Home
Health Encyclopedia
Print
Search Clinical Content Search Patient Health Library
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A-Z Listings

Types of Brain Aneurysms

There are several types of brain aneurysms that are classified by shape. These are saccular (also called berry) aneurysms, which are by far the most common. Less common are the fusiform and dissecting types. Brain aneurysms may also be classified by:

  • Size (small, large, and giant)

  • Location

  • Cause (such as a mycotic aneurysm, caused by an infection)

Most aneurysms occur where an artery branches, often at the base of the brain. The risk of an aneurysm bursting (rupturing) can be affected by the shape and location of the aneurysm. The treatment options vary, depending on the type of aneurysm, its size, and its location.

Brain viewed from bottom showing brain stem, cerebellum, and arteries.
Using this picture, the surgeon may mark the site of the aneurysm.

Closeup of brain showing artery with saccular aneurysm.
A saccular (berry) aneurysm bulges from one side of an artery. A neck leads to it.

Closeup of brain showing artery with fusiform aneurysm.
A fusiform aneurysm bulges from all sides of an artery. It rarely has a neck.

Closeup of brain showing giant aneurysm involving two arteries.
A giant aneurysm can affect more than one artery. It's over 2.5 centimeters (cm) wide.

Closeup of brain showing mycotic aneurysm on artery.
A mycotic aneurysm is caused by an infected artery wall. This type of aneurysm is fairly rare.

Online Medical Reviewer: Chris Southard RN
Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Melinda Murray Ratini DO
Date Last Reviewed: 3/1/2024
© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
Powered by Krames by WebMD Ignite
Copyright © The StayWell Company, LLC. except where otherwise noted.

These resources and their content are provided by a third party for informational purposes and do not necessarily reflect the values and positions of Ascension, its ministries, or its subsidiaries.

About StayWell | Terms of Use | Privacy Policy | Disclaimer

The Services may integrate with Third-Party Apps or contain third-party content or provide links to third-party websites. For example, the Services may integrate with Third-Party App providers to provide you with information. You authorize Ascension to transmit information about You to and receive information about You from applicable third parties.
You agree that Ascension is not responsible for Third-Party Apps, third-party content or third-party websites, and does not make any endorsements, representations or warranties regarding the same. Your use thereof is at Your own risk and subject to the third party’s terms and conditions, as applicable. By using a Third-Party App or third-party content or websites, You agree to the applicable third party’s terms and conditions, even if Ascension does not present them to You at the time of Your use.