| 摘要 |
Apparatus and methods are described including acquiring a first set of extraluminal images of a lumen, using an extraluminal imaging device. At least one of the first set of images is designated as a roadmap image. While an endoluminal device is being moved through the lumen, a second set of extraluminal images is acquired. A plurality of features that are visible within images belonging to the second set of extraluminal images are identified. In response to the identified features in the images belonging to the second set of extraluminal images, a plurality of local calibration factors associated with respective portions of the roadmap image are determined. Other applications are also described. |
