Dr. Pedro Roldán Ramos
Neurosurgeon · Spine, functional and brain
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Neurovascular
Cerebrovascular surgery: aneurysms and malformations
Surgical treatment of intracranial aneurysms and arteriovenous malformations (AVMs). Microsurgical clipping or coordination with the endovascular team according to the morphology and location of the lesion.
What is it?
Cerebrovascular surgery: aneurysms and malformations
Cerebrovascular surgery treats lesions in the blood vessels of the brain that can cause life-threatening haemorrhage. Intracranial aneurysms have a prevalence of 2-3% in the general population; their rupture causes subarachnoid haemorrhage with 40-50% mortality. Arteriovenous malformations (AVMs) are less common but may present with haemorrhage, seizures or headaches. The decision between open surgery and endovascular treatment is made by a multidisciplinary board.
2-3%
prevalence of aneurysms in the general population
40-50%
mortality from subarachnoid haemorrhage due to rupture
<2%
surgical risk for unruptured aneurysms in specialist centres
Symptoms
When to consult a neurosurgeon?
Unruptured aneurysms are usually asymptomatic. Symptoms of rupture or vascular injury include:
- Sudden, severe headache "the worst of my life" (classic sign of subarachnoid haemorrhage)
- Transient or prolonged loss of consciousness
- Neck stiffness, nausea and vomiting
- Double vision, eyelid drooping (third cranial nerve compression)
- Acute-onset focal neurological deficit
- Seizures (particularly in AVMs)
- Chronic pulsatile headache with intracranial bruit in AVMs
Urgent attention: A sudden "thunderclap" headache is a medical emergency · go to the emergency department immediately. The time from symptom onset to treatment is critical for prognosis.
Treatments
Which techniques do we use?
Microsurgical aneurysm clipping
Placement of a metal clip at the aneurysm neck under the microscope. Preferable for wide-neck, complex aneurysms or those at the middle cerebral artery bifurcation.
Endovascular coiling (coordinated)
Embolisation with platinum coils via a femoral catheter. Less invasive, preferred in older patients or aneurysms in difficult locations.
Microsurgical AVM resection
Complete excision of the malformation with preservation of healthy parenchyma. Requires meticulous planning with multimodal angiography.
AVM embolisation
Partial or preoperative occlusion of the malformative nidus. Reduces intraoperative bleeding and sometimes allows safer subsequent resection.
Stereotactic radiosurgery
Gamma Knife for small AVMs (<3 cm) in non-surgical locations. Occlusion in 2-3 years in 70-80% of cases.
Cerebral bypass
Surgical revascularisation in complex giant aneurysms or selected occlusive disease (Moyamoya).
Our protocol
How we approach each case
Each vascular lesion is studied with multidetector CT angiography, MR angiography and, in complex cases, digital subtraction angiography (gold standard). The decision between surgical and endovascular treatment is made at a weekly neurovascular board. In ruptured aneurysms with subarachnoid haemorrhage, surgery is performed within the first 24-72 hours to prevent rebleeding. Patients remain in a neurology ICU for 10-14 days to manage vasospasm (a frequent complication between days 3 and 14). Follow-up includes MR or CT angiography at 6 months, 1 year and then periodically.
Perioperative protocol
How we organise each case
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1 · Preoperative workup
CT angiography and digital cerebral angiography (gold standard). Joint assessment with interventional neuroradiology and vascular neurology. Spetzler-Martin classification for AVMs and PHASES score for unruptured aneurysms.
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2 · Surgery
Choice of open technique (clipping) or endovascular approach according to the lesion. Neurophysiological monitoring, intraoperative angiography or microvascular Doppler to verify complete occlusion.
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3 · Immediate postoperative period
Neurocritical ICU. Vasospasm surveillance in ruptured aneurysms (days 4-14). Strict blood pressure control.
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4 · Discharge and follow-up
Variable (2 days for endovascular unruptured aneurysms to 14-21 days in SAH). Follow-up with MR/CT angiography at 3, 6 and 12 months.
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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Outcomes
Prognosis and recovery
In unruptured aneurysms treated at specialist centres, combined morbidity-mortality is below 5%. In ruptured aneurysms with a good clinical grade (WFNS I-II), 60-70% recover functional independence. Complete obliteration after clipping is 95%, higher than the 85% achieved with coiling. In AVMs treated surgically, the complete obliteration rate exceeds 90% for Spetzler-Martin grades I-III. Long-term follow-up is essential because new aneurysms may form (5% at 10 years).
Frequently asked questions
Answers to your questions
What is a cerebral aneurysm and when should it be treated?
It is an abnormal dilation of a cerebral artery that can rupture and cause subarachnoid haemorrhage (overall mortality of 40-50% if it ruptures). Ruptured aneurysms require urgent treatment; unruptured aneurysms are treated when they are >5-7 mm, have irregular morphology or there is a family history.
Which is better: surgical clipping or endovascular coiling?
Both techniques have their indications. Microsurgical clipping allows definitive occlusion and is preferable for wide-neck, complex aneurysms or those at the middle cerebral artery bifurcation. Endovascular coiling is less invasive and preferred in older patients or aneurysms in difficult locations. The decision is made by the board.
What is an arteriovenous malformation (AVM)?
It is an abnormal connection between cerebral arteries and veins without intermediate capillaries, creating a high-flow shunt. It may present with haemorrhage, seizures or headaches. Treatment depends on the Spetzler-Martin scale (grades I-V) and includes surgery, embolisation, radiosurgery or combinations.
How long does recovery take after cerebrovascular surgery?
After clipping of an unruptured aneurysm: 5-7 days in hospital, progressive return to activity over 6-8 weeks. After aneurysmal rupture: depends on the clinical grade (WFNS scale); in grades I-II recovery may be complete, whereas in grades IV-V there may be permanent neurological deficits.
Can aneurysm rupture be prevented?
Low-risk aneurysms are followed with annual MR angiography. Modifiable risk factors include smoking, poorly controlled hypertension and excessive alcohol consumption. There is no evidence that controlled Valsalva manoeuvres increase the risk of rupture in unruptured aneurysms.
References
What the clinical guidelines say
"The therapeutic decision for intracranial aneurysms must be individualised by a multidisciplinary board taking into account morphology, location, age, comorbidities and patient preferences."
"Treatment of aneurysmal subarachnoid haemorrhage should be carried out within the first 24-72 hours at highly specialised neurovascular centres to minimise the risk of rebleeding."
Bibliography
Scientific references consulted
Studies and clinical guidelines on which we base our approach to this condition.
- Connolly ES. et al. Guidelines for the Management of Aneurysmal Subarachnoid Hemorrhage (AHA/ASA). Stroke. 2012. View publication
- Greving JP. et al. Development of the PHASES score for prediction of risk of rupture of intracranial aneurysms. Lancet Neurol. 2014. View publication
- Spetzler RF, Martin NA. A proposed grading system for arteriovenous malformations. J Neurosurg. 1986. View publication
- Mohr JP. et al. Medical management with or without interventional therapy for unruptured brain AVMs (ARUBA). Lancet. 2014. View publication
- Molyneux AJ. et al. International subarachnoid aneurysm trial (ISAT). Lancet. 2002. 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 aneurysm or AVM
If you have an unruptured aneurysm or an AVM has been detected, send us your angiography or CT angiography. We review your case at our neurovascular board within 24-48h.