Aria Fallah, MD, MSc, FRCSC FAANS, FAAP
Assistant Professor
Department of Neurosurgery
Hydrocephalus after hemispherectomies and other
resective surgeries
Pediatric Epilepsy Surgery Conference and Family Reunion
No conflicts of interest
2
Objectives
• Overview of the brain's ventricular system and CSF
physiology
• Explain the Monroe Kellie hypothesis in the context of
hydrocephalus
• Diagnosis of hydrocephalus
• Discuss management options for hydrocephalus
3
4
Anatomy of the ventricular system
CSF production
• For each drop of CSF produced , the same amount
should be absorbed
• Infants and children produce
0.33 ml/kg/hr
• Adult = 125mL ; 20 mL in the ventricle
• In General 15-20mL CSF is made hourly
5
Where is CSF produced?
• Choroid Plexus – 50-85%
Extrachoroidal sources – up to 30%
• Ependymal layer
• Brain parenchyma
• Spinal subarachnoid spaces
6
Where is CSF absorbed?
• Arachnoid villi – primary site
Other sites
• Lymphatic drainage
• Brain capillaries
• Choroid Plexus
7
Physiology
8
Skull is a closed box, “mostly inelastic”
Monroe-Kellie doctrine:
•Sum of volumes of brain, CSF and intracranial blood
is constant and incompressible
•Increase in volume can lead to significant raise in ICP
•Brain has limited compliance
Alexander Monroe
(physicist)
9
What is Hydrocephalus?
•An imbalance between the production and absorption of
cerebral spinal fluid (CSF)
•This results in an increased volume and an increase in
intracranial pressure
•*May or may not be associated with a change in the
ventricular size
10
FACTS
• Hydrocephalus is Common
• Affects 1 or 2 of every 1000 babies born
• Most common reason for neurosurgery in children
• There is No Cure
• No effective medical therapy
• The only effective treatments are surgical
• It is often a life-long condition
• Children with hydrocephalus require long-term follow-up
11
Hydrocephalus
• Due to increased production of CSF
• Due to obstruction in fluid pathways
• Due to impaired absorption
12
Anatomic hemispherectomy
13
• Highest chance for blood loss
• Highest risk of hydrocephalus
• Most certain procedure to ensure
disconnection
• Indicated for persistent seizures after
functional hemispherectomy
Hydrocephalus following an anatomic
hemispherectomy
14
In up to a third of patients
Hydrocephalus
• Due to increased production of CSF
• Due to obstruction in fluid pathways
• Due to impaired absorption
15
Evolution of hemispherectomy techniques
16
• Smaller craniotomy
• Reduced operative time
• Reduced blood loss
• Decreased risk of
infection
• Decreased risk of
developing
hydrocephalus
Decreasing the risk of hydrocephalus following
hemispherectomy
• Disconnective hemispherectomy as opposed to
resective hemispherectomy
• Decreasing blood loss at the time of surgery
• Decreasing the amount of blood inside the ventricular
system
• Aggressive drainage of CSF following hemispherectomy
17
“Baby’s Soft spot”
18
Head circumference chart
Detecting hydrocephalus
Symptoms and Signs in Infants
• Abnormally increase in head size
• Drowsiness
• Irritability
• Poor feeding / Vomiting
• Breath-holding Spells, Slow heart rate, Bulging
and Tense Fontanel
• Head circumference growing faster than
expected
19
Symptoms and Signs in Older Children
20
• Headaches
• Learning problems
• Nausea and Vomiting
• Drowsiness
• Loss of coordination and difficulty walking
• Swelling of the optic nerve
• Inability to look up
Diagnosing hydrocephalus
21
CT
Ventricular shunt Cavity shunt
Natural history of untreated hydrocephalus
• ½ untreated patients die
• ½ survive with “arrested hydrocephalus”
• Of these, 15% have normal cognitive and neurologic findings
22
Shunt components
23
Ventricular catheter
Valve
Distal Catheter
Ventriculoperitoneal shunt
24
Journal of Neurosurgery: Pediatrics
Alternative sites
•Pleural cavity
•Atrium
Types of valves
25
Types of valves
1. Differential Pressure Valves
• Constant Differential Pressure
regardless of flow
1. Flow-regulated Valves – constant
flow
• Constant flow regardless of differential
pressure
1. Anti-siphon devices
2. Programmable valves
26
Source: Drake et al. 1998
Shunt complications
• 3 types:
• Mechanical failure – improper placement, migration, obstruction,
fracture, disconnection
• Infection/skin problems
• Functional failure (inadequate flow rate of a functioning shunt)
• 3 origins:
• Shunt
• Patient
• Surgeon
27
Complications
• Early complications: hematoma, bowel injury
• Infection: most commonly in first 3 months, 90% of
shunt infections within 6 months
• Most common: Proximal shunt obstruction
28
Management of shunt malfunction
• Confirmation of diagnosis
• CT scan/FAST MRI, shunt series
• Shunt tap
• Site of malfunction
• Rule out infection – fever, abdominal pain, CRP, ESR
29
Three types of shunt patients
30
31
Endoscopic Treatment
32
Is one better than the other?
33
Kestle et al. Childs Nerv Syst (2009)
Addition of Choroid Plexus Cauterization
34
Are we able to predict success?
35
with choroid plexus
cauterization
ETV Success Score
Warf BC, et al. J Neurosurg Pediatr 5:143-148, 2010Kulkarni AV, et al.. J Pediatr 155:254-259.e251, 2009
36
Results of ETV and CPC
Weil, A.G., Westwick, H., Wang, S. et al. Childs Nerv Syst (2016)
Prognosis in hydrocephalus
• Neurologic and intellectual disabilities depend on:
• Cause of hydrocephalus
• Thickness of the brain and corpus callosum
• Requirement for a shunt
• Presence of other brain anomalies
• Associated conditions: IVH, infection, etc. may play a larger role
than the hydrocephalus alone.
37
How should we measure success?
• Number of operations?
• Quality of life
• Neuropsychological
• Education/Job
• Social interactions
38
Conclusion
• Hydrocephalus is a deceptively complex disorder
• Careful consideration of the cause of hydrocephalus is
required in all cases
• This may affect decision making, family counseling,
prognosis and outcome
39
40
Resources
http://www.hydroassoc.org/
https://medlineplus.gov/hydrocephalus.html
Hydrocephalus After Hemispherectomy And Other Resective Procedures

Hydrocephalus After Hemispherectomy And Other Resective Procedures

  • 1.
    Aria Fallah, MD,MSc, FRCSC FAANS, FAAP Assistant Professor Department of Neurosurgery Hydrocephalus after hemispherectomies and other resective surgeries Pediatric Epilepsy Surgery Conference and Family Reunion
  • 2.
    No conflicts ofinterest 2
  • 3.
    Objectives • Overview ofthe brain's ventricular system and CSF physiology • Explain the Monroe Kellie hypothesis in the context of hydrocephalus • Diagnosis of hydrocephalus • Discuss management options for hydrocephalus 3
  • 4.
    4 Anatomy of theventricular system
  • 5.
    CSF production • Foreach drop of CSF produced , the same amount should be absorbed • Infants and children produce 0.33 ml/kg/hr • Adult = 125mL ; 20 mL in the ventricle • In General 15-20mL CSF is made hourly 5
  • 6.
    Where is CSFproduced? • Choroid Plexus – 50-85% Extrachoroidal sources – up to 30% • Ependymal layer • Brain parenchyma • Spinal subarachnoid spaces 6
  • 7.
    Where is CSFabsorbed? • Arachnoid villi – primary site Other sites • Lymphatic drainage • Brain capillaries • Choroid Plexus 7
  • 8.
    Physiology 8 Skull is aclosed box, “mostly inelastic” Monroe-Kellie doctrine: •Sum of volumes of brain, CSF and intracranial blood is constant and incompressible •Increase in volume can lead to significant raise in ICP •Brain has limited compliance Alexander Monroe (physicist)
  • 9.
  • 10.
    What is Hydrocephalus? •Animbalance between the production and absorption of cerebral spinal fluid (CSF) •This results in an increased volume and an increase in intracranial pressure •*May or may not be associated with a change in the ventricular size 10
  • 11.
    FACTS • Hydrocephalus isCommon • Affects 1 or 2 of every 1000 babies born • Most common reason for neurosurgery in children • There is No Cure • No effective medical therapy • The only effective treatments are surgical • It is often a life-long condition • Children with hydrocephalus require long-term follow-up 11
  • 12.
    Hydrocephalus • Due toincreased production of CSF • Due to obstruction in fluid pathways • Due to impaired absorption 12
  • 13.
    Anatomic hemispherectomy 13 • Highestchance for blood loss • Highest risk of hydrocephalus • Most certain procedure to ensure disconnection • Indicated for persistent seizures after functional hemispherectomy
  • 14.
    Hydrocephalus following ananatomic hemispherectomy 14 In up to a third of patients
  • 15.
    Hydrocephalus • Due toincreased production of CSF • Due to obstruction in fluid pathways • Due to impaired absorption 15
  • 16.
    Evolution of hemispherectomytechniques 16 • Smaller craniotomy • Reduced operative time • Reduced blood loss • Decreased risk of infection • Decreased risk of developing hydrocephalus
  • 17.
    Decreasing the riskof hydrocephalus following hemispherectomy • Disconnective hemispherectomy as opposed to resective hemispherectomy • Decreasing blood loss at the time of surgery • Decreasing the amount of blood inside the ventricular system • Aggressive drainage of CSF following hemispherectomy 17
  • 18.
    “Baby’s Soft spot” 18 Headcircumference chart Detecting hydrocephalus
  • 19.
    Symptoms and Signsin Infants • Abnormally increase in head size • Drowsiness • Irritability • Poor feeding / Vomiting • Breath-holding Spells, Slow heart rate, Bulging and Tense Fontanel • Head circumference growing faster than expected 19
  • 20.
    Symptoms and Signsin Older Children 20 • Headaches • Learning problems • Nausea and Vomiting • Drowsiness • Loss of coordination and difficulty walking • Swelling of the optic nerve • Inability to look up
  • 21.
  • 22.
    Natural history ofuntreated hydrocephalus • ½ untreated patients die • ½ survive with “arrested hydrocephalus” • Of these, 15% have normal cognitive and neurologic findings 22
  • 23.
  • 24.
    Ventriculoperitoneal shunt 24 Journal ofNeurosurgery: Pediatrics Alternative sites •Pleural cavity •Atrium
  • 25.
  • 26.
    Types of valves 1.Differential Pressure Valves • Constant Differential Pressure regardless of flow 1. Flow-regulated Valves – constant flow • Constant flow regardless of differential pressure 1. Anti-siphon devices 2. Programmable valves 26 Source: Drake et al. 1998
  • 27.
    Shunt complications • 3types: • Mechanical failure – improper placement, migration, obstruction, fracture, disconnection • Infection/skin problems • Functional failure (inadequate flow rate of a functioning shunt) • 3 origins: • Shunt • Patient • Surgeon 27
  • 28.
    Complications • Early complications:hematoma, bowel injury • Infection: most commonly in first 3 months, 90% of shunt infections within 6 months • Most common: Proximal shunt obstruction 28
  • 29.
    Management of shuntmalfunction • Confirmation of diagnosis • CT scan/FAST MRI, shunt series • Shunt tap • Site of malfunction • Rule out infection – fever, abdominal pain, CRP, ESR 29
  • 30.
    Three types ofshunt patients 30
  • 31.
  • 32.
  • 33.
    Is one betterthan the other? 33 Kestle et al. Childs Nerv Syst (2009)
  • 34.
    Addition of ChoroidPlexus Cauterization 34
  • 35.
    Are we ableto predict success? 35 with choroid plexus cauterization ETV Success Score Warf BC, et al. J Neurosurg Pediatr 5:143-148, 2010Kulkarni AV, et al.. J Pediatr 155:254-259.e251, 2009
  • 36.
    36 Results of ETVand CPC Weil, A.G., Westwick, H., Wang, S. et al. Childs Nerv Syst (2016)
  • 37.
    Prognosis in hydrocephalus •Neurologic and intellectual disabilities depend on: • Cause of hydrocephalus • Thickness of the brain and corpus callosum • Requirement for a shunt • Presence of other brain anomalies • Associated conditions: IVH, infection, etc. may play a larger role than the hydrocephalus alone. 37
  • 38.
    How should wemeasure success? • Number of operations? • Quality of life • Neuropsychological • Education/Job • Social interactions 38
  • 39.
    Conclusion • Hydrocephalus isa deceptively complex disorder • Careful consideration of the cause of hydrocephalus is required in all cases • This may affect decision making, family counseling, prognosis and outcome 39
  • 40.

Editor's Notes

  • #11 Most common disorder treated by pediatric neurosurgeons Over 30,000 shunts are placed annually in the united states. CSF constantly produced and absorbed.
  • #27 Siphon resisting valves prevent against siphoning. (Delta and other types of valves)