Digital tomography: description and preliminary clinical experience

Digital tomography was performed in 30 patients using a new prototype system with a PET-Scope image tube. Twenty-eight exposures are obtained during a single revolution of the x-ray source over the volume of tissue to be imaged. The sum of the radiation produced by the 28 exposures is about equivalent to a single routine exposure of the part imaged. The data accumulated can provide up to 200 tomographic sections at intervals of 5 mm. Reconstruction time for each section is 3 sec. The raw images may be reconstructed as often as desired. Algorithms are being developed to allow axial and sagittal reformations. Further work is required to improve spatial resolution and contrast and to develop algorithms to allow subtraction of blurred images above and below the reconstructed site. The authors believe that digital tomography may eventually replace most routine tomograms.