| 摘要 |
The invention relates to an X-ray imaging unit and method for imaging the jawbone region for providing slice images of the region of interest. The unit includes a carrier element which comprises an X-ray source (20) disposed on one side of the object and a receiving means (21) disposed on the side of the object opposite from the X- ray source for receiving the radiation transmitted through the object for providing projection images. The carrier element is adapted to rotate around its rotation axis such that the X-ray source and the receiving means revolve around the object. The unit is adapted to effect a spinning motion of the carrier element around an object substantially stationary relative to the unit such that, during the spinning motion, the carrier element's rotation axis advances along a path which substantially follows the jawbone anatomy. During said spinning motion, projection images of the jawbone over a limited angular range are produced such that areas inside the jawbone arch remain substantially unexposed to radiation. The unit comprises computing means for working out reconstructed volume models by effecting the computation with at least one angular range reconstruction process on the basis of said projection images of a limited angular range, and computing means for working out the required slice images of the region of interest on the basis of said volume models. |
