ABSTRACT
Objective To study the CT and MRI characteristics of myxoid soft tissue tumours.Methods Fifty-three myxoid soft tissue tumours pathologically confirmed were retrospectively studied.MR and CT scan were performed before operation.Noncontrast T1 and T2 weighted images,fat-suppressed T2 weighted images were obtained before contrast-enhanced scan with fat-suppressed T1 weighted sequence was underwent.Plain and contrast-enhanced CT was performed with tube potential of 120 kV,matrix 512 × 512,and automatic tube current modulation technique.Results There were 18 myxoid liposarcoma,3 ganglioneuroma,8 myxofibrosarcoma,2 extraskeletal myxoid chondrosarcoma,10 intramuscular myxoma,and 2 juxta-articular myxoma.Microscopic examination showed myxoid soft tissue tumours which were consisted of abundant myxoid stroma with tumour cells and blood vessels associated with fibrous bands.Low density in CT images,hypointensity in T1 weighted images,significantly hyperintense in T2 weighted images were their common manifestations in the area of abundance of extracellular myxiod matrix.Plain CT images demonstrated equidensite,T1 weighted images isointensity,and fat-suppressed T1 weighted images significant enhancement relatively in the areas of increased number of tumor cells.Hemorrhage,necrosis and capsule of the lesion were revealed in high grade malignant tumors.The septa can be identified in most of myxoid tumours of soft tissue.Conclusion CT and MRI can definitely show the image characteristics of myxiod soft tissue tumours,which can help make a qualitative diagnosis before operation.
ABSTRACT
Aphasia is the loss or impairment of language caused by brain damage. Stroke is the most common cause of aphasia. The language function in most patients with aphasia will get recovery with different degrees no matter whether they have performed language training or not. In recent years, functional magnetic resonance imaging (fMRI) technology has been widely used in neuro-linguistic research, This article reviews the advances in research on investigating the recovery mechanisms of poststroke aphasia with fMRI.
ABSTRACT
Objective To observe the characteristic of the functional magnetic resonance imaging (fMRI) brain map in health adult undergoing clenching and relaxing the fist, for exploring the essence of the fMRI brain map in patients suffering from motor dysfunction by cerebrovascular accidents. Methods Twelve healthy volunteers had been chosen to partake the experience. Everyone had accomplished the following three actions separately: (1) Only clenching and relaxing the fist of left hand. (2) Only clenching and relaxing the fist of right hand. (3) Clenching and relaxing the fist of both hands at one time. The data had been analyzed statistically using analysis of functional neuroimages (AFNI) software. Results Under condition of F (6,1121), P = 0.005. Only clenching and relaxing the fist of left hand had gained the following brain functional area: right precentral gyms, left parietal,right superior temporal gyrus,right parietal, right parahippocampal gyrus, right superior frontal gyrus, right medial frontal gyrus, left precuneus, right superior parietal lobule, right middle frontal gyrus, left superior frontal gyrus. Only clenching and relaxing the fist of right hand had gained the following brain functional area: left precentral gyms, left postcentral gyrus right parietal, right medial frontal gyrus. Clenching and relaxing the fist of beth hands simultaneously had gained the following brain functional area: left precentral gyms,left postcentral gyrus, right precentral gyrus, right postcentral gyrus. Conclusions Hand movement (clenching and relaxing the fist) has its own specific brain activated areas. The brain areas activated by clenching and relaxing the fist of both hands simultaneously concentrate in the motor area of both cerebral hemisphere. The brain areas activated by clenching and relaxing the fist of single hand contain not only the motor area, but also the supplementary motor area. As compared with the right handedness, the brain areas activated by clenching and relaxing the fist of left hand is more widespread.
ABSTRACT
Objective To investigate the accuracy for absolute quantification of brain creatine (Cr) concentration using long time echo (TE) point resolved spectroscopy (PRESS) sequence performed with an external standard and postprocessed with the linear combination of model spectra (LCModel).Methods Ten swine (3.1±0.6 kg) and an external standard phantom containing detectable compounds of known concentration were investigated in this study by using 1.5 T GE Signa scanner and a standard head coil. The single-voxel proton magnetic resonance spectroscopy (1H-MRS) data were acquired from the two ROIs (2 cm×2 cm×2 cm) placed in swine brain and external standard solution using PRESS sequence with TE 135 ms,TR 1500 ms,and 128 scan averages.The in vivo quantification of Cr was accomplished by LCModel.After 1H-MRS examination,each animal was sacrificed immediately.In vitro Cr concentration was analyzed by high performance liquid chromatography (HPLC).Results In the 1H-MRS group,the Cr concentration was (9.37±0.14)mmol/kg.In the HPLC group,the Cr concentration was (8.91±0.13)mmol/kg.Good agreement was obtained between these two methods (t=9.038,P=0.491).Conclusion The long echo time PRESS sequence performed with an external standard and processed with LCModel iS proven to be an accurate technique to detect the in vivo brain Cr concentration.
ABSTRACT
Objective To investigate the relationship between multi-slice spiral CT perfusion imaging and tumor angiogenesis and cell cycle protein D1 (cyclinD1) expression in patients with peripheral lung cancer. Methods Seventy-three patients with peripheral lung cancer underwent 16-slice spiral CTperfusion imaging. The CT perfusion imaging were analyzed for time density curve (TDC), perfusion parametric maps and the respective perfusion parameters (BF, BV, PS, PH, and PHpm/PHa). Correlation between the respective perfusion parameters and immunohistochemical findings of MVD measurement and cyclinD1 expression were evaluated. Statistical method used one factor analysis of variance (One-wayANOVA) and Pearson correlation analysis. Results The shape of TDC of three groups of peripheral lung cancers (adenocarcinoma, squamous cell carcinoma, and other type of cancer) was similar. They showed a steeper slope, was obvious increase of nodular HU value [ peak height of TDC is respectively (44. 87±6. 83), (34. 91 ± 8.05), (40. 66±5. 87) HU ], changed little after reaching peak height, became flat at peak, had a platform. Forty-four patients were cyclinD1 positive expression, the peripheral lung cancers with cyclinD1 positive expression showed significantly higher MVD value than that of the peripheral lung cancers with cyclinD1 negative expression [ respectively (33.88± 14. 81), (23. 17±11.66) band/high magnification, P < 0. 01]. The cancers with cyclinD1 positive expression showed significantly higher PH,PHpm/PHa, BF,BV, PS value than those of the cancers with cyelinD1 negative expression[respectively P <0. 05]. MVD was positively correlated with PH, PHpm/PHa, BF, BV, and PS of the three groups ofcancers with cyclinD1 positive expression. Among, the correlation coefficient (r value) of BV, PS, BF was0. 409, 0. 517,0. 503 respectively(all P < 0. 01). MVD was significantly correlated with them. The r valueof PH, PHpm/PHa is 0. 319,0. 324 respectively(all P < 0. 05). MVD was less correlated with them. MVDwas not correlated with PH, PHpm/PHa, BF, BV, and PS of the three groups of cancers with cyclinD1 negative expression. Conclusions Multi-slice spiral CT perfusion imaging moderately correlated with tumorangiogenesis and reflected MVD measurement and cyclinD1 expression. It provided not only a noninvasive method of quantitative assessment for blood flow patterns of peripheral lung cancer but also an applicable diagnostic method for peripheral lung cancer.