Surgery to remove a brain aneurysm

A pathological bulge in the wall of a cerebral artery is virtually impossible to excise, and in neurosurgery, brain aneurysm surgery means treating it surgically by clamping (clipping) the aneurysm, its endovascular embolization and stenting. [1]

Indications for the procedure

Surgical intervention is indicated for arterial aneurysms of the cerebral and internal carotid arteries in cases of increased deformation of the arterial wall, increased neurologic symptoms, aneurysm rupture or its high risk.

At the same time, the term of surgery and its type are determined by the presence/absence of vasospasm, cerebral edema, hematoma, hydrocephalus and hemorrhage into the subarachnoid space - subarachnoid hemorrhage, the clinical severity of which and prognostic survival of patients are assessed by the Hunt&Hess scale (Hunt&Hess or H-H). The maximum survival rate in patients with 1-2-3 degrees of severity (70%, 60% and 50%, respectively), so the success rate of surgery is quite high.

If patients have the 4th degree (stupor, incomplete paralysis or increased tone of all muscles - decerebration rigidity, as well as dysfunctions of the autonomic nervous system), the survival rate is estimated at 20%. And in comatose state (5th degree of severity) there is an increasing hypoxia of brain tissue, and the probability of survival does not exceed 10%. In such cases, intervention is possible only after the patient has emerged from stupor/coma.

Read also - Operations for arterial aneurysms and arteriovenous malformations of the brain

Preparation

If surgery for a brain aneurysm is performed as an emergency, the preparation is:

• digital subtractive angiography of the brain;
• ultrasound transcranial doppler ultrasonography of cerebral vessels;
• computed tomography (CT) or magnetic resonance imaging (MRI) of the brain and its blood vessels.

If an aneurysm is detected before the operation becomes urgent, it is necessary to undergo the above-mentioned instrumental diagnostics and take: blood tests (general, for platelets and fibrinogen, for thrombin and prothrombin time) and analysis of liquor.

Several days before the procedure, any medications, including Aspirin and NSAIDs (non-steroidal anti-inflammatory drugs), should be discontinued; the patient should not eat or drink anything eight hours before the procedure. The anesthesiologist also determines the anesthetic agent beforehand.

Technique Surgery to remove a brain aneurysm

The methods used by neurosurgeons depend on the localization, size and shape of the aneurysm (sac or spindle), also taking into account the severity of the patient's condition, his age and general history.

Surgical clipping of a brain aneurysm is traditional and requires exposing the skull bone and making a hole in it, i.e. A bone-plasty craniotomy (trepanation) on the scalp and open brain surgery using microsurgical techniques. Once the affected vessel is accessed, the neck of the aneurysm is clamped - using a tiny titanium clip - and isolated from the artery, cutting off blood flow to it and thus preventing further growth or rupture of the abnormal bulge in the vessel wall.

The trepanation site is closed with the removed bone and soft tissue flaps and fixed with sutures and dressing.

Intravascular or endovascular cerebral aneurysm surgery - minimally invasive placement of a spiral inside an artery - is a more recent method of treating cerebral aneurysms; it is also called endovascular spiralization, and foreign specialists call it coiling. This procedure, without violating the integrity of the skull, allows blocking the blood flow into the cerebral aneurysm and preventing its rupture. [2]

The technique consists in the introduction of a guide catheter into the femoral artery (through a puncture of the skin and vessel wall in the groin area) and a microcatheter, which is advanced upwards under the control of radiological visualization to reach the cerebral artery where the aneurysm is localized. The catheter is brought to the area of the aneurysm and a microscopic spiral (platinum or platinum-coated) is released through its mouth, which causes thrombus formation and occlusion of the aneurysm. This procedure is therefore defined as endovascular embolization or endovascular occlusion of cerebral aneurysms.

Mesh metal stents are used to keep the spirals inside the aneurysm - opened with a balloon or self-expanding while stenting the affected artery, meaning the procedure can be a one-stage procedure.

Brain aneurysm stenting is an endoluminal (intraluminal) procedure, the technique of which is similar to endovascular embolization and is also performed under general anesthesia.

In cases of spindle-shaped aneurysms, stent placement can ensure complete occlusion of the aneurysm and preserve patency of the main vessel. FD (flow diverter) stents are used for large aneurysms and wide necks, which restore the diseased artery and block blood flow to the aneurysm due to the formation of a fibrous barrier.

Endovascular occlusion (endovascular spiralization) and stenting of cerebral aneurysms can be performed in two stages: first, a stent is placed, which grows to the vascular wall in 6-12 weeks (its endothelization process takes place), and then the spiral is implanted inside the vessel. [3]

Contraindications to the procedure

Contraindications to surgery for cerebral arterial aneurysms are: acute period with edema and progressive cerebral hypoxia - ischemic stroke; cerebral artery thrombosis; lack of consciousness (stupor) or comatose state of the patient; period of exacerbation of chronic somatic diseases; acute infections; pregnancy.

Consequences after the procedure

Brain aneurysm surgery can have consequences and complications such as:

• bruising, hematoma, and bleeding associated with blood vessel injury;
• thrombosis and thromboembolism (with impaired oxygen supply to tissues);
• cerebral vasospasm - narrowing of the lumen of cerebral arteries;
• cerebral edema;
• hydrocephalus;
• ischemic stroke;
• Development of infection (including bone flap);
• seizures;
• dizziness, confusion;
• damage to cranial nerves with the development of focal neurological symptoms (problems with coordination, vision, speech, memory, etc.).

The most frequent consequences after cerebral aneurysm embolization are associated with vessel perforation; stent migration; iatrogenic (intraprocedural) rupture of the aneurysm - stent, spiral, guide catheter or microcatheter; thromboembolism (including stent thrombosis) and ischemic complications.

Large cerebral aneurysms (as well as giant wide-neck saccular aneurysms) can sometimes recur after the endovascular spiralization technique.

Care after the procedure

After the clipping operation (which can last from three to five hours), patients stay in the intensive care unit for the first time - with constant electrophysiologic monitoring and appropriate medical care. Full recovery from skull fracture and open brain surgery takes an average of three to six weeks, but in the case of aneurysm bleeding, it can take three months or more.

If endovascular embolization of the aneurysm was performed and there was no cerebral hemorrhage before surgery, the hospital stay may last only a few days; if there are complications, inpatient treatment may be prolonged.

After stent implantation, long-term antiaggregant therapy is required: patients are prescribed aspirin (200 mg per day) and platelet aggregation inhibitor Clopidogrel (75 mg per day) for 3 months.

Headaches that occur after aneurysm spiralization in half of the patients usually resolve after a few days. However, in cases of ruptured aneurysms, mild nausea and subfebrile fever may occur after the procedure, and headaches may last up to six months. Paracetomol and other NSAIDs are taken to relieve these.

How long recovery and rehabilitation after brain aneurysm surgery lasts depends on the patient and the degree of brain damage, the presence or absence of aneurysm rupture and bleeding. And the duration of this period varies from two weeks to several months. And in the first two to three weeks, physical activity should be limited as much as possible.

Life after cerebral aneurysm embolization requires a number of changes, in particular: you should stop smoking, follow a balanced diet with a reduction in fat intake and an increase in the proportion of whole-grain products, fresh vegetables and fruits in the diet. And be sure to take measures to reduce high BP.