Definition: The term "arteriostenosis" refers to a condition characterized by an abnormal dilation or narrowing of small arteries. It can lead to increased blood pressure, which could cause symptoms like severe headache, neck stiffness, and difficulty breathing. Specifically, it occurs when there are too many blood vessels in one artery, leading to a blockage that causes the blood flow to be blocked. This can result in serious health issues, such as heart attacks or strokes.