NMR relaxation time studies of large bowel neoplasms.
The purpose of the study was to determine if measurements of the NMR relaxation times could be useful in distinguishing healthy from neoplasmatic tissue in in vitro study of the slices from the large bowel obtained during surgery before histological examination. Tissue samples taken from the center of the tumor and from the distal part of the excised large bowel segment were stored at 4 degrees C in closed tubes not longer than 24 hours. The measurements were performed at 37 degrees C using a pulse spectrometer operating at 27 MHz. After NMR investigation all the tissue samples were preserved and carefully examined by conventional histopathological techniques. Both for the T1 and the T2 the mean values of the relaxation time for the respective neoplasmatically changed group and normal, non-changed group, were statistically different. However, the differences in measured relaxation times are too small to use the NMR method alone for diagnosis. The NMR method can be useful only for an initial selection of tissue samples with possible cancer changes but histopathological examination is required to verify that cancer is present in the tissue.