Objective: To explore the changes and significance of local brain activity in different motor subtypes of Parkinson disease(PD) using resting-state functional MRI (rs-fMRI) based on regional homogeneity (ReHo) analysis. Methods: A total of 84 PD patients and age-and gender-matched 29 healthy controls undergoing rs-fMRI were included. PD patients were divided into two groups of tremor dominant(TD) (n=45) and postural instability gait difficulty(PIGD) (n=39) according to the Unified Parkinson′s Disease Rating Scale (UPDRS) scores. Data processing assistant for resting-state fMRI (DPARSF) and resting-state fMRI data analysis Toolkit (REST) V1.8 based on MATLAB were used to calculate the ReHo which measured brain activity in different motor subtypes of PD. Analysis of covariance and post-hoc t-tests were performed to detect the differences of local brain activity among the three groups.Correlation analyses were performed between ReHo values of the regions showing group differences and TD and PIGD scores respectively. Results: Compared to healthy controls, the TD group exhibited increased ReHo in the right superior and middle frontal gyrus, left cerebellum(13 to 21 voxels, P<0.05), while decreased ReHo in the left temporal lobule, left putamen, left paracentral lobule, and bilateral thalamus (12 to 91 voxels, P<0.05). The PIGD group showed increased ReHo in the right superior frontal gyrus, right middle frontal gyrus and anterior cingulate gyrus (ACC) (55 to 92 voxels, P<0.05), while decreased ReHo in the left putamen, left pallidum, left temporal lobule, right occipital lobule, bilateral thalamus, bilateral middle cingulate gyrus, bilateral supplementary motor area (SMA) (15 to 78 voxels, P<0.05). Compared with PIGD, the TD group showed increased ReHo in the left temporal lobule, left cerebellum, bilateral middle cingulate gyrus (19 to 51 voxels, P<0.05), whereas decreased ReHo in the left paracentral lobule, bilateral cuneus, right superior frontal gyrus, and right ACC (14 to 68 voxels, P<0.05). Additionally, ReHo in the left thalamus and left putamen negatively correlated with TD scores (r=-0.355 and -0.498, both P<0.05). ReHo in the left thalamus and right thalamus negatively correlated with PIGD scores (r=-0.478 and -0.397, both P<0.05). Conclusions The changes of brain activity in TD are located in the cerebello-thalamo-cortical (CTC) circuit and the striatal-thalamo-cortical (STC) loop while the changes in PIGD are largely located in the STC loop and visual network cortex. This specific pattern of intrinsic activity in TD and PIGD may provide insights into the neurophysiological mechanisms of PD with different motor subtypes.

Purpose To investigate the prognostic value of whole-body magnetic resonance imaging (WB-MRI) for patients with multiple myeloma (MM).Materials and Methods Sixty-two newly diagnosed patients with MM confirmed by pathology during January 2010 and December 2016 were enrolled in this study.The patients were divided into five groups according to the infiltrative patterns on MRI:normal pattern,micro-nodular pattern,macronodular pattern,mixed pattern and diffuse pattern,and their overall survival were compared.Results Of all the patients,micro-nodular infiltrative pattern was found in 20 patients,macro-nodular pattern in 13 patients,mixed pattern in 7 patients and diffuse pattern in 17 patients,while 5 patients were normal.During the follow-up for a median of 39 months (ranged 30.9-47.1 months),overall survival with the mixed MM infiltrative pattern (median 17 months,95％ CI 12.6-21.3 months) was statistically shorter than those with other patterns (median 43 months,95％ CI 33.7-52.3 months;P＜0.05).Additionally,the clinical DurieSalmon (DS) and International Staging System (ISS) were applied to evaluate the stage of MM patients.DS system showed that 6 patients were at stage I,another 6 patients were at stage Ⅱ and the other 50 patients were at stage Ⅲ.While based on ISS system,15 patients were found at stage Ⅰ,22 patients were at stage Ⅱ and the rest 25 patients were at stage Ⅲ.Meanwhile,the correlation between the WB-MRI infiltrative pattems and DS system as well as ISS system had no significant correlation (P＞0.05).Conclusion Different infiltrative patterns in WB-MRI can predict the prognosis in patients with MM at the time of diagnosis.

Objective To explore the application value of susceptibility weighted imaging(SWI)in measuring brain iron deposition in the diagnosis and the assessment of Parkinson’s disease(PD).Methods Thirty cases with PD underwent head routine magnetic resonance imaging and SWI scanning.The unified PD rating scale(UPDRS)was used to assess the severity of PD.The phase values of substantia nigra (SN),red nucleus(RN),caudate nucleus (CA),globus pallidus(GP)and putamen (PUT)were measured manually on the phase map.The correlation between the phase values of the region of interest(ROI)and the UPDRS scores of PD was analyzed.Results There were no significant differences between the phase values of the less severe body side and those of the more severe body side (SN,P=0.120;RN, P=0.402;CA,P=0.196;GP,P=0.616;PUT,P =0.985).Significant negative correlations were found between the phase values of SN, CA,GP and the UPDRS Ⅲ scores,respectively (SN-UPDRS Ⅲ:r=-0.407,P =0.026;CA-UPDRS Ⅲ:r =-0.424,P =0.02;GP-UPDRS Ⅲ:r=-0.363,P =0.048).Significant negative correlation was found between the phase values of SN and the UPDRSⅤranks (r=-0.373 ,P =0.043 ),while the similar correlation was found between the phase values of CA and the UPDRSⅠ scores (r=-0.367,P =0.046)and the medium negative correlation was found between the phase values of GP and the gait disorder scores of UPDRS Ⅲ(r=-0.41 1,P =0.024).But no correlation was found between the phase values of other ROIs and the UPDRS scores. Conclusion SWI could quantitatively assess the brain iron deposition of the PD patient,which provided reference for clinical diagnosis and assessment of PD.

Objective To observe the lumbosacral plexus nerves by diffusion tensor tractography (DTT) and quantitatively evaluate them by using diffusion tensor imaging (DTI) in healthy volunteers.Methods A total of 60 healthy volunteers (30 males and 30 females) underwent DTI scanning.Mean FA values of the lumbosacral plexus nerves (both sides of lumbar roots L3 to S1,proximal and distal to the lumbar foraminal zone) were quantified.Differences among various segments of lumbar nerve roots were compared with ANOVA test and SNK test.Differences between two sides of the lumbar nerve roots at the same lumbar segment were compared with paired-samples t test.Differences between the proximal and the distal nerve to the the lumbar foraminal zone at the same lumbar segment were compared with paired-samples t test.The lumbosacral plexus nerve was visualized with tractography.Results (1) The lumbosacral plexus nerve was clearly visualized with tractography.(2) Mean FA values of the lumbar nerve roots L3 to S1 were as followings:proximal to the left lumbar foraminal zone 0.202 ± 0.021,0.201 ± 0.026,0.201 ± 0.027,0.191 ±0.016,distal to the left lumbar foraminal zone 0.222 ± 0.034,0.250 ± 0.028,0.203 ± 0.026,0.183 ± 0.020,proximal to the right lumbar foraminal zone 0.200 ± 0.023,0.202 ± 0.023,0.205 ± 0.027,0.191 ±0.017,distal to the right lumbar foraminal zone 0.225 ±0.032,0.247 ±0.027,0.205 ± 0.033,0.183 ±0.021.Mean FA values were significantly different between the proximal nerve to the distal nerve in lumbar nerve roots L3,L4,S1 (t =-9.114-2.366,P ＜ 0.05),but not significantly different in L5 (P ＞ 0.05).Differences were not found between the right and left side nerves at the same lumbar segment (P ＞ 0.05).(3) The whole length of the lumbar roots nerve L3 to S1 can be visualized clearly by using DTT.Conclusions Diffusion tensor imaging and tractography can show and provide quantitative information of human lumbosacral plexus nerves.DTI is a potential tool for the diagnosis of lumbosacral plexus nerve disease.

Objective To identify anatomical characteristics of neurovascular compression associated with trigeminal newralgia(TN).Methods Fifty patients with TN (23 of 50 patients underwent microvascular decompression) and 50 patients without facial pain underwent 3.0 T MRI scanning for analysis of 50 trigeminal nerves ipsilaterai to TN symptoms,50 contralateral to TN symptoms,and 100 in asymptomatic patients.MRI sequences included balanced fast-field echo and 3D MR angiography.Images were fused and reconstructed into virtual cisternoscopy images to determine the degree (severity of compression was defined as follows:1=no compression; 2 =compressed by a vein; 3 =contacted by an artery; 4 =indented by an artery; and 5 =nerve displaced or distorted by an artery) and site of neurovascular compression ( the point of each offending vascular structure:proximal was defined as located in 1/3 length of the cisternal segment of the trigeminal nerve near root entry zone; the place of superior was defined as above the cisternal segment of the trigeminal nerve).Reconstructed MPR images were used to measure nerve length and cross sectional area.The chi-square test was used for all 2 × 2 contingency tables.The t-test was used for dependent samples.The Logistic regression was used for prediction of occurrence of the event of TN.Results Twenty-three of 50 patients with TN underwent microvascular decompression,which confirmed predicted neurovascular relationships in all cases,and 21of 23 patients were pain free after the operation.The incidence of neurovascular compression on asymptomatic nerves ( no.of level 1=79,level 2 =5,level 3 =8,level 4 =8),on nerves contralateral to TN symptoms( no.of level 1=27,level 2 =6,level 3 =9,level 4 =8),and on nerves ipsilateral to TN symptoms(no.of level 1=4,level 2 =12,level 3 =12,level 4 =7,level 5 =15) was 21.0％ (21/100),46.0％ (23/50),and 92.0％ (46/50),respectively.The difference between symptomatic and asymptomatic nerves was significant regarding nerve distortion ( level 4 and 5,x2 =27.0,P ＜ 0.01),the point of compression ( no.of proximal of symptomatic nerves =32,not proximal of symptomatic nerves =14,proximal of asymptomatic nerves =4,not proximal of asymptomatic nerves =17,x2 =14.8,P ＜ 0.01),the place of vascular compression ( no.of superior of symptomatic nerves =36,not superior of symptomatic nerves =10,superior of asymptomatic nerves =5,not superior of asymptomatic nerves =16,x2 =18.0,P ＜0.01) and the mean cross-sectional area of the CPA cistern [ ipsilateral:( 183.9 + 52.5 ) mm2,contralateral:( 217.8 + 58.8 )mm2,t =- 3.04,P ＜ 0.01].Decreased nerve size was observed in patients with TN [ the section area of ipsilateral nerve ( 6.3 ±1.3) mm2,contralateral (7.7+1.6) mm2,t =-4.80,P ＜0.01; length of ipsilateral nerve:(8.0 ±1.9) mm,contralateral:(9.0 + 2.0) mm,t =- 2.64,P ＜ 0.05 ].Conclusions Trigeminal neurovascular compression can occur in asymptomatic patients,but is more severe,more proximal,more superior and with smaller size of cross-sectional area of the CPA cistern in patients with TN.This information may help identify patients who are likely to benefit from microvascular decompression.

Objective The aim of the study was to evaluate the reliability of whole-body MRI(WBMRI)in detecting osseous metastases.Methods Thirty patients verified with malignant tumor by histology were enrolled.All the patients underwent WB-MRI and bone scintigraphy(BS)with a two week interval.Clinical information,conventional MRI and CT images,and follow-up data were collected as gold standard for the diagnosis of bone metastases.The data of 30 patients and 270 segments as study unit respectively were analyzed.The sensitivity and specificity between WB-MRI and BS were compared with McNemar test.Resuits Bone metastases were confirmed in 27 of 30 patients by gold standard.Twenty-five patients with bone metastases were detected by WB-MRI and no false-positive cases.Twenty-seven patients with bone metastases were Nund by BS but having two false-positive oases.With patients as study unit,the diagnostic sensitivity of WB-MRI and BS were both 92.6%(25/27)and the specificity were 100%(3/3)and 33.3%(1/3),respectively.The area under ROC curve of WB-MRI and BS were 0.9630 and 0.6296,respectively(P>0.05).With segments as study unit,119 bone metastases segments were confirmed.The diagnostic sensitivity of WB-MRI and BS were 90.8%(108/119)and 70.6%(84/119)(P<0.01),while the specificity were 98.0%(148/151)and 90.7%(137/151),respectively(P<0.01).The area under ROC curve of WB-MRI and BS were 0.9438 and 0.8066.The former was obviously higher than the latter(P<0.01).Meauwhile.by WB-MRI,3 cases coexisting with brain metastases,4 cases with lung metastases,and 4 cases with hepatic metastases were found.Conclusion WB-MRI was a good tool for screening osseous metastases.

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 investigate the suitable injection rate and dose in multi-slice CT perfusion imaging.Methods Randomized block design was adopted in this study.The treatment factor-contrast medium injection rate was classified into 3,4,5,6 and 8 ml/s;thesubjects were divided into 5 blocks grouped by contrast medium injection dose: 0.5,0.75,1,1.25 and 1.5 ml/kg.25 Beagles wererandomly enrolled to undergo cerebral CT perfusion imaging.After post processing,time to peak(TTP) and rise value(RV) were measured in superior sagital venous.Results Injection rate had a significant effect on TTP of superior sagital venous.There was no significant difference among group 5,6 and 8 ml/s.Compared with 8 ml/s,TTP of superior sagital venous was prolonged when injection rate 3,4 ml/swere adopted.Injection dose had a significant effect on RV of superior sagital venous.There was no significant difference among group 1,1.25 and 1.5 ml/kg.In comparison with 1 ml/kg,RV of superior sagital venous was prolonged when injection dose 0.5 and 0.75 ml/kg were adopted.Conclusion The quality of cerebral CT perfusion imaging is well enough even injection rate as low as 5 ml/s or injection dose as few as 1 ml/kg.

Objective To evaluate the energy metabolism of normal muscle in different age group.Methods Noninvasive 31P-MRS was acquired from quadriceps muscles in healthy people including 10 adults and 6 juvenile.Peak areas were standardized for longitudinal saturation and coil inhomogeneity.The concentration of phosphomonoesterase(PME),inorganic phosphate(Pi),phosphodiesterase(PDE),phosphocreatine(CrP)and adenosine triphosphate(ATP)was determined from spectra.Concentrations of adenosine diphosphate(ADP)and phosphorylation potential(PP)were calculated from the biochemistry reaction equilibrium.Enzymatically active magnesium ATP complex Mg-ATP and pH value were determined from relative chemical shift.Results Normal muscle had prominent high energy phosphate peaks,the mean concentration of CP and ATP was 24.76 and 18.38 mmol/kg in adults,25.52 and 21.36 mmol/kg in young subject.In comparison with adult group,young subjects had lower PDE and higher ATP values.pH value,magnesium ATP and total magnesium were higher in young subjects too.Pi,CP,ADP,PP,free Mg2+ and free ATP concentration were similar in both group.Conclusion High energy compounds were slightly higher in juvenile subjects.31P-MRS is a noninvasive technique to evaluate energy metabolism in different age group.