Objective To evaluate the magnetic resonance angiography(MRA) in senile lower extremity arterial disease and to compare the diagnostic value of two dimensional time of flight(2D TOF) with three dimensional contrast enhancement(3D CE) technique. Methods Seventy patients with a mean age of 75 years underwent MRA for suspected acute or chronic lower extremity arterial disease. MRA was performed with a 1 5 T MR scanner and Gd DTPA was used by manual injection in 3D CE MRA. Among 52 patients examined with 2D TOF MRA, 18 of them underwent an additional 3D CE MRA, 32 patients took Doppler ultrasound examination, and 4 patients received emergency operation. Results In all 70 patients, 52 showed atherosclerotic stenosis disease, 17 atherosclerotic occlusive disease (4 of them were verified by emergency operation) and one patient atherosclerosis with aneurysmal dilatation. A total of 997 vessel segments were shown on MRA images and 600 of them were abnormal including 486(81%) mild to moderate stenoses, 114(19%) severe stenoses and 451 curved arterial segments. In 32 patients who underwent Doppler ultrasound, the diagnosis and its grading based on MRA was well correlated with that from Doppler ultrasound (coincidence rate was 91% and 96% respectively). A total of 764 suprapopliteal and 125 infrapopliteal arteries were depicted by 2D TOF MRA (visibility was 99% and 40% respectively). In 18 patients who received additional 3D CE MRA, totally 306 arteries were depicted on MRA (visibility 100%). Doppler ultrasound showed 40 segments with arterial calcification and 32 atherosclerotic plaques. Conclusions MRA is quite useful in detecting lower extremity arterial disease because of its noninvasion and convenience. The results derived from MRA are well correlated with that of Doppler ultrasound and clinical outcome. 3D MRA is superior to 2D TOF MRA in image quality, accuracy and time efficiency and is best for emergency case. Pitfalls of MRA such as overestimation in the severity of the disease and the long scanning time of 2D TOF must be taken into consideration .

Objective To investigate the value of magnetic resonance (MR) diffusion weighted imaging(DWI) in the diagnosis of prostate cancer(PCa). Methods Fifty-seven patients with suspected prostate cancer underwent DWI and T_2-weighted imaging (T_2W). These images and apparent diffusion coefficient (ADC) maps results were compared with histopathologic findings. Receiver operating characteristic(ROC) analysis was used to compare the cancer detection performance of them. The results were rated on a scale of scores Ⅰ (benign) to Ⅴ (malignant) on the basis of ADC maps. Abnormal voxels were overlaid on the corresponding transverse TRUS images and used to perform voxel-guided biopsy. Results DWI had a sensitivity of 85%, specificity of 82%, positive predictive value of 80%, negative predictive value of 86% , and accuracy of 83%. T2WI had a sensitivity of 77%, specificity of 71%, positive predictive value of 69%, negative predictive value of 79%, and accuracy of 74%. The areas under the ROC curves for DWI and T_2WI were 0. 830 and 0. 742, respectively. The performance of DWI in PCa detection was significantly better than of T_2WI (P<0. 05). 6 of 30 patients with negative DWI results also had negative biopsy findings. PCa was detected in 17(85%) of 24 men findings with voxel score Ⅳ , with a sensitivity of 100%, specificity of 46%, positive predictive value of 71 %, negative predictive value of 100% , and accuracy of 77%. Conclusions The performance of DWI in PCa detection was better than of T_2 WI. ADC maps can be transferred to TRUS images and used to sample regions of cancer in men with rising PSA levels and negative findings at prior biopsy with good accuracy. DWI appears to be a robust and reliable method to examine the whole prostate within an acceptable scan time in clinical settings.

Objective To evaluate the accuracy of multi-detector-row CT (MDCT) in the diagnosis and preoperative evaluation of breast cancer. Methods From January 2004 to December 2007,the clinical data of 54 cases wih pathologically proved breast cancer undergoing preoperative MDCT scan (31 cases also underwent MRI scan) were retrospectively analyzed at our hospital. Surgical planning was based on MDCT assessment. The extent and location of tumor depicted by MDCT,MRI and pathology were compared. Results Breast carcinoma was diagnosed by MDCT in all the cases. In these 54 patients,MDCT achived an accuracy of 87% in evaluating the extent of tumor. Based on MDCT,39 cases underwent BCT surgery with a 8% margin positive rate. MDCT and MRI had no significant difference in accuracy of evaluation on the extent of tumor ( x2 = 0. 5, P ＞ 0. 05 ). Conclusions MDCT accurately assesses the extent and location of breast cancer, proving its value in preoperative evaluation of breast cancer.

Objective To evaluate the roles of proton magnetic resonance spectroscopy(1H-MRS) and the volume of the hippocampus(HCV) measured by MRI in the diagnosis and the differential diagnosis of mild cognitive impairment (MCI) and mild Alzheimer disease (AD).Methods HCV and 1H-MRS were performed in the bilateral hippocampus and the bilateral medial temporal lobes(MTLS) in 30 cases with MCI,30 cases mild with AD and 30 healthy persons in age and sex-matched with controls by using volume analysis software and stimulates echo acquisition mode(STEAM). The ratios of NAA/Cr,Cho/Cr,MI/Cr,NAA/MI and HCV were compared among these groups.The contributions of HCV and 1H-MRS in diagnosis of MCI and AD was compared.Correlation coefficients were calculated for Mini Mental State Examination (MMSE) scores and HCV or the ratios of NAA/Cr,Cho/Cr,MI/Cr and NAA/MI in the MCI group and the mild AD group.Results Patients with mild AD showed significant reduction of HCV and NAA/Cr and NAA/MI ratios in the bilateral HCVand MTLS,and significant MI/Cr increase in the bilateral MTLS relative to control subjects. Patients with MCI demonstrates significant reduction of NAA/Cr in the left MTL , significant reduction of the bilateral HCV and NAA/MI ratio and significant MI/Cr increase in the bilateral HCV and MTLS relative to control subjects. Patients with mild AD showed statistical differences of MI/Cr and NAA/MI ratios in the left MTL relative to patients with MCI . Patients with mild AD showed no significant differences of HCV and NAA/Cr relative to patients with MCI .The Cho/Cr ratios among three groups showed no significant differences. HCV yielded the volume with the sensitivity 50% and specificity 83.33% in the diagnosis of MCI . 1H-MRS yielded the ratios with 43.33% in sensitivity and 81.25% in specificity in the di- agnosis of MCI.The combination of HCV and 1H-MRS yielded the volume and ratios with sensitivity of 73.33% and specificity of 84.62% in the diagnosis of MCI. HCV yielded the volume with sensitivity of 73.33% and specificity of 88% in the diagnosis of mild AD.1H-MRS yielded the ratios with sensitivity of 70% and specificity of 87.5% in the diagnosis of mild AD.The combination of HCV and 1H-MRS yielded the volume and ratios with sensitivity of 83.33% and specificity of 86.21% in the diagnosis of mild AD. HCV yielded the volume with the sensitivity of 50% and specificity of 62.5% in the differential diagnosis of MCI and mild AD.1H-MRS yielded the ratios with sensitivity of 56.67% and specificity of 65.38% in the differential diagnosis of MCI and mild AD.The combination of HCV and 1H-MRS yielded the volume and ratios with sensitivity of 66.67% and specificity of 64.52% in the differential diagnosis of MCI and mild AD. Patients with mild AD and MCI showed significant correlation between MMSE and the bilateral HCV ,NAA/Cr ratio. Patients with mild AD showed significant correlation between MMSE and right NAA/MI ratio .Patients with mild AD and MCI showed significant correlation between HCV and NAA/Cr ratio. Conclusion The combination of HCV and 1H-MRS are the best choice in the diagnosis and the differential diagnosis of MCI and mild AD.

0.05).Results No side effect was recorded.100% of images were with excellent quality.Conclusion Patients with previous endovascular stent surgery can receive 1.5T high field MRI examination safely.Usually the examination can be performed in 4~8 weeks after the surgery,but in special case,earlier examination is also acceptable.

Objective To evaluate usefulness of high-resolution MRI in quantitative analysis of femoral micro-structure.Methods This study included 110 cases which were divided into 4 groups according to the results of DXA.High-resolution MRI of left hip joint wasperformed on a 1.5T super-conductive MR scanner.3 ROIs were selected on the largest oblique-coronal images of femur to gain thebinary images derived from software processing and 30 parameters were analyzed.Results The parameters to be of statistical significance were 77% and 67%,respectively.Full points of structural parameters with significant difference were 6,4~6 points were 60% and 2~3 points were 40%.Trabecula connective parameters such as trabecula area,mean framework length and mean trabecula perimeter had positive correlation with bone density,r=0.547～0.722,0.58～0.654 and 0.573～0.688,P

Objective To This article mainly takes the Shenzhen Baoan people's Hospital pre-hospital department as the observation object,analyses the spacial site data distribution of pre-hospital,to realize optimum allocation for pre-hospital resource.Methods By means of the intelligentized ambulance,the site data of the pre-hospital is obtainecd,so is the pre-hospital hot map.With the hot map,the special pre-hospital characteristics is researched.Results The three spatial data characteristics of pre-hospital medical are proposed,i.e.,non-uniform,relative stability,individual difference.Conclusions These three characteristics provide us with a new method and a new basis for decision making.In this paper,based on the pre-hospital characteristic,a modeling method of non-uniform relative stability model is proposed,and the optimized distribution of hospital site is discussed by applying planning mathematics.