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Objective To assess the application value of NCE-MRA using iMSDE prepared bSSFP sequence in lower limb in patients with diabetes. Methods This prospective study included a total of 35 patients with type II diabetes who underwent CE-MRA on the 1.5T MR scanner after the NCE-MRA. The obtained MIP images were independently rated by two radiologist with a four score table and using CE-MRA as a reference standard to evaluate the diagnostic accuracy of NCE-MRA for the narrowed arteries. The difference of the percent age of diagnostic arterial segments between NCE-MRA and CE-MRA on diabetic patients was evaluated by the χ2 test. Results Compared with CE-MRA, the diagnostic-value arterial segment ratio of pelvic arteries on NCE-MRA is decreased significantly. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of two readers in NCE-MRA were 95%/87%, 96%/95%, 57%/72%, 99%/99%, and 96%/95%(k=0.76), respectively. Conclusions The NCE-MRA using iMSDE prepared bSSFP sequence is capable of depicting vascu-lar lesions for the lower extremities in diabetic patients with the advantages of contrast agent free, short scan times and good diagnostic value in the thigh and calves.
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[Objective] Based on the resting state functional magnetic resonance imaging to investigate the abnormal features of the functional connectivity of resting brain neural network in the patients with primary insomnia,by using voxel-wise whole-brain finctional networks analysis of degree centrality (DC) for imaging evidence of neural mechanisms underlying primary insomnia.[Methods] The resting state fMRI were performed in 59 PI patients and 47 age,education,and sex-matched normal healthy subjects.Analysis of DC map changes between the two patient groups and the control group were performed by two sample t test.(threshold at P ＜ 0.05).[Results] Compared with the control group,the patients with PI showed significantly reduced DC value in bilateral medial frontal gyrus (MFG),bilateral anterior cingulate gyrus (ACG),and right insula;and increased DC value in right middle temporal gyrus (MTG),and left cuneus,(CUN),P ＜ 0.05.[Conclusion]Changes of DC value occurred in some region of brain in the P[patient groups when compared with the control group.It was indicated that DC,as a novel resting-state fMRI parameter in the voxel-wise whole-brain functional networks,might be an appealing alternative approach for further study on pathologic and neuropsychological states of PI.
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Objective To evaluate the effect of intravenous administration of gadolinium-DTPA on diffusion weighted imaging (DWI)of breast lesions and apparent diffusion coefficient(ADC)values,and to evaluate the diagnostic performance of post-contrast ADC for differentiating benign from malignant lesions in breast.Methods Thirty-eight histopathologically-confirmed breast lesions were analyzed.We examined the signal to noise ratio(SNR)of normal breast tissue and lesions and evaluated the contrast to noise ratio(CNR)of each lesion.We also assessed the relation between pre-and post-contrast ADC values.Results SNRs and CNRs of DWI before and after contrast were not significantly different.The mean post-contrast ADC values for malignant lesions significantly decreased after contrast injected (mean of -1 1.6%),while ADC values in the benign lesions were not significantly different before and after contrast.Conclusion Post-contrast ADC values may be a better indicator of potential breast tumors than pre-contrast ADC values.
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Objective To evaluate the valuations of the intracranial vertebrobasilar arteries using CT angiography (CTA) in order to improve the understanding of various variants in intracranial vertebrobasilar arteries.Methods The CTA images of 435 subjects were analyzed retrospectively.The data were collected by a 16-slice CT scanner.All the CTA images were processed technically by the maximum intensity projection and volume rendering.The intracranial vertebrobasilar arteries were measured and analyzed.Results Among the 435 subjects,bilateral intracranial vertebral arteries (V4) showed symmetry in 183 (42.07％) and dissymmetry in 252 (57.93％).Hypoplasia were found in 27 subjects (6.21％) on the left V4 segments and 36 (8.28％) on the right V4 segments,and a total of 21 (4.83％) were directly continued as the ipsilateral posterior inferior cerebellar arteries on the unilateral V4 segments.There were 2 subjects (0.46％) with vertebrobasilar dolichoectasia.There were 32 subjects (7.36％) had fenestration variation,3 of them (0.69％) were on the V4 segments,10 (2.30％) at the junctions,and 19 (4.37％) in the basilar arteries.Two subjects (0.46％) had persistent trigeminal arteries.Conclusions The variations of intracranial vertebrobasilar arteries mainly include angiodysplasia,vertebrobasilar dolichoectasia,fenestration variation,and persistent trigeminal artery.As a noninvasive vascular imaging method,CTA may accurately and visually assess the anatomic variation of intracranial vertebrobasilar artery,and provide imaging guidance for the preoperative evaluation of posterior fossa surgery.