Cerebral Vascular Malformations

Cerebral Vascular Malformations

A cerebral vascular malformation to be treated in your case] is an arteriovenous malformation (AVM), an abnormal connection between arteries and veins in the brain that is usually formed before birth.

The origin of cerebral AVM is unknown. The condition occurs when the arteries in the brain connect directly to the nearby veins without having the normal vessels (capillaries) between them.

A rupture of an AVM occurs due to pressure and damage to the blood vessel tissue. This allows blood to escape into the brain or surrounding tissues, and reduces circulation to the brain.

AVM occurs in less than 1% of people and, although the condition could be present at birth, symptoms can occur at any age.

Haemorrhages occur more frequently in people aged 15 to 20 years, but can also occur later in life. Some patients with an AVM also have cerebral aneurysms.

When is the intervention indicated?

Surgery of AVM depends on several factors, one of the most important being the form of presentation. If an AVM breaks and produces a stroke it is more likely that it bleeds again, so in most cases the decision of surgery is taken. Other factors are the patient’s age and the malformation’s size and location, principally whether the latter is close to a very functional area of the brain or in depth.

What does the operation consist of?

The surgical intervention removes the vascular malformation through a craniotomy (a window trephined in the skull), dissecting the "ball" of vessels from the normal brain till its complete extirpation. The operation must be performed without injuring any neighbouring functional areas of the brain directly or indirectly.

What are the risks, complications and possible sequelae?

This intervention is extremely complex and delicate. Anaesthesia and care at the ICU will also be very complex. There may be postoperative complications related to the surgery (haemorrhage, infection, leakage of fluid covering the brain through the wound (cerebrospinal fluid fistula) and related to the manipulation of arteries (cerebral infarction), brain (cerebral contusion, cerebral inflammation, epileptic seizures) or cranial nerves (facial paralysis, paralysis of other cranial nerves). Any of these complications can lead to a transient or permanent neurological worsening of the patient's symptoms or to the appearance of new symptoms (one-side body paralysis, speech or understanding inability, visual disturbances, superior functions disorders, coma, etc).

There are also complications not directly related to surgery (pulmonary infection, venous thrombosis, embolism, lack of sodium in the blood, anaemia, gastrointestinal bleeding, etc). Finally, it is also possible that some problems are due to the haemorrhage produced by the rupture of the AVM and not to the surgery. Even if the final outcome and complications depend on the patient's condition, for any other unexpected reason postoperative mortality may reach 10% in some cases.

Alternative treatments

The ultimate goal of the treatment of an AVM is its exclusion from the cerebral circulation without directly or indirectly injuring neighbouring areas. With this premise in mind, and along the surgical treatment of AVMs, a series of complementary and alternative techniques have been developed that have substantially modified the treatment strategy. Among them we must fundamentally highlight two: interventional neuroradiology and Radiosurgery.

Today, a modern approach to the treatment of AVMs would not consider taking only one treatment modality into account. The concurrence of these three options has proven to yield the best end results.

Postoperative – Cerebral arteriovenous malformation surgery

The usual postoperative period will depend greatly on the situation of the patient before the operation. After leaving the operating room, the patient will go to the Resuscitation / Intensive Care Unit (ICU) where he will remain at least until the day after the operation.

This aims to make recovery from anaesthesia slow and ideal for a brain that has been recently operated. It also allows a closer monitoring of the patient in the first hours, and the possibility to detect early complications that could require a new intervention.

Once back to the Neurosurgery unit, the patient will be progressively getting up until he finally leaves bed 24 to 48 hours after the intervention. The postoperative period of a head operation of this sort is often not particularly painful. Pain produced in the wound is usually controlled correctly with conventional painkillers. During hospitalisation, the patient will acquire progressive autonomy in his personal care and will start walking around the ward. It is usual to request a cranial CT scan or postoperative control scan and even a new cerebral arteriogram to confirm that the AVM has been completely removed. The patient will be discharged from hospital 7-14 days after surgery, depending on the previous condition and postoperative recovery, providing there are no further complications. After 7-8 days of surgery the stitches will be removed.