Imaging condition determining method and an X-ray CT apparatus

The present invention provides an image forming condition determining method and X-ray CT apparatus, it may facilitate configuration meet the conditions for forming a predetermined helical scan imaging purposes. For helical scan by an X-ray CT imaging to advance the patient is an adult or child care, imaging the lesion, the length of the imaging and the highest priority user-specified imaging conditions are summarized in the table of various parameters extracted from the candidate imaging condition table, patient radiation dose in the imaging condition candidate display; allows the user to adjust the dose; corrected by changing the dose according to the candidate, thereby determining the image forming condition. When there are multiple candidates, it may be determined according to the imaging condition specified by the user of the second priority.