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The quality of a Teboroxime single-photon emission computed tomography (SPECT) study ran be degraded by Teboroxime's rapid myocardial washout and high liver uptake. Described is the use of fast-fanning acquisition and nonlinear regression with distance penalty (NLRDP) to compensate for the two effects. Tl-201/conventional single-rotation Sestamibi (MIBI) and Tl-201/dynamic fast-fanning Teboroxime (TEBO) rest/stress acquisitions were conducted on 18 subjects. TEBO reconstructions were processed by NLRDP using group-averaged kinetics to separate images into liver, myocardium, and background. Reprojections of these compartments were registered with the measured projections. This made possible the extraction of patient-specific kinetics. NLRDP identified defects (abnormal myocardium with different kinetics from normal tissue) by differences in the kinetics of the defect pixels. Enhanced-TEBO (E-TEBO) images were produced by using the kinetic curves to calculate the Teboroxime concentration in each pixel at the time of expected peak myocardial uptake and by omitting the liver compartment. Stress and reversibility total severity scores and total impaired and reversible myocardial mass were computed for the MIBI, TEBO, and E-TEBO images using the Emory Cardiac Toolbox. Regression and correlation analyses of these quantitative indices indicate that Teboroxime SPECT can produce results similar to those of Sestamibi SPECT if E-TEBO images are generated. Index Terms--Dynamic single-photon emission computed tomography, fast-fanning acquisition, nonlinear regression with distance penalty, technetium-99m Teboroxime.

Patients with multivessel coronary heart disease who are treated with percutaneous transluminal coronary angioplasty (PTCA) seem to have similar rates of subsequent heart attacks and death as those treated with coronary artery bypass grafting (CABG). However, significantly more PTCA patients require further surgery. Researchers studied 392 patients with coronary artery disease in more than one artery. PTCA was performed on 198 patients while the other 194 patients had CABG. Within three years after the procedure, approximately 6% of CABG patients and 7% of CABG patients had died. Approximately 20% of PTCA patients and 15% of CABG patients had a heart attack during follow-up. Decreased blood supply to areas of the heart was noted in approximately 10% of PTCA patients and 6% of CABG patients. The type of treatment did impact the rates of additional vascular surgery. Fifty-four percent of PTCA patients and 13% of CABG patients had additional heart-vessel surgery during the follow-up period.

Prompted by clinical concerns for false-negative tests, we implemented a clinical intervention consisting of a training session and an image-based verification procedure to document homogeneous radioactivity distribution in the radiolabeled meal (egg substitute per the guideline). Methods: A technologist training session emphasized the importance of thorough mixing of 99mTc-sulfur colloid in the egg meal. For 6 mo after training, an image of the prepared mixed egg was acquired before patient ingestion. Consecutive gastric-emptying studies performed 6 mo before and after training were reviewed by 2 experienced physicians. Results: There were 7 abnormal and 44 normal studies before and 15 abnormal and 29 normal studies after training (P < 0.05). Subjective evaluations of images for meal-mixing quality by 2 readers correlated with each other and with an objective measure of expected gastric-emptying physiology (correlation coefficients, 0.54 and 0.38, respectively). Conclusion: The described clinical intervention improved the accuracy of our gastric-emptying studies by decreasing false-negative studies. [ABSTRACT FROM AUTHOR]

The quality of a Teboroxime single-photon emission computed tomography (SPECT) study can be degraded by Teboroxime's rapid myocardial washout and high liver uptake. Described is the use of fast-fanning acquisition and nonlinear regression with distance penalty (NLRDP) to compensate for the two effects. Tl-201/conventional single-rotation Sestamibi (MIBI) and Tl-201/dynamic fast-fanning Teboroxime (TEBO) rest/stress acquisitions were conducted on 18 subjects. TEBO reconstructions were processed by NLRDP using group-averaged kinetics to separate images into liver, myocardium, and background. Reprojections of these compartments were registered with the measured projections. This made possible the extraction of patient-specific kinetics. NLRDP identified defects (abnormal myocardium with different kinetics from normal tissue) by differences in the kinetics of the defect pixels. Enhanced-TEBO (E-TEBO) images were produced by using the kinetic curves to calculate the Teboroxime concentration in each pixel at the time of expected peak myocardial uptake and by omitting the liver compartment. Stress and reversibility total severity scores and total impaired and reversible myocardial mass were computed for the MIBI, TEBO, and E-TEBO images using the Emory Cardiac Toolbox. Regression and correlation analyses of these quantitative indices indicate that Teboroxime SPECT can produce results similar to those of Sestamibi SPECT if E-TEBO images are generated. [ABSTRACT FROM AUTHOR]