Analysis Of Arterial Spin Labeling In Hypoxic Ischemic Encephalopathy

ObjectivesImage of Magnetic resonance spectroscopy (MRS) has become the diagnostic criteria of Hypoxic ischemic encephalopathy (HIE) in neonates. In addition, to discuss the diagnostic value of arterial spin labeling (ASL) technology in newborns with HIE.MethodsSeven full-term newborn infants with no history of asphyxia and no other nervous system diseases were selected as the control. And 33 full-term newborn infants with hypoxic ischemic encephalopathy (HIE) were divided into three groups (19 cases in mild group,6 cases in moderate group and 8 cases in severe group) based on their clinical diagnosis. Both control group and HIE groups were examined with GE Signa EXCITE HD 3.0T superconducting MRI scanner with quadrature head coil. And both groups were scanned using conventional axial MRI (T1WI, T2WI, FLAIR), 1HMRS (using PRESS sequence) and ASL (FAIR). Original images of 1HMRS and ASL were processed by Functool software of ADW 4.3 workstation. The metabolites of NAA,Cho,Cr and Lac on the bilateral basal ganglia, thalamus and frontal white matter, were measured with 1HMRS, and the peak height ratio were calculated and observed. ASL perfusion images were examined, and the signal intensity values of region of interest (bilateral gray and white matter, basal ganglia) of the two groups were quantitatively measured, and mean value were calculated and compared between groups. Statistical analysis was obtained with SPSS 12.0 software, and statistically significant difference is P<0.05.Results1HMRS can be an early of hypoxic-ischemic brain lesions, HIE group compared with the control group,, Lac/Cr was obviously high that is statistical significance(P<0.05), NAA/Cr and NAA/Cho was low that is statistical significance (P<0.05), Cho/Cr compared with the control group, no significant difference (P>0.05).The perfusion images of two groups were obtained perfectly. The signal intensity value of bilateral gray and white matter, basal ganglia of control group were 125.34±11.76,73.42±11.67,173.65±15.49, respectively, and there is a statistically significant difference between the different areas. The signal intensity value of bilateral gray and white matter, basal ganglia of HIE group were 153.47±11.72,71.35±10.37,207.13±12.51, respectively. There was a statistically significant difference (P<0.05) of the average signal intensity value of gray matter and basal ganglia and no statistically significant difference (P>0.05) of white matter between two groups.Conclusions1. 1HMRS can be an early sensitive indicator of hypoxic-ischemic brain lesions, and ASL MR Perfusion provides metabolic control analysis of material information.2. For HIE comfirmed with the 1HMRS, ASL MR Perfusion technique without any contrast agent can_detect the disease effectively and reliably Therefore, it is an ideal functional MR examination for brain perfusion in the newborn with HIE.3. Combined with conventional MRI,1HMRS and ASL MR Perfusion technique can assessed HIE comprehensively and accurately, furthermore, it can evaluated the brain damage of hypoxic ischemic. The results provide a strong basis for clinical treatment.