PROBLEM TO BE SOLVED: To easily apply a fluid structure analysis result to an abnormality diagnosis of a blood vessel.SOLUTION: An injection profile acquisition unit acquires an injection profile of contrast media injected into a blood vessel of a subject, and a time-series CT value acquisition unit acquires a time-series CT value in the intravascular lumen after the injection of the contrast media. Further, a fluid structure analysis unit performs fluid structure analysis simulation, with the injection profile and the time-series CT value used as inputs. A first calculation unit calculates a nominal model representing a relationship between the input and output same as the fluid structure analysis simulation on the basis of the result performing the fluid structure analysis simulation using the injection profile and the time-series CT value, where abnormality/normality of the blood vessel has been determined, and stores the nominal model in a storage device. A difference model calculation unit detects difference between the time-series CT value of the subject whose blood vessel is subjected to the abnormality diagnosis, and the nominal model stored in the storage device, and calculates a difference model representing a degree of the abnormality of the blood vessel. A diagnosis unit evaluates the difference model and diagnoses the abnormality of the blood vessel.
