The Application Of MR Susceptibility Weighted Imaging In Neonatal Brain Injury

Part?The application of MR susceptibility weighted imaging in normal neonatal brainObjective:To investigate the the appearance of normal neonatal brain on susceptibility weighted imaging.Methods:Ten neonates without high risks of brain injury and the manifestation of neonatal brain injury were examined with a 1.5T MR imaging system (Avanto; Siemens, Erlangen, Germany). All of 10 neonates were performed with conventional MRI sequences and SWI. The routine MR imaging protocol included sagittal and transverse T1-weighted, transverse T2-weighted, transverse Flair(fluid-attenuated inversion recovery) and transverse diffusion-weighted imaging. There were no abnormal appearances on conventional MRI. Among of 10 neonates,5 neonates were preterm at term-equivalent age, another 5 neonates were term neonates. The acquisition time of SWI was 3 minutes and 29 seconds. To assess appearance and signal-intensity changes of the healthy neonatal brain on SWI.Results:All of 10 neonates were successfully performed with conventional MRI sequences and SWI. The cerebral parenchyma has intermediate signal intensity with loss of gray/white matter differentiation. There is partial suppression of cerebrospinal fluid (CSF) signal with the ventricles of intermediate signal, slightly hypointense to brain. The small cortical veins are seen as linear hypointensities. The MinIP images improve visualisation of cortical veins and demonstrates their tubular nature enabling differentiation from focal hemorrhagic lesions. Conclusions:There was no evidence difference on SWI between preterm at term-equivalent age and term neonates. The cortical veins are hypointense on SWI, and there no other hypointense in pararenchyma of neonatal brain.The MinIP images improve visualisation of veins. Part?The application of MR susceptibility weighted imaging in intracranial hemorrhage of neonateObjective To evaluate neonatal intracranial hemorrhage with susceptibility weighted imaging (SWI), and to explore the value and limitation of SWI compared with conventional magnetic resonance imageing.Materials and Methods We conducted a prospective study including 596 neonates who were suspected injury of brin. All MR examinations were performed at 1.5 Tesla unit including conventional MR(T1, T2 and Flair sequences), DWI and SWI. Among 596 neonates there were 134 neonates with intracranial hemorrhage detected on routine MRI sequence and/or SWI.Among neonates with intracranial hemorrhage there were 81 preterm and 53 term neonates. To access neonatal intracranial hemorrhage appearance on SWI, and compare the numbers and areas of hemorrhage on conventional MRI sequences and SWI.Results Among 134 neonates with intracranial hemorrhage, there were only 19 case showed extracerebral hemorrhage (17 cases subdural hemorrhage, and 1 case extradural hemorrhage with subarachnoid hemorrhage, and 1 case extradural hemorrhage), all 19 cases were showed on SWI, and 1 case with subdural hemorrhage did not showed on conventional MRI sequences.115 case were detected with parenchymal hemorrhage, and among them 16 cases did not be detected on conventional MRI sequences.98 cases with parenchymal hemorrhage were measured the maximal areas, the maximal areas of hemorrhage was larger on SWI than conventional,the statistical differences were considered as statistically significant (Z =-8.337, P<0.01). Six areas of germinal matrix hemorrhage/intraventricular hemorrhage, except the hemorrhage of aqueduct of mesencephalon, other 5 areas with hemorrhage were deteced more cases on SWI than conventional MRI sequences, the statistical differences were considered as statistically significant (P<0.05).SWI detected more cases with subarachnoid hemorrhage than conventional MRI sequences. There was no significant differences when compared subdural hemorrhage and extradural hemorrhage detected on SWI and conventional MRI.Conclusions:SWI is a potent examination for cerebral bleeding displaying due to the higher sensitivity compared with the other conventional MRI sequences, and has predominant advantage over conventional MRI sequences in detecting intracranial hemorrhage of neonatePart?The application of MR susceptibility weighted imaging in neonatal white matter injuryObjective:To evaluate neonatal white matter injuty (punctate white matter lesions and periventricular leukomalacia) in neonatal brain injury with susceptibility weighted imaging,and to explore the value and limitation of SWI compared with conventional magnetic resonance imageing.Materials and Methods:We conducted a prospective study including 64 neonates presenting with PWML and 29 neonates presenting with periventricular leukomalacia at first MRI. All MR examinations were performed at 1.5 Tesla unit including conventional MR (T1, T2 and Flair sequences), DW1 and SWI. PWML were defined as punctuate lesions with T1 hyperintensity and T2 isointensity or hypointensity in the white matter. Among neonates with PWML there were 34 preterm and 30 term neonates. PWML were classified into two groups:1) T1 hyperintensity and T2 isointensity; 2) T1 hyperintensity and T2 hypointensity. To analyze whether two groups of PWML contains hemorrhage on SWI. Among neonates with PVL there were 24 preterm and 5 term neonates. To accesse whether PVL contains hemorrhage and/or collateral vein on SWI.Results:Among all cases of PWML, there are only 6 cases (9.4%) showed evidence of hemorrhage on SWI. There were 17 cases in group 1, only 1 case showed punctate hypointensity in the areas of PWML on SWI, and other 16 cases showed no hemorrhage on SWI.47 cases were in group 2, only 5 cases showed evidence of hemorrhage on SWI, and other 42 cases were absent hemorrhage on SWI. Among 29 cases with PVL, there were 6 (20.7%) cases showed punctate hypointensity in the areas of PVL on SWI, and other 23 cases were abent hemorrhage on SWI. There were 18 (62.1%) cases showed collateral vein in the areas of PVL on SWI, and other 11 cases were abent collateral vein in the areas of PVL on SWI.Conclusion:Most areas of PWML in neonatal brain showed no hemorrhage on SWI. SWI can help identify whether PWML of neonates contains hemorrhage. SWI also can help identify whether PVL of neonates contains hemorrhage and collateral vein.