Clinical application of turbo gradient and spin echo-BLADE diffusion weighted imaging at the sellar region / 中华放射学杂志

Objective:To compare the image quality of turbo gradient and spin echo-BLADE diffusion weighted imaging (TGSE-BLADE-DWI) with that of readout segmentation of long variable echo-trains (RESOLVE) at the sellar region.Methods:From September 15 th, 2019 to February 15 th, 2020, 38 patients with suspected sellar abnormalities were enrolled prospectively to perform RESOLVE and TGSE-BLADE-DWI at a 3.0 T MR scanner in Department of Radiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology. Totally, 32 patients were identified with sellar lesions. The DWI images were evaluated subjectively and objectively. Two experienced radiologists scored images of the two DWI methods for anatomical structures (including the internal carotid arteries, optic chiasm, pituitary stalk and pituitary gland), lesion conspicuity, susceptibility artifacts, geometric distortions and overall image quality using a five-point scale respectively. Objective parameters on the images of the two DWI methods were analyzed, including lesion size, signal to noise ratio (SNR) and apparent diffusion coefficient (ADC). The consistency of subjective scores of two radiologists was tested by Kappa test. Paired t-test, Wilcoxon signed rank test, Kappa statistics were used for statistical evaluation. Results:TGSE-BLADE-DWI performed significantly better than RESOLVE in depicting the sellar anatomical structures, lesion conspicuity, geometric distortion and overall image quality (all P<0.05). There were no significant differences in SNR, maximum longitudinal diameter of lesions and ADC of lesions between the two DWI methods(all P>0.05). The maximum transverse diameter measured by TGSE-BLADE-DWI was significantly smaller than that of RESOLVE ( Z=3.31, P=0.001). Conclusions:Compared with RESOLVE, TGSE-BLADE-DWI is superior in depicting the anatomical structures, decreasing susceptibility artifacts and geometric distortions at the sellar region and effectively improves the image quality of DWI, which has great value in clinical applications.

Comparisons of the specific absorption rate in 3.0T MR brain examination / 实用放射学杂志

Objective To investigate the specific absorption rate (SAR)in 3.0T MR brain examination.Methods All 280 patients underwent 3 .0 MR brain examination.And the patients were divided into three groups:a group of 0-3 years old without hands intersection, inluding 40 cases through conventional MRI examination,40 cases through MRA,as well as 40 cases through DWI;a group of more than 20 years old without hands intersection,including 40 cases through conventional MRI examination,40 cases through MRA,as well as 40 cases through DWI;a group of more than 20 years old with hands intersection,consisting of 40 cases through MRA.The SAR values of each group were recorded,respectively.And the independent samples t test was used to compare statistical difference of different SAR values between groups.Results Compared the group of 0-3 years old without hands intersection and the group of more than 20 years old without hands intersection,the SAR values of all six sequences in front group were significantly higher than that those in latter one,but not exceed the safety standard of 3 w/kg in the United States FDA.There was no significant statistical differences in the SAR values of two groups which more than 20 years old with hands intersection or not (P>0.05).Conclusion The SAR values of each sequence in the group of 0-3 years old without hands intersection were significantly higher than those in the group of more than 20 years old without hands intersection,but in a safe and reasonable range.The brain scanning with two hands intersect of 20 years old and above,and there was no significant increase on the SAR values in the brain examination of the group of more than 20 years old with hands intersection.So it is of great significance to guide the daily work,settle doubts and improve success rates of the MR examination.

Comparisons of the specific absorption rate in 3.0T MR brain examination / 实用放射学杂志

Objective To investigate the specific absorption rate (SAR)in 3.0T MR brain examination.Methods All 280 patients underwent 3 .0 MR brain examination.And the patients were divided into three groups:a group of 0-3 years old without hands intersection, inluding 40 cases through conventional MRI examination,40 cases through MRA,as well as 40 cases through DWI;a group of more than 20 years old without hands intersection,including 40 cases through conventional MRI examination,40 cases through MRA,as well as 40 cases through DWI;a group of more than 20 years old with hands intersection,consisting of 40 cases through MRA.The SAR values of each group were recorded,respectively.And the independent samples t test was used to compare statistical difference of different SAR values between groups.Results Compared the group of 0-3 years old without hands intersection and the group of more than 20 years old without hands intersection,the SAR values of all six sequences in front group were significantly higher than that those in latter one,but not exceed the safety standard of 3 w/kg in the United States FDA.There was no significant statistical differences in the SAR values of two groups which more than 20 years old with hands intersection or not (P>0.05).Conclusion The SAR values of each sequence in the group of 0-3 years old without hands intersection were significantly higher than those in the group of more than 20 years old without hands intersection,but in a safe and reasonable range.The brain scanning with two hands intersect of 20 years old and above,and there was no significant increase on the SAR values in the brain examination of the group of more than 20 years old with hands intersection.So it is of great significance to guide the daily work,settle doubts and improve success rates of the MR examination.

Comparison of renal artery in-flow inversion recovery MR angiography versus CT angiography or contrast-enhanced MR angiography / 中华放射学杂志

Objective To compare the image quality of renal artery in-flow inversion recovery MR angiography (IFIR MRA), CTA and contrast-enhanced MR angiography (CE-MRA) and to assess the value of renal artery IFIR MRA. Methods Thirty five patients were prospectively included in this study.Renal artery CTA was performed in 19 patients and renal artery CE-MRA was performed in 16 patients. In addition to renal artery CTA or CE-MRA, all patients underwent renal artery IFIR MRA. Two radiologists separately graded renal artery image quality, renal venous artifact and the visualization of renal artery branches regarding these three different techniques. Wilcoxon signed rank test of paired samples was used to compare the grading results, t test of paired samples was applied to compare the results of renal artery (accessory renal artery) trunk diameter. The consistency evaluation of renal artery image quality and renal venous artifact grades between two radiologists employed Kappa analysis. Results There was no significant difference between IFIR MRA and CTA with renal artery image quality and renal venous artifact (P>0.05). There was significant difference between IFIR MRA and CE-MRA with renal artery image quality and renal venous artifact (P0.05).CE-MRA of 16 cases depicted 38 renal arteries (32 renal arteries, 6 accessory renal arteries), IFIR MRA depicted them all. The grades of visualization of renal artery branches about IFIR MRA and CE-MRA were (3.4±0.8) and (2.5±0.9) respectively, and there was significant difference between IFIR MRA and CE-MRA (Z=-4.040, P0.05). Conclusions The image quality of renal artery IFIR MRA was equal to CTA and superior to CE-MRA. It could be considered as an alternative technique for renal artery angiography.

Noninvasive diagnosis of cardiac amyloidosis by MRI and echochardiography / 华中科技大学学报（医学）（英德文版）

This study described the radiological features on echocardiography and MRI specific to cardiac amyloidosis confirmed on biopsy. Eleven cases of biopsy-proven cardiac amyloidosis were retrospectively reviewed in this study. All patients underwent biopsy, cardiac MRI and echocardiography. The main echocardiography and MRI findings were as follows: diffuse ventricular and septum wall thickening, atrial enlargement, pericardial effusion, restricted left ventricular (LV) systolic and diastolic function, characteristic granular sparkling of myocardium. MRI revealed a characteristic pattern of global subendocardial late enhancement, extending in varying degrees into the neighboring myocardium. The findings agreed with the infiltration distribution of amyloid protein. Typical abnormalities seen on echocardiography and MRI should have important diagnostic and prognostic value of cardiac amyloidosis. MRI should be considered in the diagnosis of cardiac amyloidosis if echocardiographic features are suspicious.

MRI and echocardiography in the diagnosis of cardiac amyloidosis / 中华放射学杂志

Objective To assess the values of MRI and echocardiography for the diagnosis of cardiac amyloidosis (CA). Methods Eleven cases with CA proved pathologically performed MRI and echocardiography, the findings were analyzed retrospectively. Results The characteristic features of cardiac amyloidosis on MRI and echocardiography were:diffuse slight myocardial thickening of the left ventricular wall and interventricular septum (11 cases ), slight myocardial thickening of the interatrial septum (5 cases), increased left ventricular mass (7 cases), enlarged left atrium ( 7 cases), impaired ventricular systolic and diastolic function (10 cases ), pleural and pericardial effusions (11 and 9 cases ).Echocardiography showed that myocardium was hyperechoic and presented as ground glass with some spotty hyperechoes in 6 cases. MRI revealed a distinct diffuse delayed enhancement of subendocardial and entire myocardium in 8 cases. Conclusion Doppler echocardiography is the first-choice imaging technique and cardiac magnetic resonance imaging can provide more information for the diagnosis of CA.

MRI and pathologic correlation of cardiac myxomas / 中华放射学杂志

Objective To investigate the MRI features of cardiac myxoma by correlated with its pathological findings. Methods MRI features of 22 cases of pathologically confirmed cardiac myxomas were retrospectively reviewed. Results Of 22 cases, 21 are solitary, 12 located in left atrium, 6 located in right atrium, 2 located in left ventricle and 1 located in right ventricle. The other one occupied multiple chambers. MRI: 19 are heterogeneous and 3 are homogeneous. Cine-MRI: 18 attach to the endocardium with a pedunculated stalk and 4 are sessile and with a broad attachment. Thirteen cases had secondary valve insufficience or stenosis. Nine have compromised cardiac function. Nineteen cases demonstrated mild to moderate heterogeneous enhancement after Gd-DTPA administration and 3 ease showed no enhancement. Four cases had gadolinium first-pass perfusion study and showed a slow and continuous increasing time-intensity, lower than normal myocardium. The pedicles and wall showed delay enhancement. Pathologic findings: 21 are oval and lobalar configuration, 1 is grape-like. Ten cases had fresh hemorrhage and 5 had chronic hemorrhage. Fourteen had necrosis , 2 had cystic change and 4 had calcification. Blood vessels or inflanmmtory cells could be detected in 19 cases. Conclusions MRI can evaluate the size, location, morphology, especially the vascularity, histologic features and cardiac function of cardiac myxomas.

Electroacupuncturing acupoints of patients with peripheral facial paralysis: a functional MRI study / 中国医学影像技术

Objective To explore the brain changes of electroacupuncturing (EA) different acupoints of peripheral facial paralysis (PFP) with functional magnetic resonance imaging (fMRI). Methods Eighteen patients with left PFP were randomly divided into three groups. Six of them received electroacupuncturing left Dicang, 6 received electroacupuncturing left Hegu, and 6 received electroacupuncturing left Houxi. fMRI data were obtained from scanning of the whole brain. Functional data were processed by SPM99 software and functional responses were established with t-test analysis (P<0.05). Results Electroacupuncturing Dicang and Hegu on the left induced decreasing of signal in bilateral middle frontal gyrus, left cingulate gyrus, signal increased of right precentral gyrus, bilateral postcentral gyrus, left superior temporal gyrus and right insular, while electroacupuncturing Houxi on the left induced decrease of signal in bilateral inferior frontal gyrus, left lentiform nucleus, right middle temporal gyrus, right cerebellar tonsil, signal increased of right caudate head, right cingulate gyrus, brainstem, cerebellar vermis and right parahippocampal gyrus. Conclusion Electroacupunctuing Hegu and Dicang can cause corresponding functional activation in cerebrum, while electroacupuncturing Houxi can not, suggesting that there is association between cerebral and acupoint of owned meridian.

Diffusion-weighted single-shot echo planar MR imaging of normal human prostate using different b values / 华中科技大学学报（医学）（英德文版）

This study examined the effect of different b values on diffusion-weighted MR imaging (DWI) of human prostate by using single-shot spin echo echo planar imaging (SE-EPI) sequences, observed the normal appearances and measured apparent diffusion coefficient (ADC) values in anatomical regions of normal prostate. Twenty-four healthy volunteers (mean age: 32 y) were studied by using a 1.5T system with a phased array surface multicoil. Two kinds of single-shot SE-EPI sequence were used to perform DWI in the prostate in volunteers, with five b values being 0, 30, 300, 500 to 1000 s/mm(2). The image quality with different imaging parameters was analyzed and the ADC values in anatomical regions of normal prostate were measured. DWI of prostate was successfully obtained in all volunteers. The images were of good quality, without artifacts containing pixels within the prostate. The contrast was good between the different anatomical regions of the prostatic gland, i.e., the peripheral zone (PZ), which exhibited higher signal intensity, and the central gland (CG). Signal intensity contrast was related to the magnitude of b values. The ADC values in PZ and CG were (1.27+/-0.22)x10(-3) mm(2)/s and (1.01+/-0.17)x10(-3) mm(2)/s, respectively. The ADC values were found to be significantly higher in PZ than in CG (P<0.05, paired t-test). Significant differences were found between the slice-selecting component and both the read-out and phase-encoding components of the ADC values. It is concluded that SE-EPI is a suitable DWI sequence for human prostate. The contrast between PZ and CG is good when b values are low, while the diffusion and ADC values are accurate when b values are high. ADC values are higher in PZ than in CG in normal prostate. Diffusional anisotropy is present in normal prostatic tissue.

MRI features of intracranial primitive neuroectodermal tumors in adults: comparing with histopathological findings / 华中科技大学学报（医学）（英德文版）

The MRI appearances of 7 adult patients with pathologically proven intracranial primitive neuroectodermal tumors (PNET) were retrospectively analyzed. The MRI features were compared with findings in pathology and surgery. In this group, the tumor masses were most commonly found in the semisphere of cerebrum and in the vermis of cerebellum. They were relatively large and 4 were in lobulated shape. All of them had well-defined margins. MR images showed the tumors to be mildly or obviously hypointense on T1-weighted images and hyperintense on T2-weighted images. Most masses had heterogeneous appearances with some cystic and necrotic areas. Intratumoral haemorrhage and focal calcification were occasionally seen. Mostly, there was no or only mild surrounding edema. Marked inhomogeneous contrast enhancement on MRI was seen in 6 cases except one. Two patients with multiple intracranial metastases were revealed on MR images. In this series, there was good correlation between MRI features and findings in pathology and surgery. These results showed that certain MRI features might suggest the diagnosis of intracranial PNET in adults. MRI is an effective technique to detect these tumors and is helpful to treatment planning and follow-up.

MRI features of intracranial primitive neuroectodermal tumors in adults: comparing with histopathological findings / 华中科技大学学报（医学）（英德文版）

The MRI appearances of 7 adult patients with pathologically proven intracranial primitive neuroectodermal tumors (PNET) were retrospectively analyzed. The MRI features were compared with findings in pathology and surgery. In this group, the tumor masses were most commonly found in the semisphere of cerebrum and in the vermis of cerebellum. They were relatively large and 4 were in lobulated shape. All of them had well-defined margins. MR images showed the tumors to be mildly or obviously hypointense on T1-weighted images and hyperintense on T2-weighted images. Most masses had heterogeneous appearances with some cystic and necrotic areas. Intratumoral haemorrhage and focal calcification were occasionally seen. Mostly, there was no or only mild surrounding edema. Marked inhomogeneous contrast enhancement on MRI was seen in 6 cases except one. Two patients with multiple intracranial metastases were revealed on MR images. In this series, there was good correlation between MRI features and findings in pathology and surgery. These results showed that certain MRI features might suggest the diagnosis of intracranial PNET in adults. MRI is an effective technique to detect these tumors and is helpful to treatment planning and follow-up.

Differential diagnosis of arachnoid cyst from subarachnoid space enlargement by phase-contrast cine MRI / 中华医学杂志(英文版)

<p><b>OBJECTIVES</b>To reveal the relationship of brain motion and cerebrospinal fluid (CSF) flow by phase-contrast cine MRI, and to evaluate this technique in differentiating between arachnoid cysts and subarachnoid space enlargement.</p><p><b>METHODS</b>Using a phase-contrast cine MRI pulse sequence, we measured brain motion and CSF flow during the cardiac cycle in 10 healthy volunteers and 10 patients with MRI-suspected arachnoid cyst or subarachnoid space enlargement. CSF stroke volume curve was illustrated according to flow quantification, and time-signal intensity curve was traced. The two curves were compared.</p><p><b>RESULTS</b>This study showed that brain motion was due to the volume difference between arterial and venous blood flow during a cardiac cycle, and thus drives CSF pulsation. Arachnoid cysts and subarachnoid space enlargement carried different curve patterns, demonstrating that phase-contrast MRI and flow quantification can be a useful and reliable technique for non-invasive evaluation of brain motion and CSF flow.</p><p><b>CONCLUSION</b>Arachnoid cysts can be successfully differentiated using phase-contrast cine MRI from subarachnoid space enlargement.</p>