MULTISLICE FIRST-PASS MYOCARDIAL PERFUSION IMAGING ON A CONVENTIONAL CLINICAL SCANNER

A technique is demonstrated for the acquisition and processing of multislice, first-pass contrast-enhanced perfusion images in the myocardium. The acquisition is a modification of ''keyhole'' imaging in which time series images are acquired by sampling a limited segment of k-space, corresponding to the low spatial frequencies. In the modification demonstrated here, keyhole samples are divided into two groups that are sampled on alternate cardiac cycles. The alternate ''missing'' k-space portions are synthesized by Fourier interpolation. Visualization of contrast agent accumulation by image subtraction is demonstrated. A motion artifact reduction process using time domain Fourier filtering is used to reduce artifacts from respiration. Studies were performed on 46 patients at 1.5 T using gadoteridol (0.05-0.1 mmol/kg) injected into the right antecubital vein in conjunction with radionuclide imaging. Fully concordant studies were noted in 27 of these patients. Remaining studies were either partially or completely discordant for reasons relating to the differing natures of radionuclide versus MR contrast agent characteristics.