The most common cause of brainstem hemorrhage is generally hypertension. The mechanism by which hypertension causes bleeding is chronic long-term hypertension, leading to hyaline degeneration of the small arterial walls. Under the force of blood flow, these walls are prone to bulging, leading to the formation of microaneurysms. When blood pressure fluctuates sharply, especially when there is a significant increase, it can cause these microaneurysms to rupture, leading to bleeding. Thus, if there are noticeable symptoms before the hemorrhage, they are mostly due to a sudden increase in blood pressure. Patients often experience dizziness or headaches, sometimes along with blurred vision, and may be accompanied by nausea and vomiting, but most patients may not feel any abnormalities before the bleeding occurs.