Dynamic cardiac SPECT with Tc-99m Teboroxime: compensation for rapid myocardial washout and high liver uptake

Abstract

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 a fast-fanning acquisition protocol 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 the images into liver, myocardium, and background compartments. Re-projections of each compartment were registered with the measured projections, allowing the extraction of the 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 omitting the liver compartment. 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 similar results as Sestamibi SPECT if E-TEBO images are generated.