What type of aneurysm is small and may rupture, leading to a subarachnoid hemorrhage?

The type of aneurysm that is small and can rupture, potentially causing a subarachnoid hemorrhage, is a berry aneurysm. Berry aneurysms are typically found on the branches of the arteries at the base of the brain, particularly in the circle of Willis. They are small, round outpouchings that often appear like a berry on a stem, which is how they got their name.

The primary concern with berry aneurysms is their propensity to rupture, which can lead to a subarachnoid hemorrhage—a serious condition characterized by bleeding into the space surrounding the brain. This type of hemorrhage can cause sudden and severe headaches, neurological deficits, and can be life-threatening.

Other types of aneurysms mentioned, such as fusiform and dissecting aneurysms, typically involve larger, more extensive vascular structures and have different characteristics and risks associated with them. Fusiform aneurysms, for example, involve a more gradual bulging of the vessel wall along a segment of the artery, and while they can rupture, they are not specifically linked to small ruptures leading to subarachnoid hemorrhage. Dissecting aneurysms involve a tear in the artery wall which can lead to serious complications but do not