Objective To study the capability in detection and qualitative analysis of carotid atherosclerotic plaque with 3.0T MR scanner.Methods Bilateral carotid arteriae in thirty-two patients with arterosclerosis which detected by Doppler ultrasound were examined with a 3.0T MR scanner.The pulse sequences included 3D time of flight,FLASH-3D,TSE-DIR T_1WI,TSE-DIR PDWI-FS,DIR TSE-T_2WI-FS and TSE-T_2WI.According to AHA modified criteria of atherosclerosis typing,the signal characteristics of plaques were analysed.Results Carotid plaques were homogeneous signal intensity on all sequences in 30/49,heterogeneous signal intensity on at least one sequence in 15/49,among them,7 with lipid core,3/49 plaques contained calcification ,2/49 appeared as thrombosis and resulting in vessel occulusion,28/49 plaques presented the character of thick fibrous cap,13/49 plaques showed character of thin fibrous cap,the surfaces of 5/49 plaques were rough.Conclusion High resolution multiple sequences imaging with 3.0T MR scanner can be used for detection and qualitative analysis of the carotid atherosclerotic plaque in a certain degree.

Objective To evaluate the repeatability and accuracy of semi-automated software OsiriX in the assessment of cartilage volume in normal knees on 3.0T MR. Methods Thirty right knees of healthy subjects were scanned twice with 3.0T MR using 3D-FLASH sequence with selective water excitation. Cartilage volume of the patellar compartment was determined with a validated open-source software OsiriX and manual segmentation separately by 3 observers using MRI data sets. After calculating the cartilage volumes, the segmentation processing times, the repeatability and volume results were compared between two segmentations. Results ①Compared with the manual segmentation, a time saving of at least 50% for cartilage volume measurement was achieved with OsiriX software segmentation. ②The interobserver repeatability error was 4.88% and 9.82% with OsiriX software segmentation and manual segmentation, respectively;the intraobserver repeatability error of high experienced observer was 0.77% and 1.29%, the interindividual repeatability range were 0.14%-1.11% and 0.52%-1.61%, respectively. The repeatability error of OsiriX software segmentaion was proved to be significantly smaller than manual segmentation (P＜0.05). ③System difference between results obtained with OsiriX software measurement and manual measurement was (-3.80±3.93)% and absolute pairwise difference was (4.68±2.70)%. There was no statistical difference between the volume results measured using two techniques (t=0.92, P=0.36). Conclusion Compared to manual segmentation, cartilage volume measurement with OsiriX semi-automated segmentation is faster and has higher inter- and intraobserver repeatability with relatively fixed standard. This technique may therefore be used for clinical and multi-center trials of large sample.

Objective To investigate the accuracy and reproducibility of multi echo data imagine combination (MEDIC) sequence with water excitation at 3. 0 T in swine knee cartilage. Methods Sagittal MEDIC sequences (0.6 mm slice thickness, isotropic) were acquired twice at 3. 0 T MRI in 30 swine knees. The knee cartilage was then removed and the volume was directly measured with water substitution method. The cartilage volume was also determined with a validated open source image software OsiriX by two observers ( A and B). The cartilage volumes obtained by two methods were compared. The reproducibility of MEDIC for quantitative measurement was accessed by the root-mean-square (RMS) of variation coefficient. Interobserver and intraobserver precision errors were compared using a paired students t-test. The accuracy of MEDIC for quantitative measurement was determined by the random pairwise differences, systematic pairwise differences and the Pearson correlation coefficients. Time of semiautomatic and manual segmentation were recorded. Results Time was saved about 75% by using semiautomatic segmentation methods [(4.0 ±1.5) min] versus manual segmentation [(16.0 ±0.9) min]. Interobserver precision errors (RMS CV%for paired analysis) between A and B for cartilage volume measurement were (2. 66 ±0. 82) ml and(2. 61 ±0.81) ml, t=0.24, P=0. 81 (patella); (2.40 ±0.69) ml and(2.49 ±0. 85) ml, t= -0.45,P =0. 65 (medial femoral condyle) ;(2. 28 ±0.74) ml and(2.41 ±0. 78) ml, t = -0. 66, P = 0. 51 (lateral femoral condyle);(3.43±1.28) ml and(3. 51 ±1. 08) ml, t= -0.26, P=0.79 (femora trochlea) with sagittal MEDIC. Intraobserver precision errors ( RMS CV% for paired analysis) of observer A for the first and second cartilage volume measurement were(2. 64 ±0. 62) ml and(2. 67 ±0. 60) ml, t = -0.19, P =0. 85(patella); (2.43 ±0.60) ml and(2. 39 ±0.59) ml, t =0.26, P = 0. 80 (medial femoral condyle);(2. 26 ±0. 56) ml and (2. 30 ±0. 57) ml, t = - 0.27, P = 0. 78 (lateral femoral condyle); (3.40 ±1.20) ml and(3.47 ±1. 11) ml, t = -0.23, P = 0. 82 (femora trochlea) with sagittal MEDIC. The cartilage volume of direct measurement were (2.73 ±0.97 ) ml ( patella ) , (2. 28 ±0. 66 ) ml ( medial femoral condyle) ,(2. 18 ±0. 55) ml (lateral femoral condyle) and (3. 39 ±1.31) ml (femora trochlea).Correlation coefficients between MEDIC and direct measurement for cartilage volume measurement were high [r = 0.95, t = 16. 10, P<0.05 ( patella); r=0.92, t = 12.42, P<0.05 (medial femoral condyle); r =0.94, t = 14.58, P < 0.05 (lateral femoral condyle) and r = 0.98, t = 26.06, P < 0. 05 (femora trochlea) ]. Conclusion Using image software OsiriX, sagittal MEDIC sequence permits accurate and precise measurement of cartilage volume at reasonable acquisition and segmentation time at 3.0 T MRI in swine knee.

Objective To observe the effects of cistanchis glycosides on scopolamine -induced impariment of learning and memory and on sodium nitrite -induced impariment of learning and memo ry consolidation in mice.Methods Step down test was performed to reflect th e learning and memory of mice.Cistan chis glycosides were administered c onsecutive-ly for 30days.The mice were trained o n the 29th day and measurements were c arried out on the 30th day .Latent period and number of errors within 5min were noted.Scopolamine was given by intr aperitoneal injection 15min before train-ing,and sodium nitrite was administered subcutaneously right after trainin g.Results(1)Compared with model mice in-duced by scopolamine,cistanchis glycosides 200and 400mg /kg together with piracetam 600mg /k g considerably in-creased latent period and decreased error times.Cistanchis glycosides100mg /kg also increased latent time but decreased error times to some extent.(2)Compared with model mice induced by s odium nitrite,cistanchis glycosides 200and 400mg /kg increased latent time significantly but had no significant effect on the error times.Cistanchis glycosides 100mg /kg decreased latent time and error time s to some extent.Conclusion Cistanchis glycosides could obviou sly improve scopo-lamine -induced impariment of learn ing and memory and on sodium nitrite -induced impariment of learning and memory in mice.