Dr. Pedro Roldán Ramos
Neurosurgeon · Spine, functional, and brain surgery
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Cerebrospinal fluid
Hydrocephalus and Chiari malformation
Comprehensive treatment of cerebrospinal fluid disorders in adults and children: communicating and obstructive hydrocephalus, adult normal-pressure hydrocephalus, Chiari malformation, and arachnoid cysts.
What is it?
Hydrocephalus and Chiari malformation
Hydrocephalus is the abnormal accumulation of cerebrospinal fluid (CSF) in the cerebral ventricles, causing their dilation and raised intracranial pressure. It may be obstructive (due to a block in CSF flow) or communicating (due to impaired absorption). Chiari malformation type I (descent of the cerebellar tonsils >5 mm) can cause headaches, cerebellar symptoms, and syringomyelia. Both conditions require personalised neurosurgical assessment.
1/1000
prevalence of hydrocephalus in children
70%
ETV success rate in obstructive hydrocephalus
>80%
symptomatic improvement after surgery for symptomatic Chiari
Symptoms
When to consult a neurosurgeon?
Symptoms depend on age and cause:
- Progressive headache, typically worse in the morning, improving on standing
- Rapidly increasing head circumference in infants (cardinal sign)
- Gait disturbance and loss of balance (normal-pressure hydrocephalus)
- New-onset urinary incontinence in adults
- Progressive cognitive decline (Hakim-Adams triad)
- Occipital headache worsening with Valsalva or coughing (typical Chiari)
- Cerebellar symptoms, dysarthria, or dysphagia in Chiari
- Pain, weakness, or sensory loss due to associated syringomyelia
Urgent attention: Reduced level of consciousness, persistent vomiting, or pupil changes are emergencies requiring an urgent CT scan.
Treatments
Techniques we use
Endoscopic third ventriculostomy (ETV)
Treatment of choice for obstructive hydrocephalus. An opening is made in the floor of the third ventricle for direct drainage into the subarachnoid space. Avoids implanted hardware.
Ventriculoperitoneal shunt
Shunt system for communicating hydrocephalus or failed ETV. Programmable valves adjusted non-invasively. Long-term follow-up is required.
Ventriculoatrial shunt
Alternative when peritoneal shunting is not feasible (abdominal adhesions, ascites). Direct drainage into the right atrium.
Craniovertebral decompression
Treatment of choice for symptomatic Chiari type I. Suboccipital craniectomy plus C1 laminectomy, with or without duraplasty, to increase the space and allow free CSF flow.
Endoscopic arachnoid cyst resection
Fenestration or resection of symptomatic cysts causing neurological compression or raised intracranial pressure.
ICP monitoring
In selected cases to confirm the diagnosis of normal-pressure hydrocephalus or pseudotumour cerebri by 24-72-hour continuous recording.
Our protocol
How we approach each case
Assessment includes brain and craniovertebral MRI with CSF flow sequences (phase-contrast cine MRI) to evaluate CSF dynamics. In adult normal-pressure hydrocephalus we perform a tap test (lumbar puncture with drainage of 40-60 ml) to predict the response to shunting. ETV is considered for all obstructive hydrocephalus with favourable anatomy (aqueductal stenosis, third-ventricle tumours). Shunts use the latest-generation programmable valves allowing non-invasive adjustments. In Chiari, surgery is indicated in cases with significant symptoms, documented progression, or associated syringomyelia.
Perioperative protocol
How we organise each case
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1 · Pre-operative assessment
Brain and cervical MRI (including cine MRI to study CSF flow), lumbar infusion test or tap test for adult hydrocephalus, ophthalmological assessment if raised intracranial pressure is suspected.
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2 · Surgery
For shunts: programmable valve with anti-siphon device. For ETV: neuroendoscopy with perforation of the third ventricle floor. For Chiari: posterior fossa decompression with duraplasty when indicated.
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3 · Immediate post-operative care
CT or MRI review. Serial clinical assessment (gait, continence, headache). Valve pressure adjustment in programmable shunts.
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4 · Discharge and follow-up
Discharge after 3-5 days. Follow-up MRI at one month and at 6-12 months. Patient education on signs of shunt malfunction.
Team
Neurosurgeons who treat this condition
Dr. Jorge Torales
Neurosurgeon · Skull base and spinal endoscopy
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Dr. Abel Ferrés Pijoan
Neurosurgeon · Spine, neuro-oncology, and skull base
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Dr. Jhon A. Hoyos Castro
Neurosurgeon · Spine, peripheral nerve, and skull base
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Dra. María Elena Filadoro
Neurosurgeon · Functional, epilepsy, and spine
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Dra. M. Noelia Sosa Echeverría
Neurosurgeon · Functional and stereotaxy
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Dra. Giulia Guizzardi
Neurosurgeon · Minimally invasive and skull base
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Outcomes
Prognosis and recovery
ETV achieves a 70-80% success rate in obstructive hydrocephalus and avoids the complications associated with shunts. Modern shunts have failure rates of 10-15% in the first year (infection, malfunction). Chiari surgery in selected patients achieves symptomatic improvement in over 80% of cases and stabilises or reduces syringomyelia in the majority. Typical hospital stays are 2-4 days after ETV, 3-5 days after shunting, and 4-6 days after Chiari decompression.
Frequently asked questions
Answers to your questions
What is hydrocephalus in adults?
It is an excess of cerebrospinal fluid (CSF) within the cerebral ventricles, causing their dilation and raised pressure. In adults it causes headache, gait disturbance, urinary incontinence, and cognitive decline (the Hakim-Adams triad in normal-pressure hydrocephalus).
What is endoscopic third ventriculostomy (ETV)?
It is a minimally invasive technique that creates an opening in the floor of the third ventricle to allow CSF to drain directly into the subarachnoid space, bypassing the obstruction. It is the treatment of choice for obstructive hydrocephalus and does not require a shunt implant.
When is a shunt indicated?
A ventriculoperitoneal shunt is indicated for communicating hydrocephalus, adult normal-pressure hydrocephalus, or when ETV has failed. Modern shunts are programmable, adjusted non-invasively by radiofrequency according to the required drainage pressure.
What is Chiari malformation and how is it treated?
It is the descent of the cerebellar tonsils below the foramen magnum. Type I in adults is associated with occipital headaches, neck pain, and sometimes syringomyelia. Surgical treatment (craniovertebral decompression) is indicated when there are significant symptoms or associated syringomyelia.
How long is the hospital stay after surgery?
After ETV: 2-4 days. After shunt implantation: 3-5 days. After craniovertebral decompression for Chiari: 4-6 days. Post-operative follow-up includes a control MRI and clinical assessment at 1, 3, and 12 months.
References
What the clinical guidelines say
"Endoscopic third ventriculostomy is the first therapeutic option in selected obstructive hydrocephalus, especially in cases of aqueductal stenosis."
"The surgical indication for Chiari malformation type I should be based on the presence of clear clinical symptoms or associated syringomyelia, not solely on radiological criteria."
Bibliography
Scientific references consulted
Studies and clinical guidelines on which our approach to this condition is based.
- Kulkarni AV. et al. Outcomes of endoscopic third ventriculostomy in children. Lancet. 2017. View publication
- Relkin N. et al. Diagnosing idiopathic normal-pressure hydrocephalus. Neurosurgery. 2005. View publication
- Milhorat TH. et al. Chiari I malformation redefined: clinical and radiographic findings for 364 symptomatic patients. Neurosurgery. 1999. View publication
- Friedman DI. et al. Revised diagnostic criteria for the pseudotumor cerebri syndrome. Neurology. 2013. View publication
- Rekate HL. A consensus on the classification of hydrocephalus. Childs Nerv Syst. 2011. View publication
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Patient reviews
What our patients say
High-grade glioma
"I arrived with a glioma I had been told was inoperable. Here they reviewed it at the tumour board and offered me a plan. The surgery was a success. Four years on, I am well."
Cervical disc herniation
"For years I had a cervical disc herniation, operated on by another team with no improvement. Minimally invasive surgery gave me back my mobility and took the pain away."
International patient
"I travelled from outside Spain. The team reviewed my case before I came and gave me a clear plan. Caring people and impeccable technique."
Request information
Enquiry about hydrocephalus or Chiari malformation
Send us your MRI scan (including CSF flow sequences if available) and we will assess whether surgical treatment is indicated for your case.