Intracranial Venous Malformations – Symptoms and Causes
Overview
Intracranial venous malformations are enlarged veins within the brain. These larger blood vessels typically function normally despite their unusual size. Many people live with these malformations without experiencing any symptoms or knowing they exist.
Healthcare providers often discover these venous abnormalities accidentally during brain imaging tests performed for unrelated conditions. Since these malformations rarely cause problems, they typically don’t need treatment. Regular monitoring may be all that’s necessary in most cases.
Signs and Symptoms
People with brain vein malformations often have no symptoms. These abnormal connections between veins in the brain may be found by accident during brain tests for other reasons.
However, when symptoms do appear, they can vary based on the location and size of the malformation.
Common symptoms include:
- Headaches that may feel different from regular headaches
- Seizures or sudden jerking movements
- Weakness or numbness in parts of the body
- Vision problems such as blurred or double vision
- Speech difficulties
- Balance or coordination problems
- Confusion or memory issues
Sometimes, a brain vein malformation may bleed. This is called a hemorrhage and can cause sudden, severe symptoms such as:
- Very intense headache that comes on suddenly
- Nausea and vomiting
- Stiff neck
- Sensitivity to light
- Reduced alertness or consciousness
When to Contact a Healthcare Provider
Contact your doctor if your existing symptoms worsen or new symptoms develop.
Seek immediate medical help if you experience:
- A sudden, severe headache unlike any you’ve had before
- Weakness or numbness on one side of your body
- Trouble speaking or understanding speech
- Vision problems that come on suddenly
- Seizures, especially if you’ve never had one before
Early detection and proper management can help prevent serious complications and improve outcomes.
Causes
Brain venous malformations happen when blood vessels don’t form correctly during fetal development. These tangles of abnormal blood vessels occur when veins that normally drain blood from the brain develop incorrectly. Scientists don’t fully understand why these malformations form.
Most venous malformations are present at birth (congenital). They aren’t typically passed from parents to children, meaning they usually occur sporadically. In rare cases, they may develop later in life due to trauma or other medical conditions.
Environmental factors during pregnancy might contribute to their formation. These could include:
- Maternal infections
- Exposure to certain medications
- Radiation exposure
- Nutritional deficiencies
Venous malformations often coexist with other types of vascular abnormalities in the brain. About 25% of people with venous malformations also have cavernous malformations, which are clusters of abnormal blood vessels with thin walls.
Risk Factors
Several factors may increase a person’s chances of developing intracranial venous malformations. These abnormal blood vessel formations in the brain can sometimes run in families, suggesting a genetic component.
Research shows that about 20% of people with these malformations have at least one family member with the same condition.
Age plays a significant role in risk assessment. While these malformations are present from birth, symptoms often don’t appear until adulthood, typically between ages 20-40. However, they can be discovered at any age when imaging is done for other reasons.
Genetic factors play a role in some cases. Genetic conditions associated with higher risk include:
- Hereditary Hemorrhagic Telangiectasia (HHT)
- RASA1 gene mutations
- Sturge-Weber syndrome
Environmental factors might contribute to the development or triggering of symptoms. Brain trauma, infections, and certain medications that affect blood clotting can potentially increase risks in those with underlying malformations.
Gender differences exist in how these conditions manifest. Pregnancy can affect existing venous malformations due to hormonal changes and increased blood volume.
The presence of other vascular abnormalities in the brain increases the likelihood of having venous malformations. About 15% of patients have multiple types of vascular issues occurring together.
