The usefulness of computer tomography and MR in the assessment of focal lesions in the liver

The aims of this study was to assess the sensitivity, specificity, and accuracy of computed tomography (CT) and magnetic resonance (MR) with the final diagnosis of focal liver lesions; to assess the significance of the sequences of MR examination in the evaluation of the focal liver lesions, and finally, to position both methods in diagnostic algorithm of focal liver lesions. The CT and MR were performed in 126 patients (71 female and 55 male), 25 to 80 years old, diagnosed, based on the US or clinical examination, with focal lesions in the liver. The CT examination was performed prior to contrast medium administration, and in the portal and parenchymatous phase, enhanced with contrast medium. The MR examination was performed with 0.5 T apparatus, SE/T1 sequence, prior and after administration of Gd-DTPA, SE or TSE/heavily and moderate T2, STIR/T2. The following were evaluated: number, size, location and kind of contrast enhancement, shape, degree of outline sharpness, density, and intensity of signals of revealed focal. In 60 patients 162 metastasis were found, in 41 patients - 87 haemangioma, in 13 patients - 23 foci of primary carcinoma, in 12 patients the presence of focal in the liver was denied. The differences in the sensitivity in detection of haemangioma and metastases were statistically significant (p<0.00001), with the superiority of MR. The differences between CT and MR in specificity were not statistically significant. In a view of comparable specificity of CT and MR examination in the assessment of focal liver lesions, both methods can be applied to differentiate focal lesions that were found in US examination. Taking into consideration, however, the higher sensitivity of MR in detecting small metastases, this is the method to be used in patients planned for radical surgical treatment of neoplastic lesions. (author)