Apparatus and methods are described including an endoluminal device configured to move along a portion of a lumen of a subject's body, an extraluminal imaging device, and at least one computer processor. While the endoluminal device moves along the portion of the lumen, a display displays an extraluminal image of the lumen in which a first indication of a location of the lumen is shown. The extraluminal imaging device acquires a sequence of extraluminal images of the endoluminal device moving along the portion of the lumen. The indication of the location of the lumen that is displayed is updated based upon the acquired sequence of extraluminal images, and the acquired sequence of images is displayed with the updated indication of the location of the lumen overlaid upon the images. Other applications are also described.