| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
Correspondence: For correspondence or reprints contact: Jerold W. Wallis, M.D., Mallinckrodt Institute of Radiology, 510 South Kingshighway, St. Louis, MO 63110.
ABSTRACT
The accuracy of SPECT cardiac perfusion imaging is impaired by artifacts induced by nonuniform gamma-ray attenuation. This study proposes a method to estimate attenuation in the chest of patients without the additional hardware and expense of transmission imaging. Methods: After the standard 201TI or 99mTc-sestamibi delayed images were obtained, 99mTc macroaggregated albumin (MAA) was injected and dual-energy SPECT acquisition was performed with windows centered at 140 keV and 94 keV. Lung contours were obtained by thresholding the on-peak (140 keV) reconstructions. Outer body contours were defined from images produced by reconstruction of the lower energy scatter window obtained simultaneously at the time of the lung (MAA) imaging. Following assignment of standard attenuation values to the lung and nonlung (soft tissue) regions attenuation correction was achieved by means of a modified iterative Chang algorithm. The results were quantitatively evaluated by imaging of a cardiac phantom filled with uniform activity placed in a chest phantom. Sensitivity to the choice of lung and soft tissue attenuation values, the choice of the threshold used for lung segmentation, and errors in registration of the attenuation map were assessed. Results: Application of this technique in a chest phantom and in patients imaged with both 201TI and 99mTc-sestamibi resulted in improvement in artifactually decreased inferior wall activity without adversely affecting the other walls. The results were relatively insensitive to choice of values for lung and soft-tissue attenuation, lung thresholding, and small (
1.3 cm) registration errors. Conclusion: This simple method corrects for nonuniform attenuation in males; studies are underway to adapt the method to determine breast contour in females and to determine the value of the method in clinical practice.
Key Words: SPECT • attenuation correction • cardiac perfusion imaging • coronary artery disease
This article has been cited by other articles:
|
|
 |
|
  T. A. Morris, J. J. Marsh, P. G. Chiles, R. G. Konopka, C. A. Pedersen, P. F. Schmidt, and M. Gerometta Single Photon Emission Computed Tomography of Pulmonary Emboli and Venous Thrombi Using Anti-D-Dimer Am. J. Respir. Crit. Care Med., May 1, 2004; 169(9): 987 - 993. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Zaidi and B. Hasegawa Determination of the Attenuation Map in Emission Tomography J. Nucl. Med., February 1, 2003; 44(2): 291 - 315. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. J. Gibbons, D. O. Hodge, D. S. Berman, O. O. Akinboboye, J. Heo, R. Hachamovitch, K. R. Bailey, and A. E. Iskandrian Long-Term Outcome of Patients With Intermediate-Risk Exercise Electrocardiograms Who Do Not Have Myocardial Perfusion Defects on Radionuclide Imaging Circulation, November 23, 1999; 100(21): 2140 - 2145. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. G. Hundley, C. A. Hamilton, M. S. Thomas, D. M. Herrington, T. B. Salido, D. W. Kitzman, W. C. Little, and K. M. Link Utility of Fast Cine Magnetic Resonance Imaging and Display for the Detection of Myocardial Ischemia in Patients Not Well Suited for Second Harmonic Stress Echocardiography Circulation, October 19, 1999; 100(16): 1697 - 1702. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| JOURNAL OF NUCLEAR MEDICINE TECHNOLOGY | THE JOURNAL OF NUCLEAR MEDICINE |
