What is blood vessel dissection? can that cause brain aneurysms

Tearing: Arterial wall has several layers. A dissection is a tear- separation of the layers by blood under pressure usually. Several collagen vascular disorders and hypertension can be involved. Occasionally with trauma or surgical or interventional trauma. Unusual for brain aneurysm but not uncommon with thoracic dissection.

Yes: While most brain aneurysms are of the saccular type (see picture), dissections of the arteries supplying the brain do occur, and these can sometimes form what are called "pseudoaneurysms." dissections can cause hemorrhage, just like a saccular aneurysm, shower debris, or even occlude a vessel, causing a stroke. These can often be very challenging to treat.

Arterial dissection : Can result in a stroke in the distribution of the specific blood vessel, and could be profound if involving the carotid or vertebral. No relationship to aneurysms.

Tear: Dissection is a tear in the blood vessel wall. It can lead to a closure of the blood vessel, formation of blood clots, stroke or formation of a pseudoaneurysm (which is not a true aneurysm, but still should be followed over time). It can, though, be quite benign and have no complications. Please seek advice from your neurologist if you have a history of dissection.