[en] Objective: To assess the diagnostic value of MSCT and MR perfusion in the differentiation of benign and malignant soft tissue tumors. Methods: Twenty-six patients with soft tissue tumors were studied in MSCT perfusion and 29 patients in MR perfusion. The differences of perfusion parameters of benign and malignant tumors were analyzed. Results: The average value of MSCT BF was (24.49 ± 14.49) ml·100 mg^-1 · min^-1 for malignant group, and (1.98 ± 1.19) ml·100 mg^-1 · min^-1 for benign group. PS was (14.64 ± 1.89) ml·100 mg^-1·min^-1 for malignant group, and (2.40 ± 0.38) ml·100 mg^-1·min^-1 for benign group. The mean BF and PS in benign and malignant tumors had significant difference in MSCT perfusion. The sensitivity , specificity, accuracy, positive predictive value, and negative predictive value of MSCT in estimating the potential malignancy of the tumors were 90.9%(10/11), 86.7%(13/15), 88.5%(23/26), 83.3%(10/12), and 92.9%(13/14), respectively. The average value of MR BF was (0.11 ± 0.02) ml·100 mg^-1·min^-1 for malignant group, and (0.07 ± 0.01) ml·100 mg^-1·min^-1 for benign group. The mean BF in benign and malignant tumors has significant difference in MR perfusion. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR in estimating the potential malignancy of the tumors were 91.7%(11/12), 88.2%(15/17), 89.7%(26/29), 84.6%(11/13), and 93.8%(15/16), respectively. Conclusion: MSCT and MR perfusion are very helpful in the differentiation of benign soft tissue tumors from malignant ones. (author)

[en] Objective: To investigate the feasibility of MR angiography of the dorsalis pedis artery (DPA), the first dorsal metatarsal artery (FDMA) and the branches at the first toe web by three-dimensional time-resolved imaging of contrast kinetics (TRICKS) sequence. Methods: Forty three patients with suspected or known soft tissue diseases of the ankle and foot were examined retrospectively by MR TRICKS sequence. Two experienced radiologists independently evaluated the visualization performance of DPA, FDMA and its branches with maximum intensity projection. Kappa analysis was performed for the image evaluation of the two radiologists. Consensus scores were obtained if the two radiologists had different scores. Clinical classification of FDMA was carried out for patients with scores equal to, or more than 2 points after imaging evaluation. FDMA was categorized according to its location (superficial, intramuscular, infra-muscular, absent), diameter (large, medium and small) and branching pattern at the toe web (ramifying type, main trunk type and fine small branch). Results: The scoring results of the two radiologists indicated a high agreement (Kappa value =0.895, P<0.05). TRICKS images can clearly show the arterial filling of DPA, FDMA and its branches. The final consensus scores were as follows: 8 patients had 4 grade and 22 patients 3 grade, 8 patients 2 grade and 5 patients 1 grade. Clinical classification of FDMA for 38 patients (arterial scales ≥2 point): (1) Location: superficial (8 patients), intramuscular (23 patients), intramuscular (7 patients); (2) Diameter at the midpoint of FDMA: large (2 patients), medium (25 patients), and small (11 patients); (3) Branching pattern at the toe web: ramifying type (11 patients), main trunk type (5 patients), fine branch (14 patients). Conclusion: MR TRICKS sequences are valuable in the evaluation of the DPA and FDMA and its branches, which can provide useful anatomical information for classification of FDMA. (authors)

[en] Objective: To study the application of multislice spiral CT (MSCT) in the diagnosis of pulmonary embolism (PE) with emphasis on subsegmental PE. Methods: Thirty-four cases with both sexes of PE were analyzed. The average age was 56 years, from 33 to 77 years. The history included deep venous thrombosis in 16 cases, post-operation in 11 cases, lung cancer in one case, and with unknown reason in 6 cases. 34 patients underwent MSCT (Lightspeed plus, GE) with acquisition of 4 slices for one scan, the slice thickness was 2.5 mm, with all length 150-170 mm and scan time 0.6-0.8 s. Nonionic contrast media (100 ml, 300 mg I/ml) was administered, the flow rate was 3.5 ml/s, the delay time was 12-15 s, and the scan time was 17-20 s. The reconstruction of MSCTA was from MIP, SSD, VR and endoscopy. Results: In 34 patients studied by MSCT and MSCTA, pulmonary arteries were demonstrated in 1824 branches, and PE was detected in 507 branches (27.8%). For segmental pulmonary arteries, 36.2% showed PE, and for subsegmental pulmonary arteries, 13.5% showed PE. The indirect signs of the plain MSCT included: reduced pulmonary vascular markings (19 cases), pulmonary hypertension (2 cases), pleural effusion (16 cases), subpleural infarction (41 foci). On post-contrast MSCTA, the direct sign was the filling defect in the pulmonary arteries branches at various degrees, and four forms of the filling defect included central filling defect in 57 branches, eccentric filling defect in 160 branches, embolism attached to the wall of host artery in 131 branches, total occlusion of the pulmonary arteries in 159 branches. Conclusion: MSCT is a fast, effective, and non-invasive diagnostic method for PE. It may replace the pulmonary angiography (DSA) and it is as good as EBCT. It will be the gold standard for diagnosis of pulmonary embolism

[en] Objective: To evaluate the deep brain venous blood oxygen content changes in patients with multiple sclerosis(MS) using susceptibility weighted imaging (SWI), and to explore the ability of SWI in reflecting the clinical condition. Methods: Forty-four MS patients were prospectively enrolled in the study. All the clinical-proved patients meeting the McDonald standards (2005 revised) underwent conventional MRI, SWI, and 12 cases of them underwent MRI review from 12 to 16 months interval. all the patients' clinical condition were quantified according to the expanded disability status scale(EDSS). The score was 0.5-6.5. Sixty-five age- and gender- matched healthy volunteers underwent conventional MRI and SWI. The blood oxygen content of the deep brain venous were estimated by the veins phase value, and differential phase values of blood vessels and surrounding tissues (Δφ) were processed with SPIN software. The blood vessels consist of bilateral BV, SMCV, ICV, STV and FMV, PMV, OMV. The difference of Δφ value in different veins between MS patients and the controls was compared using independent sample t-test, and the Δφ value comparison of MS patients in different time were performed by using paired t test; The correlation of value between MS and EDSS was analyzed using Spearman correlation. Results: The Δφ value of BV, SMCV, ICV, STV were 856.6 ± 246.4, 600.6 ± 155.2, 965.9 ± 205.4, 844.2 ± 149.7 in MS, and 767.6 ± 145.1, 536.2 ± 123.5, 892.8 ± 156.3, 783.1 ± 148.5 in controls, respectively. The Δφ value was higher in MS patients than the controls (t = 2.157, 2.303, 2.005, 2.103, P < 0.05). The twelve patients' Δφ values of BV, ICV, STV were 729.4 ± 275.1, 906.1 ± 219.2, 737.2 ± 159.1 in the first time, and 923.2 ± 211.6, 1017.3 ± 211.1, 919.3 ± 165.9 in the second time, and all the values increased in the review, of the interval of 12 to 16 months (t = -3.092, -6.420, -3.972, P < 0.05). The phase value of PMV and OMV had significant positive correlation with EDSS scores(r = 0.638, 0.642, P < 0.01). Conclusions: The state of hypoxia of the brain parenchyma appears in MS patients, and hypoxia may become worse with the extension of course. The extent of hypoxia can reflect the disability of the patients. (authors)