The Total Entropy for Evaluating31P-Magnetic Resonance Spectra of the Liver in Healthy Volunteers and Patients with Metastases

摘要

RATIONALE AND OBJECTIVESThe authors describe the clinical status of liver tissue with only a single numerical quantity (total entropy) derived from spectroscopic data of31P-magnetic resonance (MR) spectra.METHODSTwenty-four patients with liver metastases and 20 volunteers were investigated with image-guided volume selective31P-MR spectroscopy on a 1.5-T whole body scanner. From each in vivo31P-MR spectrum, the ratios of phosphomonoester(PME)/beta;-adenosine triphosphate (ATP), inorganic phosphate (Pi)/beta;-ATP and phosphodiester (PDE)/beta;-ATP and the total entropy (H*) were calculated. Mean values and standard deviations were determined and significance of the differences were tested with Student'sttest.RESULTSFor patients, the H* equals; 4.7 plusmn; 4.3, PME/beta;-ATPequals; 0.72 plusmn; 0.28, Pi/beta;-ATP equals; 1.00 plusmn; 0.39, PDE/beta;-ATP equals; 1.68plusmn; 0.59. For the volunteers, H* equals; 7.6 plusmn; 2.5, PME/beta;-ATP equals; 0.39 plusmn; 0.15, Pi/beta;-ATP equals; 0.90 plusmn; 0.19, PDE/beta;-ATPequals; 1.25plusmn; 0.28. The total entropy of patients' spectra showed significantly lower values compared with those of volunteers. PME/beta;-ATP and PDE/beta;-ATP of the patients increased and differed significantly from volunteer data.CONCLUSIONSIt was demonstrated that the results of in vivo31P-MR spectroscopy may be described with a single criterion by means of the total entropy.