Visceral abdominal adiposity tissue volume quantification using noninvasive MRI in prediction of type 2 diabetes / 中国医学影像技术

Objective To investigate the feasibility of utilizing visceral abdominal adiposity tissue (VAT) volume quantification using MRI to predict type 2 diabetes mellitus (T2DM).Methods Forty-eight subjects including 15 T2DM (T2DM group),17 impaired glucose tolerance (IGT,IGT group) and 16 normal glucose tolerance (NGT,NGT group) were enrolled in this study.All subjects underwent upper abdominal iterative decomposition of water and fat with echo asymmetry and least square estimation-image quantification (IDEAL-IQ) MRI scanning.VAT volume of the second and third lumber vertebral body ranges (VATV L2,VATV L3),sum of VATV L2 and L3 (total VATV),hepatic and pancreatic fat were measured in fat fraction mapping of T1WI IDAEL-IQ sequence on post-processing workstation.The accuracy of predicting T2DM using VAT was evaluated by Logistic regression equation via ROC curve.Results The mean of VATV L2,VATV L3 and total VATV in T2DM group were significantly higher than those of IGT group and NGT group (P＜0.05),while there were no significant difference of these metrics between IGT group and NGT group (P＞0.05).Taking 460.34 ml as the cut-off value for VATV L2 to predict T2DM,sensitivity was 73.33％,specificity was 75.76％ and accuracy was 75.00％,respectively.Taking 429.46 ml as the cut-off value for VATV L3 to predict T2DM,sensitivity was 86.67％,specificity was 72.73％ and accuracy was 77.08％,respectively.Taking 887.83 ml as the cut-off value for total VATV to predict T2DM,the sensitivity,specificity and accuracy were 86.67％,72.73％ and 77.08％,respectively.Only VATV L3 was enrolled by Logistic regression equation (P=0.01,OR=1.01),and the sensitivity,specificity and total accuracy of prediction for T2DM were 80.00 ％,88.20 ％,and 84.40 ％,respectively.Conelnsion It is feasible to utilize VAT volume quantification with MRI to predict T2DM.VATV L3 is a better predictor.

Single energy metal artifact reduction technique in the evaluation of postoperative tumor endoprostheses in the knee joint / 中华放射学杂志

Objective To evaluate the effect of the single energy metal artifact reduction (SEMAR) algorithm with a 320 multi-slice computed tomography (MSCT) volume scanner in patients with knee tumor prostheses.Methods From November 2015 to March 2016,23 consecutive patients with knee tumor prostheses who underwent a 320-MSCT scan were collected.And the raw data were reconstructed using two different methods:conventional iterative reconstruction (IR) alone and IR associated with SEMAR.The ROI were objectively and subjectively assessed at osteotomy level and articular level,and the Wilcoxon signed rank test was used for them.Results Compared with IR,objectively,artifact index (AI) values of the osteotomy level decreased 44.8％ to 74.1％ and that of the articular level decreased 73.2％ to 93.2％;subjectively,the scores of image quality of two levels were increased 0.5 to 2.0 scores and 1.0 to 4.0 scores by SEMAR respectively.The objective and subject image quality of periprosthetic structures were all significantly improved by the SEMAR algorithm (P＜0.05).Conclusion The SEMAR algorithm significantly reduced the metal artifact of knee tumor prostheses,improved the image quality of periprosthetic structures and may increase diagnostic confidence of prosthetic complications in patients with modular knee tumor prostheses,especially at the osteotomy level.

Value of visualization of the intraparotid facial nerve and parotid duct using a micro surface coil and three-dimensional fast imaging with steady state precession with fat-suppression sequence / 中华放射学杂志

Objective To explore the value of small surface coil combine with three-dimensional fast imaging with steady state precession and fat-suppression (3D-FISP-FS) sequence in displaying intra-parotid facial nerves segment and parotid ducts.Methods The parotid regions of 18 healthy volunteers who were excluded any parotid diseases were scanned by head&neck coil (36 sides) and 4 cm small surface coil (32 sides) combined with 3D-FISP-FS sequence prospectively. The obtained original images were treated through MIP, MPR and CPR, The MRI signal characteristics of parotid region structure, the subjective score of image quality, the signal intensity ratio (SIR) of facial nerve/parotid tissue (SIR N) and parotid duct/parotid tissue (SIRD) was calculated, and the displaying rates of the facial nerves and parotid ducts were observed. Wilcoxon matched-samples signed rank sum test was used to compare the scores of head&neck coil and small coil 3D-FISP-FS sequence images, paired t test was used to compare SIRN, SIRD of the two groups, Chi-square test was used to compare of the displaying rate of the facial nerves and parotid ducts in two groups. Results Eighteen volunteers were successfully performed MRI scan of parotid gland. On 3D-FISP-FS sequence images, the parotid gland was showed slightly low signal intensity, muscle tissue was showed medium signal intensity, the vessels were showed slightly high or high signal, parotid segment of facial nerve was showed tortuous line-like high signal intensity, and parotid duct was showed curve high signal intensity, lymph nodes were showed kidney shaped, oval or spindle shaped high signal intensity structures. The subjective scores for head and neck coil and coil images were (2.0 ± 0.9) and (1.5 ± 0.7) respectively, and the difference was statistically significant (Z=-2.714, P=0.007), image quality of small coil group was better than that of head and neck coil group. The SIRN of the two groups was 1.7±0.8 and 2.1± 1.2 respectively, and the SIRD was 1.8±0.7 and 2.5±1.7 respectively, which showed a statistically significant difference between the two groups (t value was 2.978, 2.427 respectively, P value was 0.006, 0.031 respectively).All facial nerve trunks could be displayed by head and neck coil and small coil. On head and neck coil images, 25 sides of temporofacial truck, 15 sides of cervicofacial truck, 17 sides of temporofacial branches, 11 sides of cervicofacial branches, 16 sides of the parotid duct could be displayed. On small coil images, 30 sides of temporofacial truck, 28 sides of cervicofacial truck, 26 sides of temporofacial branches, 23 sides of cervicofacial branches, 27 sides of the parotid duct could be displayed, which showed a statistically significant difference (P<0.05). Conclusion Small surface coil performed better in parotid MR imaging with 3D-FISP-FS sequence than that of head and neck coil, which can simultaneous clearly display the trunk and branches of the intra-parotid facial nerves and parotid ducts.

MRI features of different sizes of small coil using a water phantom / 中华放射学杂志

Objective To explore the imaging characteristics of different sizes of MR small surface coil.Methods A water phantom with NiSO4· 6H2O for Siemens was scanned with 4 cm,7 cm and 11 cm small surface coils in Siemens 3.0 T MR system.T1WI,T2WI,three dimensional reversed fast imaging with steady state precession with diffusion-weighted(3D-PSIF-DWI) and three dimensional fast imaging with steady state precession and fat suppression(3D-FISP-FS) images were obtained.The imaging area,signal intensity (SI),standard deviation (SD) and signal-to-noise ratio (SNR) variations of different depths (from the near to the distant) were measured and compared.Curves according to the SI and SNR data were draw.SI and SNR characteristics of images obtained by L11 separately and used together with spine matrix coil were compared by using signed rank sum test.Results The signal intensity of images scanned by 4 cm,7 cm small surface coil decreased gradually in the depth of 0.2 to 2.2 cm,maintain good signal uniformity in the depth of 2.2 to 4.2 cm,and the signal intensity obtained by 11 cm coil maintain good signal uniformity in the depth of 5.2 cm.The optimum imaging widths of 4 cm,7 cm and 11 cm coil were about 7.0,8.5 and 11.0 cm.As the diameter of the coil increased,the imaging width and depth increased,but the received noise also increased.The SNR gradually reduced from the center to the edge of the coils.The imaging area increased but the local SNR decreased when using L11 coil combine with spine matrix coil,which showed a statistically significant difference (Z=-2.354,P=0.019).Conclusions A suitable size of small surface coil should be chosen according to the location and size of the organ or lesion before clinical MR examination.Other coils should be turned off to improve the SNR.

Construction of pediatric bone and joint system diagnostic imaging online course by blackboard platform / 中华医学教育探索杂志

Diagnostic Imaging Pediatric bone and joint system was a sub-branch of professional courses.The content was more difficult and learners were not relaxed to master the knowledge alone.It was easy,across time and space,resource sharing and interactive to operate on blackboard teaching platform.We can better accomplish teaching and learning task with pediatric bone and joint diagnostic imaging online course constructed by blackboard platform.

The MRI study of supraparamagnetic ironic oxide loaded polymeric nano-vesicles in human colonic carcinoma xenograft in nude mice / 中华放射学杂志

Objective To synthesize the hydrophobic supraparamagnetic ironic oxide(SPIO) loaded and hydrophilic SPIO loaded polymeric nano-vesicles and to investigate the feasibility of using hydrophobic SPIO loaded and hydrophilic SPIO loaded polymeric nano-vesicles to display the tumor in MRI in vivo through animal experiments. Methods The polymeric nano-vesicles were prepared from poly (D, L-lactic acid) (PDLLA) and poly (ethylene glycol) (PEG) by a multiple emulsion/solvent evaporation method.The hydrophobic SPIO and hydrophilic SPIO were loaded in the polymeric nano-vesicles respectively.Eighteen nude mice models with human colorectal carcinoma xenograft were established. They were divided equally into three groups (n = 6). The three groups of nude mice models were injected with water-soluble SPIO, hydrophobic SPIO loaded and hydrophilic SPIO loaded vesicle via the mice caudal vein respectively.Dynamic MRI scan were performed in all the mice models. T2WI signal intensity and T2 relaxation time were measured in the tumor, liver and muscle by using T2 mapping software. ANOVA of repeated measurement was used to analyze if there were significant differences of signal intensity changes among the three groups, while Bonferroni method was used for pair-wise comparison. Results On T2 WI, tumors showed decrease in signal intensity after hydrophobic or hydrophilic SPIO loaded polymeric nano-vesicle injection, while no signal intensity decrease was found in the tumor after water-soluble SPIO administration. The maximum percentage of signal intensity decrease in tumor caused by hydrophobic SPIO loaded and hydrophilic SPIO loaded vesicle were 11.00%, 11.40%, respectively. There was statistical significant difference of signal intensity changes among these three groups (F = 10. 96, P ＜ 0. 01). The decrease in signal intensity in the groups with hydrophilic or hydrophobic SPIO loaded polymeric nano-vesicles injection were more pronounced as compared with that of water-soluble SPIO (P ＜ 0. 05), but there was no significant difference in signal intensity decrease between the groups of hydrophilic and hydrophobic SPIO-loaded polymeric vesicles injection (P ＞0. 05). The three agents could lead to signal intensity decrease in the liver. The maximum percentage of signal intensity decrease in liver caused by water-soluble SPIO, hydrophobic SPIO loaded and hydrophilic SPIO loaded vesicle were 32. 85%, 52. 77%, 56. 89%, respectively. There was statistical significant difference between these groups (F = 161.18, P ＜ 0. 01) . The groups of injecting hydrophilic and hydrophobic SPIO loaded polymeric nano-vesicles had the more obvious signal decrease than the one with water-soluble SPIO (P ＜ 0. 01). Hydrophilic SPIO loaded polymeric nano-vesicles exhibited more signal intensity decrease than hydrophobic SPIO loaded polymeric nano-vesicles (P ＜ 0. 01). All three agents could not lead to T2WI signal decrease in the muscle, and there was no significant difference in signal change on T2 WI among three groups (F = 0. 59, P ＞ 0. 05). Conclusion SPIO loaded polymeric nano-vesicles can cause significant T2WI signal loss in human colonic carcinoma on MR imaging in vivo. It can be used as tumor imaging contrast agents.

MR imaging of short T2 components with three dimension ultrashort echo time double echo pulse sequence:investigation of factors affecting imaging quality / 中华放射学杂志

Objective To investigate the effect of imaging parameters and postprocessing methods on the quality of MR imaging of short T2 components with 3D ultrashort TE (UTE) double echo pulse sequence. Methods 3D UTE double echo pulse sequence was performed on dry human femoral specimen and the tibial diaphyses, knee joints, and tendons of ankles of a group of healthy volunteers. To investigate the effect of different trajectory delays of the imaging system(-6, -3, -2, - 1,0, 1,2, 3 s), different flip angles(4°, 8°, 12°, 16°, 20°, 24°), different TEs (0. 08, 0. 16, 0. 24, 0. 35 ms)and different postprocessing methods(difference imaging of subtracted volume and non-volume UTE)on the 3D UTE MR imaging quality, the SNR and CNR were calculated and compared, and the artifacts of the images were analysed. Results The cortical bone, periosteum, tendon and meniscus showed high signal intensity on the images of UTE pulse sequence. The best SNR was acquired with 2 s trajectory delay. The best flip angle was 8° to 12° for the human UTE imaging in vivo. The highest CNR was obtained from the TE of 0. 08 ms. The longer the TE was, the more artifacts appeared. The SNR of difference imagewas improved when image subtraction was performed afer multiplanar reconstruction (MPR) of the primary double echo images.Conclusions The short T2 components show high signal intensity on the MRI of 3D UTE double echo pulse sequence. The imaging quality can be improved by shortening TE, using appropriate flip angle and performing subtraction for difference image after MPR of the primary double echo images.

CT diagnosis of criss-cross heart / 中华放射学杂志

Objective To probe the clinical application of CT in the diagnosis of criss-cross heart(CCH).Methods Five patients with CCH confirmed by operation were retrospectively analyzed.Enhanced 64-slice spiral CT was performed in 2 patients and enhanced single-slice electron beam CT was performed in 3 patients.Three dimensional reconstructions were applied for the fully display of anatomic malformations,and the results were compared with that of echocardiogram and angiocardiogram with Chi-square test Results(1)Visceroatrial situs solitus,twisted and concordant atrioventricular connection,horizontally oriented ventricular septum,ventricular septum defect and pulmonary stenosis were found in all patients on CT.The ventriculoarterial connection was discordant,including double-outlet right ventricle in 4 patients and complete transposition of great arteries in 1 patient In addition,associated anomalies including persistent left superior vena cava(n=2),coarctation of the aorta(n=1)and right aortic arch with right descending aorta(n=1)were detected as well.(2)Total 33 anomalies in 5 cases were found during operation.The diagnostic accuracy of CT,angiocardiogram and echocardiogram was 93.9%(31/33),81.8%(27/33)and 54.5%(18/33)respectively.There was a significant difference between CT and echocardiogram(X~2=13.39,P＜0.01),and no significant difference between CT and angiocardiogram(X~2=1.29,P＞0.05).Conclusion CT is an excellent imaging technique for the diagnosis of CCH.

CT diagnosis of cardiac rhabdomyoma in childhood / 中华放射学杂志

Objective To investigate the CT findings of cardiac rhabdomyoma in childhood. Methods Five children with cardiac rhabdomyoma confirmed by operation was retrospectively analysed. Enhanced electron beam CT (EBCT) was performed in 4 children and enhanced 64-slice helical CT (MSCT) scan was performed in 1 infant. Three dimensional reconstruction was applied for the full display of the lesions based on the transverse section images. Results ( 1 ) Multiple masses or nodules originated from atrioventricular septum were observed in 4 children including 1 nodule from the anterior walls of the left and right ventricles. A mass was derived from the mitral valve in 1 infant (2) The CT value of the lesions after enhancement ranged from 80 to 180 HU and was similar to neighbouring left ventricular myocardium. (3) The ventricular outlet obstruction was found in 3 children including 1 infant with pericardial effusion and pulmonary inflamation of the right lower lobe. Conclusion The rhabdomyoma should be considered first when masses or nodules originated from atrioventricular septum and with the enhancement similar to neigbouring left ventricular myocardium in children.

A clinical-radiologic-pathologic analysis of telangiectatic osteosarcoma / 中华放射学杂志

Objective To study the clinical, radiologic and pathologic characteristics and diagnostic methods of telangiectatic osteosarcoma for further improving the diagnostic ability.Methods The data of 10 patients with histologically proved telangiectatic osteosarcomas were retrospectively reviewed, and the clinical, radiologic and pathologic characteristics were further analysed in combination with the literature.All 10 patients were examined with X-ray and MRI, and 2 patients with CT.Results Telangiectatie osteosarcomas originated from inferior femur in 5 patients, femur neck in 1 patients, superior humerus in 2 patients and superior segment of tibia in 2 patients.The lesions showed osteolytic bone destruction on X-ray films (n = 10) and CT images ( n = 2), with mild bone expansion in 4 patients.The majority of the edge of the destroyed bone areas was unclear but without sclerotic rim.There were Codman's triangle and soft tissue mass in each patient but no obvious neoplastic bone forming.On MRI, all the lesions were mostly or completely constituted by the multiple cysts with periostnal reaction, and several scatteredly smaller liquid-liquid levels were found within cystic cavity in 7 patients.In all 10 cases, there were pathologic hemocoele similar to aneurysmal bone cysts (ABC), but malignant tumor cells and some neoplastic bones were found in cystic walls or septations.Only a small number of neoplastic bone tissue were seen by microscopy in 6 patients.Conclusions The radio-pathologic characteristics of telangiectatic osteosarcoma include the similar imaging findings of ABC, the common growth patterns of malignant tumors,and the pathologic hemocoele, malignant tumor cells within cystic wails or septations.The comprehensive analysis of clinical, radiologic and pathological data may help clinicans to make a correct diagnosis for telangiectatic nsteosareoma.

Discriminant function analysis for pericolic infiltration in colorectal cancer with dynamic enhanced 64-slice spiral CT / 中华放射学杂志

Objective To evaluate the efficacy of discriminant function analysis for pericolic infiltration in colorectal cancer on enhanced 64-slice spiral CT and to improve the diagnostic accuracy and specificity of pericolic infiltration. Methods Dynamic enhanced 64-slice spiral CT was performed in 49 colorectal cancer patients (49 masses in total) before surgery. One or two slices were selected for each mass, with a total of 96 slices. The 96 slices were classified into two groups (pericolic infiltration or nonpericolic infiltration group) according to pathological data. Discriminant analysis was performed on the CT values between the mass and the corresponding pericolic tissue 5 mm from the mass at different time points as follows; 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, and 75 s. The discriminant function was calculated, and the pericolic infiltration determined by discriminant function and CT morphology were compared with the pathological results. The CT values in pericolic and non-pericolic infiltration groups at different enhancement time points were assessed using analysis of variance. Results The mean CT values ranged from (43. 6 ±7. 8) HU to (52. 3 ±0. 8) HU in the pericolic infiltration group, and ranged from (100.4±20.3)HU to(116.2±21.4)HU in the non.perieolic infiltration group.At 20 s and 40 s,the mean CT vshle8 were(43.6±27.8)HU and(50.9±27.8)HU in the perleolic infiltration group, (102.0±16.9)HU and(116.2 ±21.4)HU in the non-perieolic infiltration group,respectively.The mean CT value in the pericolic infiltration group was significantly lower than that in the non-pericolic infiltration group at all contrast enhancement time points(F=6.278,P<0.01).A diseriminant function Was obtained as follows:D=-3.450+0.023Xl±0.017X2-0.00lX12-0.001X22+0.002X1×X2. Based on the CT morphology of colorectal cancer,69 slices were identified correctly and 27 slices were fulsely interpreted.the sensitivity.speeificity and accuracy for perieolic infiltration determination were 82.5%,64.3%and 71.9%.respectively.Based on diseriminant function,85 slices were identified correctly and 11 slices were falsely interpreted.the sensitivity,specificity and accuracy were 85.0%.91.1%and 88.5%,respectively.Conclusion The discriminant function with dynamic enhanced 64-slice spiral CT can improve the diagnostic accuracy and specificity of perieolic infiltration in eolorectal cancer patients.

CT diagnosis of cardiac lipoma / 中华放射学杂志

Objective To investigate the application of CT in the diagnosis of cardiac lipoma.Methods Retrospective analysis of 6 patients with cardiac lipoma confirmed by operation and pathology was done. Four patients had singles slice electron beam CT plain and contrast and movie scan. Two patients had 64-slice CT plain and enhanced scan. Results (1) One patient was isolated intracavitary lipoma in the right artium, 1 patient was isolated intrapericardial lipoma and 4 patients were intramural lipomas. Of the 4 intramural lipoma, 2 were infiltrative lipomas located in the left ventricle wall or the right ventricle and septum, 2 patients were isolated in the atrio-ventricular septums. (2) CT and three-dimensional reconstruction could depict the location, shape, size, margin and characteristic fat density of lipoma,indicating the diagnosis and classifications. The displacement of coronary artery, pulmonary inflammation and effusions of pericardium and pleural cavity could also be revealed. Conclusion Cardiac lipoma can be accurately diagnosed and classified by CT.

Absolute quantification of calf muscle metabolites by proton 1H-MR spectroscopy / 中华放射学杂志

Objectiye To measure longitudinal (T1) and transverse (T2 ) relaxation time of metabolites in m. soleus (SOL) and m. tibialis anterior TA of healthy volunteers at 3.0 T through 1H-MRS and optimize measurement protocols. Methods Altogether 24 healthy volunteers were recruited in the study. All subjects signed a letter of informed consent. After divided into 2 groups randomly by the table of random number, 1H-MRS measurements with stimulated echo acquisition mode (STEAM) sequence were undertaken in SOL and TA separately. Progressive saturation method was used for T1 measurement. Spectra with 8 different TRs (770,900,1000, 1100,1200,1500,2000 and 3000ms ) were acquired with TE=20 ms.T2 time was measured by changing TE. Altogether 8 TEs (20,30,45,60,90,135,200 and 270 ms) were used with TR = 3000 ms. Metabolites' concentration was calculated through T1 and T2 correction using water as internal reference. The t test was used for statisties. Results Altogether 22 groups of data were gained ( 12 for SOL, 10 for TA ) . T1 value of water, Creatine-CH3 ( Cr3 ), Trimethyl amonium ( TMA ),extramyocellular lipid (EMCL) and intramyocellular lipid (IMCL) in SOL were ( 1384. 0 ± 36. 9 ),( 1064. 0 ± 167.0), (964. 2 ± 144. 0 ), ( 373.0 ± 46. 8 ), ( 374. 7 ± 20. 6) ms respectively and T2 value were (26.5 ±1.2), (100.2±19.3), (149. 1 ±32.7), (81.4±5.2), (84.7±4.2) ms. InTA T1 value of water, Cr3, TMA, EMCL, and IMCL were ( 1307. 0 ± 24.4), (945.7 ± 132. 0), (968.3 ± 127. 0),(372. 7 ± 39. 2), (412. 8 ±80. 2) ms respectively and T2 value were (27. 1 ± 0. 9), (135.3 ± 18. 2 ),(62.1 ± 6. 0), ( 84. 3 ± 4. 0 ), ( 90. 7 ± 3.2 ) ms. After corrected by the calculated relaxation times, the concentrations of Cr3 in SOL and TA were (33. 1 ± 3.7) and (31.7 ± 3. 1 ) mmol/kg respectively, TMA (35.2±3.2) and (32.9 ±5.2) mmol/kg, EMCL (12.2 ±5.0) and (8.9 ±4.9) mmol/kg, IMCL (9. 0 ± 2. 4) and (3.0 ± 0. 8 ) mmoL/kg. IMCL in TA was much lower than SOL with statistical significant ( t = 8. 044, P < 0. 01 ), the difference between other metabolites were not statistically significant( t = 0. 926,1. 264, 1. 542, P > 0. 05 ) . Conclusions Accurate relaxation time was measured at 3.0 T of the metabolites in skeletal muscles of healthy adult human. After corrected by the relaxation times, the absolute concentrations calculated were consistent with the reported results. Quantitative knowledge of muscle NMR relaxation time was a prerequisite for absolute quantification of metabolites using the 1H-MRS and also was useful for optimizing measurement protocols.

Evaluation of angiogenesis of VX2 soft tissue tumor by arterial spin labeling perfusion imaging / 中华放射学杂志

Objective To evaluate the relationship between the blood flow values generated from MR arterial spin labeling (ASL) perfusion imaging and pathologic indicators of angiogenesis including microvascular density (MVD) counts and vascular endothelial growth factor (VEGF) expression levels of VX2 carcinoma in rabbit soft tissue. Methods VX2 tumor was inoculated in the muscular tissue of right posterior limbs of 18 healthy New Zealand white rabbits ,on which arterial spin labeling perfusion imaging was performed by using flow sensitive alternating inversion recovery pulse sequence 3 to 4 weeks later. Arterial spin labeling images were transferred to an independent computer for post-processing and blood flow (BF) maps were generated from them. BF values were measured in 2-4 regions of interest (ROIs) for each tumor. The rabbits were sacrificed after MR imaging. The gross specimens of tumors were obtained and tumor tissues were taken from the non-necrotic regions corresponding to ROIs on BF maps. Immunohistochemical staining of the specimens was performed by using CD31 monoclonal antibody to calculate MVD counts, using VEGF antibody to calculate VEGF expression levels. Correlation between BF values and MVD counts as well as between BF values and VEGF expression levels was evaluated using Spearman correlative analysis.Results On BF maps, viable tumor tissues showed high BF values compared with muscle, but there were areas without blood perfusion in some tumors. Under microscope, the microvessels positively stained by CD31 appeared as light brown areas, and the cells positively staied by VEGF showed reddish brown areas within their cytoplasm. Totally 39 pieces of VX2 tumor tissue were analyzeed There was a significant positive correlation between the BF values(M =6. 4 ml · 100 g-1 · min-1 ) and MVD counts(M =6. 8) (r = 0. 906,P ＜ 0. 01 ), and no significant correlation between BF values and VEGF expression levels ( M = 8％ ) ( r =0. 116, P=0.483). Conclusion BF value can be used in evaluating angiogenesis of soft tissue tumor through its reflection of MVD counts, and thus may be helpful in evaluating the prognosis of soft tissue tumor and making plan for their treatment.

Parameters optimization of diffusion tensor MR imaging of the human calf at 3 tesla / 中华放射学杂志

Objective To demonstrate the feasibility of DTI in human calf with body phased-array coil and surface coil of spine as receiving coil on 3 T system, and to optimize the parameters of sequence, including slice thickness and b-value. Methods Fifteen healthy volunteers were recruited in this study and randomly divided into three groups. The DTI sequence for head was performed on calf in the first group (5 cases), and the sequence parameters were optimized based on the deficits of the raw and the post-processed DTI images. Then, different slice thickness were applied in the senond group (5 eases) to optimize the slice thickness, and this optimized parameter with the highest score based on quality of the post-processed DTI images was applied in the next step. Finally, different b values were applied in the last group to optimize this parameters. The b value with the highest score based on the quality of the pest-processed was the proper one. Results Three problems existed in the raw and the pest-processed images, when the DTI sequence for brain was used for the calf. First, the SNR of raw images is extremely low. Second, the muscle were unclear on the image with parts of signal lose, especially in the anterior tibialis muscle. Finally, the artifacts due to chemical shift and ghost are quite serious. The scores for muscle display quality with slice thickness of 4 mm , 5 mm and 6 mm were (7.0±0. 0), (8.6±0. 9) and (9.0±0. 0) score respectively, the signal less scores were (5.0±0. 0) and ( 12. 8±2. 6) and ( 13. 8±2. 2) score respectively, and the general score were (22. 0±0. 0) and (30. 1±3.8) and (31.0±4. 1 ) score respectively. The differences of above scores were significant among different slice thickness (F-value were 21. 000 and 30. 544 and 12. 390 respectively, P <0. 05 ). The muscle displaying quality, signal loss and general scores were lowest in group with 4 mm slice thickness (q-value were 4. 896.6. 120,6. 327,7. 138,3. 863 and 4. 043, P < 0. 05 ) o The scores of muscle display quality, signal loss and general for b =400 s/mm2 were (9. 0±0. 0), ( 14. 0± 2. 2 ) and ( 33.0±2. 2 ) score respectively, which were lower than those with b = 800 s/ram2 [(7.0±0.0), (6.2±2.2), (21.8±3.4) score] and b=1000 s/mm2[(7.0±0.0), (5.0±0.0), (20.6±2.2) score] (q-value were 3.873,3.873,6.650,7.672,7. 101 and 5.917, P <0.05)o The scores of muscle displaying quality, signal loss and general for b =600 s/mm2 were (8.2±1.1 ), ( 13.0± 2. 3) and ( 30. 8±3. 8 ) score respectively, which were higher than those with b = 800 s/mm2 and b= 1000 s/nun2 (q-value were 3.873, 3.873, 5.797, 6.820, 5.326 and 5.917, P <0.05).There is no significant difference between b = 600 s/ram2 and 400 s/ram2 ( q-value were 2. 582 and 0. 852 and 1. 775, P > 0. 05 ). Conclusion Our preliminary findings indicate that it is feasible to perform DTI on human calf with 3 T MR. With body phased-array coil and surface coil of spine as receiving coil, the DTI sequence were optimized to acquire enough SNB with slice thickness of 5 mm and b-value of 400 s/mm2.

CT pulmonary angiography using 64-row multi-slice spiral CT: a comparative study in low tube voltage setting combined with personalized contrast agent application / 中华放射学杂志

Objective To investigate the feasibility of the low tube voltage setting and personalized contrast agent application in 64-row multi-slice spiral CT pulmonary angiography.Methods Ninety patients with high risk of pulmonary artery embolism were sequentially enrolled in the study and divided into 3 groups employing completely randomized design: (1) Regular group included 30 patients using 120 kV and fixed dose of 70 ml contrast agent, (2)Another 30 patients were in 120 kV group, using 120 kV and the contrast amount was determined according to the patient weight (1.0 ml/kg), (3) The remaining 30 patients were included in 100 kV group, using 100 kV and the contrast amount was also determined according to the patient weight(1.0 ml/kg).Administration of contrast agent was completed within 20 seconds for all the patients, followed by 20 ml of saline.The objective and subjective indexes for assessing CT image quality, CT dose index volume (CTDIvol) and effective received dose (ERD) were compared between 120 kV group and 100 kV group; then the contrast media volume, injection rate, objective CT image indexes and subjective indexes for image quality was compared between the 100 kV group and regular group.The variance analysis and post hoc test were employed for the statistical analysis.Results Compared with 120 kV group(3.4± 0.7), the image quality of 100 kV group(5.2±1.8)had higher noise(52.9%), but subjective index for the image quality demonstrated no differences(q=0.272 ,P=0.063)in mediastinum window while CTDIvol and ERD decreased for 34.9%[(9.5±0.0) vs (14.6±0.0) mGy]and 36.8%[(3.8±0.6) vs (2.4± 0.4) mSv].The mean CT values on pulmonary artery of 100 kV group[(269.2±54.7) HU]were 13.4% (31.8/237.4) higher than the 120 kV group[(237.4±62.9) HU], but there was no statistical differences eornpared to normal group(q=0.172,P=0.260).Conclusion Using low kV setting (100 kV) to reduce radiation dose is proved to be effective and feasible in 64-MSCT pulmonary angiography.Personalized contrast agent injection has clinical application value for specific patient group.

MRI with microscopy coil of the proximal interphalangeal joints: preliminary study / 中华放射学杂志

nal surface coil,and it can be a promising method to diagnose interphalangeal joints lesions.

MRI evaluation of the histopathological characteristic of limb soft-tissue aggressive fibromatosis / 中华放射学杂志

Objective To assess the value of using MRI to evaluate the histopathological characteristic of limb soft-tissue aggressive fibromatosis (AF). Methods The MBI findings and histopathological data of 20 patients with AF were obtained and analyzed. The difference between the different signal regions in AF were compared of signal intensity in T1-weighted images, T2-weighted images and degree of enhancement. The data were processed with paired t test. The histopathology of different signal regions was observed in 6 cases on HE stain and Masson trichromic stain of AF specimen. Results (1) AF predominantly originated from the skeletal muscles (19/20), presenting as Iobulated mass with infiltrative growth(20/20) ;(2) A few claw-shaped neo-arteries(7/7) were delineated in the periphery of the mass in the 3D DCEMRA images as well as the mild tumor staining(7/7) ; (3) Based on the MRI findings, the porenchyma of 20 AF was divided into two distinct regions of structure: region Ⅰ and region Ⅱ. Region Ⅰ presented as hypointensity on both T1-weighted and T2-weighted images and no enhancement after i. v. administration of contrast. Region Ⅱ presented as mild hyperintensity on T2-weighted images and iso- or hypointensity on T1-weighted images and marked enhancement; (4) The signal intensity in T1-weighted images, T2-weighted images and degree of enhancement was 0. 10 ± 0. 02,0. 24 ± 0. 03, and ( 5.22 ± 0.42)% in region Ⅰ , respectively; and 0.79±0.04,3.05±0.08 and(151.5±8.61)% in region Ⅱ, respectively. The differences between region Ⅰ and region Ⅱ were statistically significant of signal intensity in T1-weighted images( t = 67. 37 ), and signal intensity in T2-weighted images( t = 196. 56) and degree of enhancement(t =76. 62) (P <0. 01 ) ; (5) Histologically, AF was composed of fibroblasts, fibrecytes and bundles of collagen fiber. On Massen triehromie stain, region Ⅰ was stained blue, being proven the mature collagen fibers. Region Ⅱ was predominantly composed of fibroblasts, fibrecytes and was not stained. Conclusion The region Ⅰ and region Ⅱ are the characteristic MRI manifestations of AF, and MBI precisely reflects the histopathological and biological feature of the tumor.

Evaluation of intra-cellular lipid of skeletal muscle by 1H-MR spectroscopy: in vivo and phantom study / 中华放射学杂志

Objective To elucidate the spectrum of lipid peaks in 1H-MRS of skeletal muscle and it's interpretation,to investigate the utility of 1H-MRS in evaluating intramyecellular lipid (IMCL).Methods 1H-MRS was acquired in vivo on tibialis anterior muscle (TA) and soleus muscle (S) on 5 healthy volunteers.The spectrum of the lipid peak between 0.80 and 1.80 ppm was observed with different angle between the long axis of the calf and B0.Ex vivo phantom was an cluster of capillary tubers filled with soybean oil and fat emulsion,simulating the extramyecellular lipid (EMCL) and IMCL,respectively.The spectra of the lipid peaks were compared using different angles between the phantom and Bo field.Results The lipid spectrum split to 3 to 4 peaks between 0.80 and 1.80 ppm on calf muscles,with 0.20 to 0.30 ppm interval between each neighbouring peak.The methylene peak of EMCL shifted to the right when the angle between long axis of the calf and B0 increased.The phantom could simulate the spectrum of 1H-MRS of the muscle,presenting two peaks with 0.20 to 0.30 ppm chemical shift difference between 0.80 and 1.80 ppm.They are methyl triglyceride and methylene,representing IMCL and EMCL,respectively.The peak splitting could be attributed to the high ordered muscle fibers and their chemical shift difference between inta-and extra-cellular distribution.The interval of IMCL and EMCL peaks attenuated when the angle between the muscle fiber and B0 increased from 0 to the magic angle(54.7°).Conclusion On 1H- MRS spectrum,the peak of the EMCL and IMCL splits.This indicated that 1H-MRS is an applicable method to detect IMCL noninvasively.TA is an optimizing muscle for 1H-MRS study.

Pancreatic and renal involvement in von Hippel-Lindau disease: imaging findings / 中华放射学杂志

Objective To analyze the imaging features and to enhance the understanding of pancreatic and renal involvement in yon Hippel-Lindau disease (VHLD). Methods CT and MRI appearances and clinical data of six patients with pancreatic and renal involvement in VHLD were studied retrospectively.Six patients underwent CT scanning, and two of them also had MRI.Results Pancreatic cysts found in all six patients varied from several small cysts to cystic replacement of the entire gland.Calcifications were detected in four patients. Multiple bilateral renal lesions were detected in six patients.The renal lesions were classified as cystic, cystic with solid components and solid.Multiple combined renal lesions were found in five patients, and multiple simple cysts in one patient.Unilateral nephrectomy was performed in two patients, and the renal masses were diagnosed as clear cell carcinoma by pathology.Bile carcinoid was found in one patient, and retroperitoneal metastasis in another.Conclusion Multiple pancreatic cysts and/or multiple and bilateral combined renal lesions are highly suggestive of VHLD.