Dual kVp material decomposition using flat-panel detectors

In addition to a conventional Computed Tomography (CT) image, dual energy (dual kVp) imaging can be used to generate an image of the same anatomy that represents the equivalent density of a particular material, for example, calcium, iodine, water, etc. This image can be used to improve the differentiation of materials as well as improve the accuracy of absolute density measurements in a cross-sectional image. It is important to understand the certainty of the estimation of the density of the material. Both simulations and measurements are used to quantify these errors. Data are acquired using a flat-panel based volumetric CT system, by taking two scans and adjusting the maximum energy of the source spectrum (kVp). Physics based simulations are used to compare with the measurements. After validating the simulation algorithms, the accuracy of the dual kVp method is determined using the simulations in a perturbation study.

[1]  Dual energy iodine contrast CT with monochromatic X-rays , 1995, 1995 IEEE Nuclear Science Symposium and Medical Imaging Conference Record.

[2]  W. Kalender,et al.  Evaluation of a prototype dual-energy computed tomographic apparatus. II. Determination of vertebral bone mineral content. , 1986, Medical physics.

[3]  P. Paré,et al.  Quantitative assessment of airway remodeling using high-resolution CT. , 2002, Chest.

[4]  W. Kalender,et al.  Evaluation of a prototype dual-energy computed tomographic apparatus. I. Phantom studies. , 1986, Medical physics.

[5]  A. Macovski,et al.  Energy-selective reconstructions in X-ray computerised tomography , 1976, Physics in medicine and biology.

[6]  N L Müller,et al.  Chronic obstructive pulmonary disease • 4: Imaging the lungs in patients with chronic obstructive pulmonary disease , 2002, Thorax.

[7]  A. Fenster,et al.  Experimental dual xenon detectors for quantitative CT and spectral artifact correction. , 1980, Medical physics.

[8]  R M Slone,et al.  Repeatability of quantitative CT indexes of emphysema in patients evaluated for lung volume reduction surgery. , 2001, Radiology.

[9]  B. R. Pullan,et al.  X-ray energies for effective atomic number determination , 2004, Neuroradiology.

[10]  A. Macovski,et al.  Initial results with prereconstruction dual-energy computed tomography (PREDECT). , 1981, Radiology.

[11]  L. Feldkamp,et al.  Practical cone-beam algorithm , 1984 .

[12]  H K Genant,et al.  Measurement of bone mineral density at the spine and proximal femur by volumetric quantitative computed tomography and dual-energy X-ray absorptiometry in elderly women with and without vertebral fractures. , 2002, Bone.

[13]  R. Brooks.  A Quantitative Theory of the Hounsfield Unit and Its Application to Dual Energy Scanning , 1977, Journal of computer assisted tomography.

[14]  E. Kazerooni,et al.  Dual kV CT to Detect Calcification in Solitary Pulmonary Nodule , 1995, Journal of computer assisted tomography.

[15]  T. Lang,et al.  Quantitative computed tomography. , 2002, Seminars in musculoskeletal radiology.