›› 2012, Vol. 32 ›› Issue (11): 1476-.doi: 10.3969/j.issn.1674-8115.2012.11.017

• Original article (Basic research) • Previous Articles     Next Articles

Experimental study of 3.0T diffusion weighted imaging and diffusion tensor imaging in diagnosis and outcome prediction of cerebral blast injury

WU Peng1, LÜ|Guo-shi2, HAN Feng2, XU Ke-ning2, WANG Hai-chen2   

  1. 1.School of Graduate Studies, Hebei North University, Zhangjiakou 075000, China;2.Department of Radiology, 251 Hospital of PLA, Zhangjiakou 075000, China
  • Online:2012-11-28 Published:2012-11-30

Abstract:

Objective To investigate the value of diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) in diagnosis of non-hemorrhagic foci and white matter fiber injury early after blast in rabbits, and explore their role in outcome prediction. Methods Thirty New Zealand rabbits were selected, and model of cerebral blast injury was established. After injury, routine CT, magnetic resonance imaging (MRI), DWI and DTI were performed, and quantified analysis of region of interest was conducted with Functool 2 postprocessing technology. The cerebral histopathological changes were observed, and contrast analysis was carried out with findings from DWI and DTI of the same plane. Results Of the 30 rabbits, there was no abnormal cerebral imaging findings in 6 rabbits by CT, T1WI and T2WI, and there was no abnormal low signal in 2 of the 6 rabbits by DWI. Among the other 24 rabbits, CT only revealed pneumatosis in brain, MRI routine subsequence demonstrated non-hemorrhagic foci, which were characterised by low or slightly lower signal on T1WI and high signal on T2WI, and DWI indicated bright-white high signal. DWI illustrated 189 non-hemorrhagic foci, which exhibited punctiform (28.5%), lamellar (54.0%) and slinar (17.5%) high signal, with sharp border. The number of non-hemorrhagic foci detected by DWI was significantly larger than those revealed by conventional T1WI and T2WI (P<0.01). DTI demonstrated decrease in apparent diffusion coefficient (ADC) and fiber tractography (FA) of region of interest, especially for the inner capsule (P<0.01). There was linear correlation of decrease in ADC and FA values of cerebral white matter and brain stem with time of survival of rabbits (r=0.53,P=0.05;r=0.13,P=0.03;r=0.25,P=0.04;r=0.27,P=0.02). Conclusion DWI may provide higher detection rate for non-hemorrhagic foci in rabbits with cerebral blast injury, especially for small lamellar non-hemorrhagic foci. DTI may play a role in outcome prediction through measurement of decrease in ADC and FA values.

Key words: blast injury, diffusion weighted imaging, diffusion tensor imaging, magnetic resonance imaging