ABSTRACT
Objective To evaluate the accuracy of MR in the diagnosis of tumor thrombus in renal cell carcinoma.Methods 22patients with renal cell carcinoma proved pathologically were recruited in this study.All the patients underwent MR examination beforesurgery.The results of the MR were correlated with that of the operation.Results 8 renal veins could be found tumor thrombus during the surgery,and the other 14 renal veins and 22 inferior vena cava were absent of tumor thrombus.MR could found all of the 8 tumor thrombithat detected by the surgeons.In the other 14 cases,13 of them could be excluded of tumor thrombus by MR.Only in 1 patient,the MRresult was equivocal.CT was performed in 9 patients,the diagnosis was accurate in 7 cases,and was inaccurate in 2.Ultrasound wasperformed in 16 patients,the diagnosis was accurate in 13 cases,and was inaccurate in 3.Digital subtraction angiography was performed in 4 cases,the diagnosis was correct in all of them.Conclusion MR is perfect in the diagnosis of tumor thrombus in renal cell carcinoma oncondition that the renal vein is clearly defined by MR.It can be considered as the method of choice in the evaluation of tumor thrombus inrenal cell carcinoma.
ABSTRACT
Objective To compare pediatric patients with periventricular leukomalacia (PVL) with normal children by using diffusion tensor MR imaging. Methods Diffusion tensor images were obtained in 15 pediatric patients with PVL and 15 age-matched normal children. Regions of interest were drawn to measure the fractional anisotropy (FA) in bilateral posterior limb of internal capsule, bilateral optic radiation, genu of corpus callosum, and splenium of corpus callosum. The values of PVL patients and normal children were compared using non-dependent samples T-test. Results The FA values of regions of interest prescribed were significantly lower in PVL patients than in normal children(P
ABSTRACT
Objective To evaluate the diagnostic accuracy of dual-energy subtraction chest digital radiography(DR) for detecting coronary artery calcification as compared with multi-detector row CT(MDCT).Methods 35 patients underwent dual-energy subtraction chest DR and ECG-gated MDCT for detection of coronary artery calcifications.The radiation dose of both DR and CT were noted respectively.Two senior and two junior radiologists reviewed the radiogram and assessed the calcifications in LAD,LCX and RCA totaling 105 vessels.ROC curve plotting were used for evaluation with CAC calculated from MDCT as the gold standard.Paired t test was calculated to compare the different radiation dose between DR and CT.Results 27.6% vessels(29/105) showed calcification on DR.The positive incidence in LAD was 48.5%(17/35),LCX 22.8%(8/35),and RCA 11.4%(4/35).The ROC area was 0.866,0.854,0.725,0.642 respectively,with a CAC score of more than 300.The average radiation dose was 0.469?0.22 mGy for DR,and 12.29?1.40 mGy for MDCT,showing significant differences.Conclusion Chest DR with dual energy subtraction can be used for screening of coronary artery calcification with relatively higher sensitivity for LAD.