Headache and intracranial murmur, beware of dural arteriovenous fistula!

Author: Jiang Chuhan, Chief Physician, Beijing Tiantan Hospital, Capital Medical University

Reviewer: Xu Jun, Chief Physician, Beijing Tiantan Hospital, Capital Medical University

Human blood vessels are divided into arteries and veins. Arteries supply nutrients and oxygen to organs and tissues throughout the body. After supplying tissues, they also collect return blood through veins and drain it to the heart, forming a loop.

Dural arteriovenous fistula is a lesion in which the arteries and veins on the dura mater are directly connected, commonly known as a short circuit. The blood from the arteries goes directly into the veins without supplying the corresponding dura mater tissue.

Based on current research, the cause of dural arteriovenous fistula is still unclear, but most experts believe that it is acquired.

First, we have found in clinical practice that many patients with venous sinus thrombosis have concurrent dural arteriovenous fistula, or among patients with dural arteriovenous fistula, many have venous sinus thrombosis. Therefore, we believe that venous sinus thrombosis may be a cause of the formation of dural arteriovenous fistula.

Second, some patients with dural arteriovenous fistula have a history of brain trauma, so brain trauma may also be a cause.

Third, women with amenorrhea are also prone to dural arteriovenous fistula, especially dural arteriovenous fistula in the cavernous sinus area, so it may be related to the decrease in estrogen levels.

Fourth, the hypercoagulable state of the blood may also be some of its causes. Studies have suggested that dural arteriovenous fistula is related to gene mutations that cause hypercoagulable state.

In addition, dural venous fistula in children is a rare congenital venous sinus developmental abnormality.

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The symptoms of dural arteriovenous fistula are very complex and varied, mainly due to the different drainage veins and locations, which cause different symptoms. Some symptoms are very mild, while others are very severe.

Depending on the symptoms caused by the drainage veins, for example, in mild cases, there are only intracranial murmurs and headaches. As the cortical venous drainage increases, blurred vision, intellectual disability, unstable gait, and bedriddenness may occur, and finally life-threatening conditions may occur. The symptoms are very extensive.

For example, in the cavernous sinus area, patients mainly suffer from intracranial murmurs, bulging eyes and red eyes; for example, dural arteriovenous fistulas in the cerebellar tentorium area and the anterior cranial fossa floor can cause cerebral hemorrhage, and patients will suddenly have headaches and coma, and the symptoms are very serious; dural arteriovenous fistulas in the foramen magnum area may drain to the spinal cord, and patients will have spinal symptoms such as lower limb movement disorders as the first manifestation.

Generally speaking, common symptoms of dural arteriovenous fistula include headache, intracranial murmur, etc. Among them, intracranial murmur is a kind of blowing murmur, which is a "whooshing" sound that the patient can hear.

The diagnosis of dural arteriovenous fistula mainly relies on two aspects: clinical symptoms and imaging examination.

The clinical symptoms include headache, intracranial murmur, bulging eyes, etc. After these symptoms appear, you should go to the hospital for examination.

Imaging examinations can include CT scans, which can detect bleeding and abnormalities in the drainage veins of the eye. MRI scans can also detect abnormal drainage veins. We can also perform some non-invasive imaging tests, such as MRA (magnetic resonance angiography) or CTA (CT angiography), which can directly detect the presence of dural arteriovenous fistulas.

After these non-invasive examinations discover or suggest dural arteriovenous fistula, we still need to do an invasive DSA, i.e. cerebral angiography, to confirm the dural arteriovenous fistula, which is the gold standard for diagnosing dural arteriovenous fistula.

In addition to confirming the diagnosis, during the angiography examination, it is also necessary to observe its blood supply arteries and drainage veins to provide a basis for formulating the next treatment plan.

There are three treatment methods for dural arteriovenous fistula: conservative treatment, interventional treatment, surgery and gamma knife-assisted treatment.

Through appropriate treatment, most dural arteriovenous fistulas can be completely cured. Now with the development of materials, its cure rate is very high, and the anatomical cure rate is over 80%.

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What is anatomical cure? It means that we have completely cured the lesion, and various imaging examinations cannot detect the lesion. This is called anatomical cure.

The opposite of anatomical cure is clinical cure. Currently, the clinical cure rate of dural arteriovenous fistula is over 90%.

What is clinical cure? Clinical cure means that although there is still lesion and fistula can be found in angiography, there are no clinical symptoms, such as red eyes and intracranial murmurs. This is called clinical cure.

Therefore, the treatment effect of dural arteriovenous fistula is still very good.