Aneurysm coiling

What is aneurysm coiling?

Coiling refers to a minimally invasive treatment option for intracranial aneurysms, which are bulges in arteries within the skull that may lead to life-threatening bleeding.

During the coiling procedure, a fine platinum coil is inserted into the bulge, allowing the blood to clot and seal the aneurysm. Nowadays, most intracranial aneurysms are treated by coiling.

How do aneurysms develop?

Aneurysms can be either congenital or acquired over the course of a lifetime.

Congenital aneurysms usually occur at the base of the brain, however, cquired aneurysms can also develop there. The most common locations for aneurysms to develop after birth are the aorta (main artery) and the arteries of the extremities, in particular in the area of the back of the knee. This is frequently caused by atherosclerosis, as well as disorders affecting the connective tissue like Marfan syndrome or Ehlers-Danlos syndrome. 

Intracranial aneurysms (aneurysms inside the skull) affect around 3% of the population, and the incidence increases with age. Most patients, however, never show any symptoms.

Indication: When is aneurysm coiling suitable?

The decision to treat an aneurysm and which method to use is always an individual case decision. In the process, the risks of the aneurysm must be weighed up against the potential complications associated with its treatment.

In principle, there are two ways that aneurysms in the skull can become symptomatic. Should they compress adjacent nerve cells, such as cranial nerves, damage and loss of the affected nerve can result, which depending on the nerve can be of a sensory, motor or vegetative character.

The most feared complication of an intracranial aneurysm, however, is subarachnoid hemorrhage. If the aneurysm ruptures, blood will escape from the artery into the inside of the skull. Because the bony skull is unable to expand, the brain tissue is consequently squeezed by the inflow of blood. This represents a life-threatening emergency. About half of the survivors are left with neurological or neuropsychiatric deficits.

Thus, aneurysms with a localizations linked to a high probability of rupture as well as a large aneurysms are indications for treatment. If nerves are compressed, treatment is also indicated.

The location and shape of the aneurysm determine if it can be closed by coiling or if it needs to be treated with clips during a neurosurgical operation. Before any treatment is considered, the patient undergoes imaging examinations with an interdisciplinary assessment by neuroradiologists and neurosurgeons. Both therapy options carry risks that need to be carefully balanced against the risk of the aneurysm. The age of the patient, accompanying illnesses and, of course, the patient's preferences must be factored in.

Once the aneurysm has ruptured, it may be necessary to perform a coiling procedure to stop the active bleeding or to prevent secondary bleeding.

Aneurysm coiling: what is the procedure? 

Aneurysm coiling is a minimally invasive operation performed under general anesthesia. 

It involves advancing a thin catheter via a blood vessel, typically the inguinal artery, up to the aneurysm in the cerebral artery. This catheter holds an unwound platinum coil, which rolls up into a ball once placed in the aneurysm. The blood starts to clot around the meshes of this ball, causing the aneurysm to be sealed by a thrombus.

The treatment can be performed in an emergency setting in the event of a ruptured aneurysm, but also as a planned procedure to repair an aneurysm that has become noticeable through nerve compression or as an incidental finding.

Risks & complications

Coiling is associated with all the general risks that any surgical procedure as well as anesthesia entail. Furthermore, there are risks and complications specific to this procedure.

The general risks include

• Infections

• Bleeding

• Injuries to nearby structures

• Risks associated with anesthesia (e.g. injuries to teeth and oral cavity when inserting the breathing tube, circulatory disturbances, ventilation problems)

In the first weeks to months following the procedure, recanalization, a partial reopening of the aneurysm, may occur. This should be identified during a follow-up check and needs to be treated by re-coiling. 

Furthermore, it is possible that a part of the formed blood clot in the aneurysm may break loose and occlude a cerebral vessel, leading to a stroke.

Follow-up care & rehabilitation

One week after the operation and again after six months, an angiography should be performed as a check-up. This is a special imaging study to visualize blood vessels and can be performed using computer tomography (CT) or magnetic resonance imaging (MRI). It is designed to detect any recanalization and allow for its treatment. Recanalization is very unlikely after six months.

MRI examinations of the skull at intervals of several years should also be carried out throughout the patient's entire lifetime in order to identify potential second aneurysms, since the risk in patients who have already had an aneurysm is significantly higher than in the normal population.

Once the patient has been discharged from the hospital, follow-up treatment (rehabilitation) can be carried out, which is strongly recommended, particularly in the case of a subarachnoid hemorrhage. After coiling, patients should refrain from physical exercise for several weeks to avoid spikes in blood pressure. There are no special long-term precautions for patients.

Which doctors and clinics specialize in aneurysm coiling?

An intracranial aneurysm must always be assessed by neuroradiologists and neurosurgeons from an interdisciplinary perspective to ensure that an optimal treatment plan can be worked out. If patients and doctors opt for treatment by coiling, this should be carried out by a neuroradiology department that has the appropriate expertise.

If you're in need of a doctor, you expect the best medical care possible. So of course patients are curious to find out what clinic to go to. As there is no objective way to answer this question and a legitimate doctor would never claim to be the best, patients must rely on a doctor's experience.

Let us help you find an expert for your condition. All listed doctors and clinics have been reviewed by us for their outstanding specialization in the field of aneurysm coiling and are looking forward to your inquiry or wish for treatment.

Sources: 

• Steinmetz et al.: S1-Leitlinie Unrupturierte intrakranielle Aneurysmen. Deutsche Gesellschaft für Neurologie (DGN). Stand: 2012  &

• Steiner et al.: European Stroke Organization guidelines for the management of intracranial aneurysms and subarachnoid haemorrhage. In: Cerebrovascular Diseases. Band: 35, Nummer: 2, 2013 

• flexikon.doccheck.com/de/Coiling&;

• www.amboss.com/de/wissen/Subarachnoidalblutung/&;

• www.uniklinik-duesseldorf.de/patienten-besucher/klinikeninstitutezentren/institut-fuer-diagnostische-und-interventionelle-radiologie/neuroradiologie/interventionelle-neuroradiologie/aneurysma-coiling