Rupture of Berry aneurysm causes
**Core Concept**
Berry aneurysms, also known as saccular aneurysms, are small, rounded outpouchings of the blood vessel wall that are prone to rupture. They are most commonly found at arterial bifurcations in the circle of Willis at the base of the brain.
**Why the Correct Answer is Right**
Rupture of a Berry aneurysm leads to subarachnoid hemorrhage (SAH), a type of intracranial hemorrhage. The aneurysm wall is under increased pressure due to the turbulent blood flow at the bifurcation, causing it to weaken and eventually rupture. When the aneurysm ruptures, blood is released into the subarachnoid space, the area between the brain and the tissue that covers it, leading to SAH.
**Why Each Wrong Option is Incorrect**
**Option A:** Thrombosis. Thrombosis refers to the formation of a blood clot within a blood vessel. While thrombosis can occur in aneurysms, it is not a direct result of rupture.
**Option B:** Dissection. Dissection refers to a tear in the blood vessel wall, which can lead to hemorrhage. However, dissection is not the primary mechanism of rupture in Berry aneurysms.
**Option C:** Infarction. Infarction refers to tissue death due to a lack of blood flow. Infarction is not a direct result of Berry aneurysm rupture.
**Clinical Pearl / High-Yield Fact**
The Hunt and Hess scale is a grading system used to assess the severity of subarachnoid hemorrhage due to aneurysm rupture, taking into account the patient's clinical presentation and symptoms.
**Correct Answer:** D. Subarachnoid hemorrhage.