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  • Raised/increased intracranial pressure

  • 331.4 Hydrocephalus

  • G91.9 Hydroycephalus (acquired) (external) (internal) (malignant) (recurrent)


  • Increased intracranial pressure (ICP) beyond what cranium and vertebral column can accommodate
  • Reduced cerebrospinal fluid (CSF) production, decreased cerebral blood volume

Essentials of Diagnosis

  • Change in ICP for a given change in intracranial volume is called intracranial compliance
  • Normal compliance curve begins steep rise at approximately 25 mmHg
  • If brain, blood, CSF volumes continue to increase, accommodative mechanisms fail and ICP rises exponentially
  • Diagnosis made via monitoring intracranial pressure
    • Above 25 mmHg considered hydrocephalus

General Considerations

  • Numerical difference between ICP and mean blood pressure in cerebral vessels is the cerebral perfusion pressure
    • A widespread reduction in cerebral perfusion occurs as ICP approaches the mean systemic blood pressure, resulting in ischemia and brain death
    • Reduced cerebral perfusion pressure can result in cerebral infarction
  • Normal ICP range between 2 to 5mmHg


  • Hydrocephalus can occur in any age group

Signs and Symptoms

  • Headache
  • Neck pain
  • Nausea
  • Vomiting
  • Drowsiness
  • Ocular palsy
  • Papilledema
  • Confusion
  • Gait disturbance
  • Positive Babinski
  • Increased tone in limbs

Functional Implications

  • Decreased cognitive or physical interaction with environment
  • Poor safety with gait and balance activities
  • Decline in judgment or problem solving
  • Decline or loss of independence with ADLs
  • Inability to participate school, work, recreational activities

Possible Contributing Causes

  • Cerebral or extracerebral mass (tumor, edema, abscess)
  • Generalized brain swelling
  • Increased venous pressure (venous sinus thrombosis, heart failure)
  • Choroid plexus tumor
  • Meningitis
  • Ventricle obstruction
  • Chiari malformation
  • Arteriovenous malformation
  • Myelomeningocele

Differential Diagnosis


  • CT for detailed imaging of brain

Diagnostic Procedures

  • ICP monitoring
  • Lumbar puncture with progressive fluid reduction

  • To ER physician if acute onset
  • To neurologist for monitoring
  • To neurosurgeon for shunt placement if patient is a candidate
  • Other services as needed based on impairments (occupational therapy, speech therapy, neuropsychologist)

  • Attention
  • Cognition
  • Motor planning
  • Cranial nerve integrity
  • Gait
  • Sitting and standing balance (static and dynamic)
  • Muscle strength, coordination
  • Postural control
  • Muscle tone
  • Sensation
  • Bed mobility
  • Transfers
  • Endurance
  • Self-care
  • Home management
  • Fine-motor control

  • Glasgow Coma Scale
  • ...

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