Arteriovenous Malformation

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What is Arteriovenous Malformation?

Arteriovenous malformations (AVMs) are defects of the circulatory system that are generally believed to arise during embryonic or fetal development or soon after birth.  Although AVMs can develop in many different sites, those located in the brain or spinal cord can have especially widespread effects on the body.  Most people with neurological AVMs experience few, if any, significant symptoms.  The malformations tend to be discovered only incidentally, usually either at autopsy or during treatment for an unrelated disorder

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Histopathologically Imaging :
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Angiography Imaging:
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 MRI Imaging:
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Is there any treatment?

Medication can often alleviate general symptoms such as headache, back pain, and seizures caused by AVMs and other vascular lesions. However, the definitive treatment for AVMs is either surgery or focused irradiation therapy.  The decision to perform surgery on any individual with an AVM requires a careful consideration of possible benefits versus risks.

Treatment may include:
  • Surgical removal (resection). In this procedure, your neurosurgeon removes a section of your skull temporarily to view your AVM through a high-powered microscope. Your surgeon seals off the AVM using special clips or a laser and uses small cautery tools to carefully remove the AVM from surrounding brain tissue. Your surgeon then reattaches the skull bone and closes the incision in your scalp.
    Sometimes your surgeon may perform this procedure while you are awake (awake brain surgery). Your responses to questions during the procedure help your surgeon avoid injuring areas of your brain that control speech or movement.
    Usually, while you're under general anesthesia, your doctor will order an angiogram to ensure the AVM is completely gone. If any of the AVM remains, you may immediately return to the operating room for further surgery.
  • Stereotactic radiosurgery. Stereotactic radiosurgery uses precisely focused radiation to destroy your AVM. In this procedure, the radiation causes the AVM blood vessels to slowly close in one to three years after treatment. You won't need general anesthesia or an incision. Stereotactic radiosurgery may be an option if you have a small arteriovenous malformation that hasn't caused a life-threatening hemorrhage.
  • Endovascular embolization. In this procedure, a doctor inserts a long thin tube (catheter) into an artery in your leg and threads it through blood vessels to your brain using X-ray imaging. Your surgeon places the catheter in one of the arteries that feeds your AVM and injects small particles or a gluelike substance to block the artery and reduce blood flow into the AVM.
    Often, surgeons perform embolization before surgery to reduce the chance of bleeding during the operation, or to reduce the size of the AVM so stereotactic radiosurgery or conventional surgery can be more effective. If you have a large AVM that appears inoperable, embolization may reduce your symptoms by redirecting blood back to the normal brain tissue.

What is the prognosis?

The greatest potential danger posed by AVMs is hemorrhage. Researchers believe that each year between 2 and 4 percent of all AVMs hemorrhage. Most episodes of bleeding remain undetected at the time they occur because they are not severe enough to cause significant neurological damage. But massive, even fatal, bleeding episodes do occur. Whenever an AVM is detected, the individual should be carefully and consistently monitored for any signs of instability that may indicate an increased risk of hemorrhage.

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