La Radiologia medica
-
La Radiologia medica · Jun 1997
[Biomechanics and semiology of transient lateral patellar dislocation: reliability of magnetic resonance diagnosis].
Transient patellar dislocation is a rare finding. It is usually due to direct trauma in mediolateral direction or to indirect trauma related to violent quadriceps muscle contraction. The clinical diagnosis of transient forms is usually rather difficult because the associated signs (hemarthros and pain at the joint and/or at the vastus medialis insertion) are not specific. ⋯ Finally, other joint components, such as the posterior horn of the medial meniscus or the anterior cruciate ligament were involved in 6/13 cases. Arthroscopy was performed in 6 patients with associated injuries and confirmed all MR findings (100% agreement). To conclude, in our experience MRI was a very reliable tool to study the injuries due to transient patellar dislocation because it showed specific changes and possible associated traumas, which helps choose the most suitable treatment.
-
La Radiologia medica · May 1997
Comparative Study Clinical Trial[Comparison of magnetic resonance Spin-echo sequences and fat-suppressed sequences in bone diseases].
Thirty-two patients affected with skeletal conditions were examined with MRI using Short TI Inversion Recovery sequence and Spectral Presaturation with Inversion Recovery (SPIR) sequence as well as Spin-Echo (SE) T1-weighted sequence and Fast Spin-Echo (FSE) T2-weighted sequence to compare their value in the assessment of skeletal lesions. SPIR sequence was performed after intravenous injection of Gd-DTPA. The lesions included primary bone tumors (10 cases: 1 osteosarcoma, 1 periosteal sarcoma, 1 Ewing's sarcoma, 1 chondrosarcoma, 2 non-ossifying fibromas, 1 chondroma, 1 chondromyxoid fibroma, 1 desmoplastic fibroma and 1 bone cyst), metastases (7 cases: 3 prostate, 3 breast, 1 lung-squamous cell carcinoma), infections (12 cases: 9 osteomyelitis, 3 spondylodiscitis), sacroiliitis (1 case) and posttraumatic bone bruise (2 cases of bone marrow edema). ⋯ Quantitative evaluation showed statistically significant higher values of percent contrast (%C) and contrast-to-noise ratio (C/N) for STIR sequence compared with SPIR sequence (%C p < .004; C/N p < .040). This study suggests that STIR sequence and SE T1-weighted sequence provide high sensitivity in lesion detection and good anatomical definition. The use of a fat-suppressed sequence with Gd-DTPA can be useful for lesion characterization.
-
La Radiologia medica · May 1997
Comparative Study[Magnetic resonance of the brain: comparative assessment of conventional sequences versus fast sequences].
The conventional Spin-Echo sequences have been the most used acquisition techniques on Magnetic Resonance Imaging (MRI) of the brain, since the beginning of 1990s. Recently, however, technological developments proposed such new fast acquisition techniques, with a dramatic reduction in acquisition time as Gradient Echo, Turbo Spin Echo, Gradient Spin Echo ed Echo Planar sequences. We investigated the comparative adequacy of the new fast sequences, in brain MR studies versus conventional sequences, on medium field strength MR equipment (.5 T). ⋯ In conclusion, the present study suggests that fast acquisition techniques can improve the conventional protocol of sequences, in the anatomical representation of the normal brain even with medium field strength equipment only on T2 and T1-IR weighted images. On T1-weighted imaging conventional SE acquisition technique is still the best choice. The time saving obtained with fast sequences can therefore be used for an overall improvement in the quality of images, and to apply accessory acquisition plans on routine exams.
-
La Radiologia medica · Apr 1997
Comparative Study Clinical Trial Controlled Clinical Trial[Quantitative assessment of pulmonary emphysema with computerized tomography. Comparison of the visual score and high resolution computerized tomography, expiratory density mask with spiral computerized tomography and respiratory function tests].
CT is the most accurate method to detect pulmonary emphysema in vivo. We compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. ⋯ We believe the true residual volume should lie somewhere in between the CT value and the function results with the helium dilution technique and conclude that the extent of pulmonary emphysema can be confidently assessed with CT methods. Finally, the simple visual score may be as reliable as such highly sophisticated new methods as the spiral expiratory density mask. Expiratory studies offer new insights into different normal and abnormal features of COPD and respiratory impairment.