The present invention provides a method for positioning an electromagnetic tracking sensor. The method includes attaching a sensor to an anatomy, obtaining an image of the anatomy, indicating a size of each of a plurality of volumes on the image, where the volumes include a smaller and larger volume, and making a determination of whether a region of interest is encompassed by one or more of the volumes. The present invention also provides a system for positioning an electromagnetic tracking sensor. The system includes a sensor attached to a patient anatomy, an imaging modality obtaining an image of the anatomy, an image processor indicating a size of each of a plurality of volumes on the image, where the plurality of volumes includes a smaller and larger volume, and an operator making a determination of whether a region of interest is encompassed by one or more of the volumes.