Factors associated with cerebral microbleeds in patients with ischemic stroke / 中华神经医学杂志

Objective To investigate the clinical and neuroimaging features of cerebral microbleeds(CMBs)in patients with ischemic stroke. Methods MRI,including gradient-echo T2~*-weighted MRI,was performed in 85 patients with acute ischemic stroke.Their clinical information and imaging characteristics were analyzed. Results One hundred and twenty-four CMBs were noted in 26 patients(30.6%)with the number of CMBs ranged from 1 to 16 per patient.CMBs were more frequently presentcd in the cortical-subcortical region and thalamus-basal ganglia than in the cerebellum and brain stem legions.Some CMBs in the brain stem had related neurological symptoms and signs.CMBs,the age of the patient,the number of lacunar infarcts and the white matter changes were correlative(r=0.243,P=0.025;r=0.337,P=0.025;r=0.438,P=0.000).CMBs could be well demonstrated in the gradient-echo T2~*-weighted MRI and some larger ones could be demonstrated in the apin-echo T2~*-weighted MRI and DWI. Conclusion CMBs are the sighs for microangiopathy in the brain with advanced age,mutiple lacunar infartion and leukoaraiosis as its main prognosis factors.

The Comparison between Single Shot Turbo Spin Echo and B-FFE (Balanced Turbo Field-echo) in the Differentiation of Focal Liver Lesions

PURPOSE: To determine the diagnostic accuracy of four different sequences : moderately T2 weighted, two heavily T2-weighted single shot turbo spin-echo sequence and breath-hold axial-2D balanced turbo field-echo sequence(bFFE) for characterization of focal lesions. MATERIALS AND METHODS: During the 3-month period between June and August 2005, seventy-six patients were proved to have ninety-three focal hepatic lesions on MR imaging. The patients consisted of 49 men and 27 women (age range, 15-75 years; mean age, 56.23 years). All MR images were acquired on a 1.5-T MR using the following sequences: 1. A breath-hold axial T2-weighted single shot turbo spin-echo sequence, 2. a breath-hold axial-2D balanced turbo field-echo sequence. Two radiologists performed quantitative analysis. Another radiologist measured the lesion-to-liver contrast-to-noise ratio at the region-of-interest in the four sequences. RESULTS: There was no significant difference in inter-observer variability between the four sequences. The accuracy for both cyst and malignancy of moderate T2 weighted MRI (echo time: 80 msec) was also highest. There was significant difference for lesion characterization between moderate T2 weighted MRI and balanced steady state procession (p-value: 0.004) in the second reader. For longer echo time, the CNR of cystic lesions were markedly increased in comparison to lesions of other component. CONCLUSION: The accuracy and inter-observer variability of single shot turbo spin echo T2 weighted sequence was higher than bFFE. Although there was no statically significant difference, moderate T2 weighted MRI (echo time: 80 msec) was more accurate than heavily T2 weighted sequence (echo time: 300 msec). If the results for lesion characterization is equivocal in TE 80, the addition of heavily T2 weighted MRI (echo time: 180 msec) can be helpful.

A research for the relative signal intensity of the retrodiscal tissue in the temporomandibular joint disorder patients on MRI

The relative signal intensity of retrodiscal tissue in TMJ using a T2-weighted MRI