversion procedure :
- Children <5 years : difficult to assess intellectual
development
- Protects against the effects of persistent ventriculomegaly
and ensures an optimal environment for future intellectual
development
- >5 years and adults with asymptomatic ventriculomegaly
often are closely watched, with frequent assessment
of intellectual development, before considering a shunt
insertion.
27. Cerebrospinal Fluid Shunts
-Ventriculo-peritoneal(VP) - most common
-Ventriculo-atrial(VA)
-Torkildsen shunt (in aqueduct stenosis by passing a
catheter from the lateral ventricles into the cisternal
space)
-Lumbo-peritonial shunt.
-External drainage – temporary
28.
29. Complications of shunts
Shunt malfunction Infection
Obstruction. Acute hemorrhages
Over drainage Hematoma
Disconnections Seizure
Distal Complication
Ascitis
Pseudoperitoneal cyst
30. Normal-Pressure Hydrocephalus
- Older patients with excessive accumulation of the
CSF in the intracranial compartment leading to
dilation of the ventricles and subarachnoid spaces
- The clinical picture is typically of an older patient
who presents with the triad of
gait ataxia, dementia, and urinary incontinence
31. Exact cause unknown - reduced absorption
-ICP not usually raised - brain parenchyma is less stiff
to allow it to be compressed by the developing
ventriculomegaly
-Diagnosis: combination of clinical features with
prominent ventricles seen by CT /MRI, with no other
abnormalities.
- A therapeutic trial of CSF drainage has been used
for patients suspected of having NPH to predict
response to treatment.