Abstract
We must introduce risk management for prevention of medical accidents in clinical examination. It is a useful method for prevention of patient's harm or injury to investigate and analyze various risk cases in many facilities. Though the main cause of medical troubles depend on medical accidents, unexpected incidents, and others, it is also useful for prevention of medical trouble to respond to patient's questions and complaints. So, we investigate and analyze various risk cases in the department of radiology. In this paper, we discuss medical troubles due to patient's question and complaint.