Abstract: A method and system are presented for enhancing one or more images of an object, so as to increase the visibility within the images of one or more structures within the object. The object may be an anatomical region of a patient, and may include one or more reference structures, for example skeletal structures or vertebral structures, and one or more treatment targets, for example tumors or lesions. An operator, for example a top-hat filter operator, selects at least a first neighborhood and a second neighborhood within the images. The operator selects within each neighborhood one or more pixels having an optimal pixel value, and eliminates the remaining pixels in these neighborhoods. When the operator is applied to the selected neighborhoods, only the pixels having the greatest pixel values remain in the selected neighborhoods, and the remaining pixels are eliminated in the selected neighborhoods. As a result, desired features can be located and enhanced in the images.