Neurovascular Diseases - Specialists and Information

Neurovascular diseases are complex disorders of the blood vessel system of the brain and spinal cord. In this medical term, “neuro” refers to the brain and spinal cord, and “vascular” refers to the blood vessel system.

There are both acute and chronic forms. Since the brain is highly sensitive to all types of damage, these are often time-sensitive conditions. They usually require prompt action.

In general, the following conditions belong to the group of neurovascular diseases:

• Vascular bulges (aneurysms)
• Cavernous malformations
• Arterio-venous fistulas
• Vascular narrowing (stenoses and occlusions)

What is unique about bulges in blood vessels (aneurysms)?

Aneurysms that occur in the arteries of the brain (cerebral arteries) are called cerebral aneurysms @ p6m5 /AdobeStock

Aneurysms are bubble- or ball-like dilations of blood vessels that cause life-threatening bleeding when they rupture.

Rupture is the medical term for the bursting of hollow organs and blood vessels. High blood pressure, especially hypertensive crises, is a risk factor for rupture.

In principle, aneurysms can affect any blood vessel, but they most commonly affect the arteries. When arteries in the brain are involved, they are also called cerebral aneurysms. Venous aneurysms are much rarer, and rupture is an exception.

What are cavernomas?

A cavernoma is a sponge-like vascular formation that can occur in the brain and spinal cord. Strictly speaking, it is a benign tumor of the blood vessels. It involves the formation of numerous nodular structures and chambers.

This explains the medical terms “cavernoma” (cavern = chamber) and “cavernous hemangioma” (hem = blood; angioma = benign vascular tumor).

Rupture of cavernomas is a rare complication. Cavernomas are much rarer than aneurysms and are classified as arteriovenous malformations (AVMs). This is an umbrella term for all vascular malformations in which structures known as “arteriovenous tangles” form.

Cavernomas are vascular malformations that are often first noticed due to seizures @ Naeblys /AdobeStock

What are dural arteriovenous fistulas?

Arteriovenous fistulas (AVFs) are generally defined as shunts between the high-pressure and low-pressure systems.

The high-pressure system consists of the arteries, while the low-pressure system consists of the veins. Blood flows directly from the arteries into the veins through the fistula. 

This leads to circulatory disturbances in the downstream tissues. Dural AVFs are specific vascular malformations in the brain and spinal cord, though they are very rare.

What are vascular occlusions in the brain?

Vascular occlusions in the brain can result from narrowings or displaced clots. The primary cause is usually an event such as a stroke. Depending on the size of the occluded vessel, this can cause minimal impairment or trigger serious complications.

Clots form particularly in cases of cardiac arrhythmias, while narrowings are most often caused by calcification of the vessel walls (medically known as atherosclerosis).

Comparison of a healthy artery, an artery with impaired blood flow, and an artery with disrupted blood flow @ Axel Kock /AdobeStock

The various diseases of the nervous system are associated with different symptoms. For example, an aneurysm is primarily characterized by a severe headache.

The following symptoms are typical of a stroke:

• Vision problems
• Dizziness
• Gait, balance, and coordination problems
• Numbness or weakness, usually on one side of the body—in the arms, legs, or face
• Speech difficulties

An arteriovenous malformation (AVM) is characterized by

• Symptoms of a brain hemorrhage
• Headache
• Tinnitus
• Seizures or
• stroke-like symptoms

When cavernomas cause symptoms, they often involve bleeding and seizures.

The most common type of neurovascular disease is a stroke, also known as a cerebral infarction. A stroke results in poor blood flow to the brain tissue. This can be caused by a blockage or narrowing of the blood vessels.

The risk of stroke increases due to:

• Diabetes
• High blood pressure
• Lack of exercise and obesity
• Stress
• Smoking
• Heart disease
• advancing age and
• Genetic predisposition

Aneurysms usually occur sporadically. The opposite of sporadic is a family history of aneurysms, which, however, is less common.

Approximately 5 percent of people have a brain aneurysm. Of these, 30 percent of patients have aneurysms in multiple locations.

Of particular note here are the aorta and the popliteal artery. Occasionally, aneurysms occur as a complication of polycystic kidney disease.

For many neurovascular disorders, the symptoms described above already provide important clues about the nature of the disease. These are identified during the medical history interview through targeted questions. Physicians must also consider a family history of the condition to support their suspicion.

An aneurysm can be detected through a specialized screening and is thus, in some cases, an incidental finding. This aneurysm screening is recommended if two first-degree relatives have this condition.

MR angiography (magnetic resonance angiography) is a specialized form of magnetic resonance imaging (MRI). This imaging technique visualizes the blood vessels and helps identify neurovascular disorders.

Cavernomas can also be clearly and reliably visualized during MRI examinations. In cases of strong suspicion, MR angiography is usually the diagnostic method of choice.

MRI is also used in cases of strokes and associated vascular occlusions. An important alternative to MRI is computed tomography (CT), which also delivers the best results when contrast agents are used.

When contrast agents are used, medical professionals refer to the procedure as CT angiography (CTA). However, the contrast agent used in CTA has more side effects than that used in MRA. It can lead to kidney problems and allergic reactions.

Who treats neurovascular diseases?

For many neurovascular diseases, surgery is required to remove the underlying cause or correct the vascular abnormalities. However, there are numerous different treatment options, which depend on the severity of the disease.

The medical specialty that deals with diseases of the vascular system in the brain is vascular neurosurgery. Since this involves the treatment of highly complex conditions, several medical specialties should work together.

These include:

• Neurosurgery
• Neurology
• Neuroradiology
• Vascular surgery
• Radiation therapy and
• Pain Management

When children suffer from neurovascular disorders, pediatric neurosurgery (neurosurgery for children) must be involved. This department serves as the point of contact for surgical treatment and psychological care.

Narrowed blood vessels (stenoses) can be kept open using a stent—specifically, a metal or plastic vascular support. This is a widely used method, particularly in cases of stroke.

If a patient has a vascular bulge (aneurysm), doctors make decisions on a case-by-case basis depending on its size and rate of growth. 

A widely used treatment method is endovascular coiling. In this procedure, doctors insert metal coils through a catheter and deploy them at the site. The goal is to cut off the blood supply to the aneurysm. This reduces the risk of a life-threatening rupture.

In some cases, coiling is not successful or is not suitable. Therefore, open-surgery to treat aneurysms is sometimes used. However, this requires general anesthesia and the opening of the skull. Endovascular therapy, on the other hand, is performed under local anesthesia.

For an AVM, microsurgical intervention may be considered, with the goal of keeping the surgical procedure as minimally invasive as possible. 

Microsurgical procedures are the preferred treatment, particularly for AV fistulas. The skull or spinal canal is accessed through small incisions to minimize surgical trauma as much as possible. 

Endovascular methods are also available and yield similarly good results.

The most serious complication of neurovascular surgery is damage to nerve tissue. Therefore, a clear view of the surgical site in the brain or spinal canal is of utmost importance. This is why specialized surgical microscopes are used.

Neuromonitoring, for example, uses acoustic and optical stimuli to safely monitor nerves. This minimizes the risk of injury to the nervous system during surgery.

The success of treatment for neurovascular diseases depends on many factors, such as:

• How old is the patient?
• How early is treatment initiated?
• And what type of neurovascular disease is it?

In the case of strokes, aneurysms, and similar conditions, the timing of treatment is critical. 

These conditions are medical emergencies in which every second counts. If you experience any of these symptoms, do not hesitate to call an ambulance to ensure the best possible outcome.