Cerebral vessels

The incidence of undetected cerebrovascular aneurysms in the general population is 2%. Aneurysms are often found incidentally during a magnetic resonance imaging (MRI) of the head, which is done for other reasons – usually to check for headaches or dizziness. Whether an aneurysm found by chance should be treated is always a case-by-case decision. The risk of rupture is weighed against the risk of treatment. The most important factors are the size of the aneurysm, its location, its shape and a hereditary predisposition within the family. The risk of complications in the treatment of non-ruptured aneurysms is about 1.5% in large centers specializing in aneurysm treatment – for both surgery and endovascular therapy. The decision for treatment or just follow-up controls should be discussed and made in a personal consultation with a specialist at an aneurysm center.

The question of the hereditary nature of aneurysms is often raised. Fortunately, only a small proportion of patients have a genetic predisposition and therefore a family history of aneurysms. If there is no familial cluster, regular screening of relatives of a patient with an aneurysmal subarachnoid hemorrhage is not necessary.

The most frequent and at the same time most serious complication of an aneurysm is its rupture, which leads to a subarachnoid hemorrhage. In this case, blood is forced with arterial pressure into the space between the brain and the base of the skull. The typical classic sign of an aneurysm rupture is the sudden onset of a severe headache of an intensity not previously experienced by the patient. After a rupture, the aneurysm should be removed within 1–2 days by endovascular aneurysm closure (coiling) or in a microsurgical operation (clipping). The optimal treatment of aneurysms is one of the main areas of research at the Inselspital.

Arteriovenous malformations (AVMs) are malformations of the blood vessels and consist of a network of short-circuit connections between brain arteries and brain veins. AVMs can vary greatly in size, flow pattern and location in the brain and can cause very different symptoms. The most common symptoms include headaches, epileptic fits and intracerebral hemorrhages. Whether and how to treat an AVM is always a trade-off between the risk of rupture and the risks of treatment. Both scientifically and clinically, AVMs are one of the main areas of focus at Inselspital.

Cavernomas or cavernous malformations are vascular malformations consisting of irregular small vascular chambers surrounded by brain or spinal cord tissue. They have no brain tissue and no large arteries or veins inside. The risk of hemorrhage is relatively small apart from the brainstem. Despite this a cavernoma can cause epilepsy, headaches or even neurological deficits. However, most of these vascular tangles do not cause any symptoms and are only discovered by chance during imaging (MRI). Whether and how a cavernoma should be treated must be decided individually for each patient.

A hemangioblastoma, or angioblastoma for short, is a rare, benign (WHO grade I) and extremely vascular tumor that often has cystic parts in addition to a solid node. Hemangioblastomas are usually localized in the cerebellum, brain stem or spinal cord. Hemangioblastomas are often due to von Hippel-Lindau syndrome (VHL), but can also occur sporadically. Microsurgical removal of an angioblastoma is the first-line treatment. The difficulty of the operation varies depending on the size, location and tumor cyst.

A dural arteriovenous fistula (dAVF) is an acquired pathological connection of arterial vessels and venous blood vessels in the brain. Too much blood is transported through these vessels which can lead to ringing in the ears in milder cases. In severe cases, a backflow into the brain can cause brain hemorrhages, epileptic seizures or brain swelling with tissue destruction.

Carotid stenosis is the narrowing of the carotid artery caused by atherosclerosis. Carotid stenosis is common and is one of the most important triggers for stroke. The aim of treatment is to prevent further strokes and the associated neurological deficits. Two treatment options are possible: surgical removal of the atherosclerotic plaque or endovascular therapy. Which therapy is the right one is decided on an interdisciplinary basis in the neurovascular board and for each patient individually. Treatment requires an experienced team of neurosurgeons, neurologists and neuroradiologists.

A cerebrovascular disease is a condition in which the brain no longer receives an adequate supply of blood. A stroke, for example, is an acute cerebrovascular disease. The causes of such a circulatory disorder are manifold. Treatment usually consists of treating the risk factors or endovascular therapy. For vascular disorders that originate inside the skull and cannot be treated with endovascular therapy, bypass surgery may be considered.

Moyamoya disease is a rare disease of the cerebral vessels in which there is a slowly progressive narrowing of the intracranial carotid artery and its main branches. Patients suffering from the disease are at significant risk of stroke because the blood supply to the brain is usually inadequate or intracerebral hemorrhage may occur. Neurosurgical treatment is the only effective therapy to reduce the risk of recurrent strokes and the associated neurological deficits. An experienced team of neurosurgeons, neuroanesthetists, neurointensivists and neurologists is crucial to the success of treatment.