1. Computer-implemented method for creating a model from a number of medical image datasets, comprising: providing a number of medical image datasets, the medical image datasets being acquired or having been acquired from same or from different modalities; automatically creating contour lines in the medical image datasets provided; providing a representation; semi-automatically fitting the created contour lines into the representation provided, and merging the provided medical image datasets to create the model for the medical image datasets; and displaying the created model for the medical image datasets.