La Radiologia medica
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La Radiologia medica · Sep 1996
Comparative Study Clinical Trial[T2-dependent sequences in the study of hepatic focal lesions: comparison of the conventional spin echo sequence and the 0.5 T fast spin echo].
T2-weighted spin echo MR images are widely used in the detection and characterization of focal liver lesions. The main pitfall of this technique is its relatively long acquisition time. Fast spin echo sequences can provide the same contrast as conventional T2-weighted SE images in a shorter scanning time. ⋯ In the qualitative analysis, CSE sequences were superior to FSE for overall image quality in 50% of cases, for lesion conspicuity in 41.5% of cases and for internal features and the absence of artifacts in 46% of cases, FSE sequences had a higher detection rate in 17% of cases, even though both types of sequences underestimated the number of lesions in 29% of cases, as compared with the gold standard. To conclude, FSE sequences were inferior to CSE for image quality, lesion conspicuity, internal features and the absence of artifacts. FSE sequences were superior in the detection and characterization of fluid and nearly fluid lesions.
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La Radiologia medica · Sep 1996
Comparative Study Clinical Trial Controlled Clinical Trial[Fast spin echo imaging of vertebral metastasis: comparison of fat suppression techniques (FSE-CHESS, STIR-FSE)].
To investigate the capabilities of fast spin echo (FSE) sequences in diagnosing spinal metastases and to compare two fat-suppression techniques: CHESS (chemical shift selective saturation) and STIR (short T1 inversion recovery). Fat suppression is recommended with FSE sequences because on them, different from conventional spin echo (SE) sequences, fat has high signal intensity in both T1 and T2 weighting, masking such high-signal bone lesions as metastases. ⋯ Both STIR-FSE and FSE-CHESS sequences are rapid and useful techniques to obtain fat saturation in FSE images. CHESS saturation is selective on fat signal, while STIR suppresses the signal of all the substances with the same short T1 as fat.
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La Radiologia medica · Sep 1996
Comparative Study Clinical Trial[Magnetic resonance assessment of knee joint hyaline cartilage according to age, sex, and body weight].
To study the MR appearance of knee joint hyaline cartilage, 120 subjects were examined with MRI of the knee. Axial SE proton-density (PD) and T2, GE T1 and GE-MTC sequences were used, as well as coronal SE T1 and sagittal SE PD and T2 sequences. At the patellar and femorotibial cartilages the following variables were investigated: thickness, surface, signal intensity and visibility. ⋯ No statistically significant correlation was found between cartilage thickness, surface, signal intensity and visibility and age, sex, and body weight. The GE sequence was the best tool to study cartilage thickness and signal intensity, while the SE T2 sequence was the most accurate one to depict the articular surface and, together with the PD SE sequence, to visualize the trilaminar structure. Our study suggests that articular cartilage surface, thickness, and signal intensity can be studied accurately with SE PD and T2 sequences, combined with a GE T1 sequence.