ABSTRACT
Twelve healthy volunteers underwent ECG-triggered non-contrast-enhanced magnetic resonance venography(NCE-MRV)of lower extremities on a 1.5T MR scanner.Image quality was assessed quantitatively and qualitatively with a 17-segment model.ECG-triggered (NCE-MRV) was successfully performed in all patients.Mean signal to noise ratio and contrast to noise ratio of lower extremities were 66 ± 23 and 53 ± 22 respectively.Excellent and good image qualities were achieved in 62％ and 31％ of all segments respectively without non-evaluable segment.Thus ECG-triggered NCE-MRV of lower extremities is feasible with reliable image quality.
ABSTRACT
Objective To investigate the value of susceptibility weighted imaging (SWI) in the diagnosis of hemorrhagic diffuse axonal injury (DAI). Methods A retrospective study was conducted on 20 patients with DAI who received MRI examination at day 3 post-injury.MRI sequences included T1WI,T2WI,fluid attenuated inversion recovery ( FLAIR),diffusion weighted imaging (DWI) and SWI.There were 15 patients with the Glasgow Coma Scale (GCS) score≤8,three with GCS score of 9-12 and two with GCS of 13-15.The location and quantity of hemorrhage focus were counted.The area of hemorrhage focus was measured on each MR sequence.Differences of detection rate of hemorrhage focus on each sequence were compared by using X2 test.The correlation between DAI related bleeding area and GCS score was analyzed. Results DAI related hemorrhage focus showed a larger number in superficial cerebrum than that in posterior cranial fossa and in deep cerebrum.The detection rate of hemorrhage focus on SWI was the highest,as compared with other sequences ( P ＜ 0.05 ).Bleeding area and GCS score showed a negative correlation (r =-0.921,P ＜ 0.01 ). Conclusion SWI is very sensitive in detection of the intracerebral hemorrhage focus in the acute period of traumatic DAI.