Hydrocephalus

Disease Description (Causes and Symptoms)

• Definition and pathophysiology: A disease in which cerebrospinal fluid (CSF) accumulates excessively in the ventricles and cranial cavity, causing ventricular enlargement and increased intracranial pressure (acute hydrocephalus), or in which intracranial pressure has returned to normal but ventricular enlargement remains (such as normal pressure hydrocephalus). Causes are classified as overproduction of CSF, impaired absorption, or obstruction of the circulation pathway (obstructive hydrocephalus).
• Major causes
  • Congenital: Malformations of the CSF circulation pathways, such as aqueductal stenosis
  • Acquired: Brain tumors (internal or external compression), meningitis (viral or bacterial), intracranial hemorrhage, trauma, damage to absorption sites, increased cerebral venous sinus pressure, etc.
• Clinical symptoms (summary by age)
  • Infants (with an open anterior fontanelle): Abnormally increased head circumference, bulging anterior fontanelle, downward-deviated eyes resembling a sunset (sunset sign), feeding difficulty, lethargy (floppiness), developmental delay
  • Children and adolescents: Headache, vomiting, decreased vision, behavioral and cognitive changes, memory impairment, gait disturbance and spastic paralysis of the lower limbs
  • Adults (especially normal pressure hydrocephalus): Gait disturbance (unstable center of gravity), cognitive decline (confusion and decreased memory), urinary incontinence (the triad of symptoms)
  • At all ages: Optic nerve and neurological abnormalities, such as papilledema and ophthalmoplegia, may be observed
• Complications: Cognitive and motor impairments due to brain damage, visual impairment, infection, and surgery-related complications (overdrainage, underdrainage, surgical failure, etc.)

Treatment Methods

• Basic principles: Control intracranial pressure by bypassing or normalizing CSF flow while correcting the underlying cause (tumor removal, infection treatment, etc.)
• Surgical treatment
  • Endoscopic third ventriculostomy (ETV): A procedure that creates a bypass pathway for obstructive hydrocephalus (obstruction around the internal ventricles and third ventricle). It is not applicable to all patients (generally advantageous in obstructive hydrocephalus).
  • Ventricular shunt: The most common treatment. An implanted catheter and adjustable-valve system that drains CSF from the ventricles to the peritoneal cavity (ventriculoperitoneal) or atrium (ventriculoatrial), etc. With a variable-pressure valve, the drainage pressure can be adjusted in an outpatient setting.
  • Other: Concurrent antibiotic treatment for infectious causes, and surgery or radiation therapy for the causative lesion (such as a tumor)
• Nonsurgical treatment
  • Observation (for mild symptoms or patients unable to undergo surgery), medication (when temporary reduction of intracranial pressure is needed), and rehabilitation (to improve cognitive and motor function)
• Postoperative care and preparation for complications
  • Shunt infection, obstruction, and overdrainage (intracranial hypotension, collagenous hematoma) may occur — immediate evaluation is needed if symptoms develop
  • Adjustable valves can be reset in an outpatient setting
• Lifestyle management and precautions
  • For infants, monitor head circumference and development; seek immediate evaluation if symptoms of infection (fever, vomiting, or changes in sleep) occur
  • After surgery, emergency testing is needed if trauma or acute symptoms (vomiting, lethargy, or severe headache) occur
  • Shunt patients should check whether the valve is affected in MRI or strong magnetic-field environments (bring the valve card)

Outpatient Visit Checklist (Including Sample Questions)

• Items/materials to prepare
  • List of medications currently being taken (including dosage and administration times)
  • Previous surgical records (type of shunt and date of insertion), and copies of surgical and hospitalization records
  • CDs or reports from previous imaging tests (C/T, MRI, ventriculography/radionuclide studies)
  • Record of symptom changes: onset, frequency, aggravating factors, changes in feeding, sleep, or gait, and changes in bowel movements or urination
  • For infants, records of head circumference measurements, anterior fontanelle status, and developmental milestones
• Key items the doctor will check during the outpatient visit (prepare these yourself)
  • Whether there has recently been fever, vomiting, or a change in consciousness (suspected shunt infection or obstruction)
  • Patterns of change in postoperative symptoms (headache, gait instability, or decreased vision)
  • Records of changes in usual activity and exercise levels
• Whether testing is needed
  • Emergency CT/MRI if symptoms worsen, shunt function evaluation (checking catheter location with a plain X-ray), radionuclide leakage testing, etc.

General Sample Questions to Ask the Doctor

• "For my condition, which method is recommended, surgery (ETV or shunt), and why?"
• "What are the major complications of the surgery, and how likely are they to occur?"
• "What is the schedule for follow-up tests after surgery, and what is the lifelong management plan?"
• "Are there any interactions between the medications I am taking (or other diseases I have) and the surgery or treatment?"
• "What prognosis can be expected, including differences by age and cause?"

Examples of Condition-Specific Questions

• Sample question for parents or guardians of an infant:
  • "Can it be determined whether this child’s hydrocephalus is congenital obstruction or acquired hydrocephalus (due to infection, hemorrhage, or a tumor)? Is additional genetic testing or counseling needed?"
• Sample questions for patients who have already undergone shunt surgery or their caregivers:
  • "What symptoms appear first when a shunt is blocked or infected, and when should I go to the emergency room if these symptoms occur?"
  • "If the valve I am using is a programmable valve, what procedures are required before and after an MRI scan?"

(Note: Decisions regarding diagnosis and treatment should be made in consultation with the treating medical team based on the individual patient’s clinical condition and imaging findings.)