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Objective To investigate the value of 3D pseudo-continuous arterial spin labeling (3D-pCASL) magnetic resonance perfusion technique in evaluating posterior circulation ischemia (PCI) of the elderly beyond 80 years old and to offer the evidence of PCI of the elderly for clinical diagnosis. Methods Totally 53 male subjects older than 80 years were recruited in this study,including 20 subjects with clinically diagnosed PCI and 33 normal subjects. All the subjects underwent routine brain magnetic resonance imaging and 3D-pCASL sequence on a 3.0T magnetic resonance imaging system with 8 channel brain coil. Two post-labeling delay (PLD) time (PLD=1525 ms and PLD=2525 ms) of 3D-pCASL were used in this study to increase the accuracy of cerebral blood flow (CBF) change of posterior circulation region. We used SPM12 software to measure mean CBF values of bilateral occipital lobes and bilateral cerebellums. Independent sample t-test and rank-sum test were performed to evaluate the difference of CBF changes of anterior circulation and posterior circulation in two groups at two PLD time,the difference of CBF changes of bilateral occipital lobes and bilateral cerebellums in two groups of two PLD time,and the difference of increment of CBF between two PLD interval between two groups. Results In case group,the CBF value of the anterior circulation was significantly higher than that of posterior circulation at both two PLD time points (PLD=1525 ms and PLD=2525 ms)(P=0.000,P=0.000);in control group,the CBF value of the anterior circulation was significantly higher than that of the posterior circulation only at PLD=1525ms (P=0.025). The CBF values at bilateral occipital lobes and bilateral cerebellums at two PLD time points (PLD=1525 ms and PLD=2525 ms) were significantly higher in case group than in control group(P=0.003,P=0.002,P=0.000,P=0.001,P=0.000,P=0.001,P=0.002,P=0.014,respectively). Compared with the control group,the difference was statistically significant in bilateral occipital lobes and cerebellums with a smaller △CBF between two PLD interval in case group (P=0.004,P=0.001,P=0.001,P=0.025). Conclusion Multiple PLD time points need to be used in 3D-pCASL in diagnosing PCI of the elderly because the posterior circulation is slow in these patients. 3D-pCASL technique is sensitive in detecting decreased CBF in posterior circulation and therefore can be used to predict posterior circulation stroke in the elderly.
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<p><b>OBJECTIVE</b>To evaluate the diagnostic efficacy of IFIR-FIESTA technique in detecting renal artery stenosis in elderly patients.</p><p><b>METHODS</b>Twenty-seven aged patients underwent both IFIR-FIESTA and 3D CE-MRA examinations. The imaging quality and renal artery stenosis grades were evaluated. Kappa test was used to assess the consistency between the two methods. With CE-MRA as the reference, the diagnostic sensitivity, specificity, accuracy, PPV and NPV for IFIR-FIESTA were calculated in detecting renal artery stenosis.</p><p><b>RESULTS</b>The images by the two methods were 100% qualified for diagnosis, although the image quality of CE-MRA was significantly better. IFIR-FIESTA and CE-MRA showed excellent consistency in detecting renal artery stenosis. With CE-MRA as the reference, the diagnostic sensitivity, specificity, accuracy, PPV and NPV for IFIR-FIESTA were 97.1%, 100%, 98.1%, 100%, and 95% in detecting renal artery stenosis, respectively.</p><p><b>CONCLUSION</b>IFIR-FIESTA is feasible as a routine examination for detecting renal artery stenosis in elderly patients.</p>
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Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Contrast Media , Feasibility Studies , Magnetic Resonance Angiography , Methods , Renal Artery Obstruction , Diagnosis , Sensitivity and SpecificityABSTRACT
Purpose To explore the correlation between whole body magnetic resonance diffusion-weighted imaging (WB-DWI) quantitative parameters of healthy adults' bone marrow with gender, age, height, weight, body mass index, and sex hormone levels. Materials and Methods 108 healthy adult subjects in different age groups underwent WB-DWI scan using GE 1.5T MR scanner, among them estradiol and progesterone levels were measured in 60 subjects within 48 hours before or after the scan. Apparent diffusion coefficient (ADC) values of bone marrow and the signal to noise ratio (SNR) were compared among different gender and age groups. Partial correlation analysis was used to evaluate the correlation of skeletal system ADC values and SNR with sex, age, height, weight, body mass index, estradiol and progesterone levels in 60 subjects. Results ADC values and SNR of the female subjects were significantly higher than males (P<0.01);there were significantly differences for skeletal system ADC values and SNR in different age groups (P<0.01). Skeletal system ADC values was significantly negatively correlated (r=-0.642, P<0.01) with age, and were mildly positively correlated (r=0.278, 0.271, P<0.05) with estradiol and progesterone levels;SNR was significantly negatively correlated (r=-0.709, P<0.01) with age, and was mildly positively correlated (r=0.293, P<0.05) with estradiol levels;ADC values and SNR had no significant correlation with height, weight and body mass index. Conclusion Skeletal system ADC values are effected by gender, age and sex hormone levels, the skeletal system WB-DWI manifestations are different in different gender and age groups.
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Objective To investigate the techniques of lower limbs MRI. Methods 50 patients underwent lower limbs MRI examinations on 1.5T scanner using 4-channel torso coil, in which 28 were femur and 22 were tibia and fibula. Pulse sequences included FSE T2WI and SE T1WI. All FSET2WI were added with fat saturation. FOV is 42cm?42cm. Imaging planes included axial, coronal and saggital views. Slice thickness ranged from 8mm to10mm on axial and 4mm to 5mm on sagital or coronal view. Results Axial view could delineated the anatomical relationship of the lesions. Coronal or sagital view could show the global view and relation to the adjacent structure. Conclusion The proper scan skill, optimized parameters and proper pulse sequences are essential for better delineation of the anatomy of the lower extremities and helpful for the location and the diagnosis.
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Objective To explore MRI of sacroiliac joint.Methods MRI was applied to 33 patients on transaxial FSE T2WI and SE T1 WI,coronal FSE T2 WI and two coronal FSPGR.Results Sacroiliac joints of 7 patients were normal,and all the sequences could directly show the cartilage of normal sacroiliac joints.The other 26 patients suffered from ankylosing spondylitis(AS),and cartilage abnormality appeared in 42 sacroiliac joints from 52 joints.The irregular thickened or tortuous ones replaced the linear intermediate signals on T1WI and T2WI.Conclusion Such measures do good to MRI of normal sacroiliac joint structure and pathological changes as optimization of scanning parameters,selection of proper scanning method and coil,as well as application of T2WI and FSPGR in phase fat suppression technology.
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AIM:The ultrastructure,the levels of NO - 2/NO - 3 were investigated in the myocardium of rats with non-insulin dependent diabetes mellitus. METHODS: In order to establish a model of non-insulin dependent diabetes mellitus (NIDDM), we injected rats with small dose streptozocoi (iv). Two weeks after the injection, the rats developed impaired glucose tolerance. Then, they were fed with high energy diet for eight weeks to form NIDDM. RESULTS: (1) The ultrastructures of cardiac myocytes of NIDDM rats were changed evidently, with swelled mitochondrion and widened intercalated-disk gap; (2) The levels of NO - 2/NO - 3 in the heart tissue of NIDDM rats were significantly lower than those of normal rats( P