Ultrasonic diagnostic apparatus

An ultrasonic diagnostic apparatus comprising

• processing circuitry configured to:
• acquire position information relating to an ultrasonic probe and an ultrasonic image;
• acquire ultrasonic image data which is obtained by transmission and reception of ultrasonic waves from the ultrasonic probe at a position where the position information is acquired, the ultrasonic image data being associated with the position information;
• execute associating between a first coordinate system relating to the position information and a second coordinate system relating to medical image data;
• when a positional displacement has occurred after executing the associating between the first coordinate system and the second coordinate system, correct the positional displacement by prompting a user to determine corresponding points or corresponding regions between at least one of the ultrasonic image and the medical image based on the medical image data;
• determine region information which serves as a reference for image alignment, in at least one of an ultrasonic image based on the first coordinate system and a medical image based on the second coordinate system;
• and
• execute image alignment between the ultrasonic image and the medical image which are corrected the positional displacement.