Research Of DWI Combined With Conventional MRI On HIE Of Full-term Neonates And White Matter Damage Of Prematures

Part Ⅰ DWI combined with conventional MRI in diagnosis of HIEof full-term neonatesObjective To explore the value of DWI combined with conventional MRI in diagnosisof hypoxic ischemic encephalopathy(HIE) of full-term neonates with different ages.Methods Totally220full-term neonates of diagnosed as HIE (case group)wereanalyzed retrospectively, of which119neonates aged <7days（case group1）, and101neonates aged7-28days（case group2）, which26and17normal newborns with the sameages were selectedn as control group1(n=26)and control2(n=17),retrospectively. All thenewborns underwent conventional MRI and DWI examination，and ADC values of8ROIs inbrain were measured， and the correlation between ADC of all ROIs and clinicaldegree,neonatal behavioral nurological assessment were analyzed.Results ADC values of ROIs of all newborns were higher in peripheral white matterthan that in central white matter, which the highest ADC values in the deep frontal whitematter and parietal white matter, and the lowest ADC values in the posterior limb of theinternal capsule (PLIC). ADC values of frontal white matter, parietal white matter,periventricular white matter and the ventral lateral nucleus of thalamus in control group2were significantly lower than that in control1（t=5.87,4.30,2.62,3.10, all P <0.05）. ADCvalues of frontal white matter,parietal white matter, the splenium of the corpus callosum andthe PLIC with moderate HIE in case group1were significantly lower than those in controlgroup1（P<0.05）, for severe HIE ADC values of periventricular white matter and the ventral lateral nucleus of thalamus were also significantly lower than those in control group1（P<0.05）；For case group2, ADC values of the PLIC and splenium of corpus callosum inmoderate and severe HIE group were significantly lower than those control group2（P<0.05）.NBNA scores decreased with mild, moderate, severe brain injury and all NBNA scores werelower than the match control group，there was significant difference between groups in case1and2(P<0.05).There was negative correlation between ADC values of the frontal and parietalwhite matter, periventricular white matter, PLIC, the spienium of corpus callosum，thalamusand HIE clinical degree, and positive correlation between ADC values of the frontal andparietal white matter, periventricular white matter, PLIC, the spieniumof corpus callosum,thalamus and NBNA scores, among all correlations, between ADC values of PLIC andNBNA score, HIE clinical degree is best correlaition in case group1（P<0.05）; There wascorrelation between ADC values of the PLIC and the spieniumof corpus callosum and clinical,NBNA scores in case group2（P<0.05）.Conclusion DWI possesses the advantages compared with conventional MRI to findHIE of neonates early, objectively；Relationship exists between ADC values in the brain ofHIE and the site and severity of lesion and the time of imaging examination,ADC valuesmight reflect the degree of brain injury more accurately (7days)；The PLIC and splenium ofcorpus callosum of ADC values than other parts of the brain more accurately reflect thedegree of brain injury of HIE;DWI，ADC values combined with NBNA scores can evaluatethe damage degree and prognosis of cerebral HIE more accurately, objectively. Part Ⅱ DWI on diagnosing and prognosis assessing of prematureinfants with white matter damage Objective To explore the value of DWI on early detecting and prognosis assessing ofpremature infants with white matter damage (WMD).Methods Early features of different types WMD on DWI and conventional MRI wereanalyzed,and imaging changes of WMD and evolution of neuropsychological developmentduring follow-up period were observed.Result On first examination: among32punctuate WMD infants,lesions in semiovalcenter, periventricular white matter clusters or linear high signal on DWI were found in24infants,while only17with short T1and12with short T2signals. DWI showed noabnormality in8infants,with short T1and with or without short T2signal on conventionalMRI. Among11infants with diffuse WMD, DWI showed high signal with periventricularwhite matter, while T1WI/T2WI showed no abnormal signals. On re-examination: MRIshowed no abnormality in18infants with point cluster lesion,among them6had onlywidened outside brain gap. Among14infants with linear or mixedlesions,PVL was defined in7, sequela of PVL were observed in5,while the other2infants showed only widened outsidebrain gap.4infants with diffuse WMD were defined PVL,7were defined as sequela of PVL.The developmental quotience were significant difference among different types of WMD,butnot between linear or mixed punctuate WMD and diffuse WMD.Conclusion DWI can early distinguish different types and evaluate prognosis of WMD.Infants wirh cluster WMD have good prognsis,while those with linear or mixed and diffuseWMD have poor prognsis.