Value of fluid-attenuated inversion recovery sequences in early MRI of thebrain in neonates with a perinatal hypoxic-ischemic encephalopathy

The aim of our study was to assess the usefulness of fluid-attenuated inver sion recovery (FLAIR) sequences in comparison with conventional spin-echo a nd inversion MR imaging in neonates for evaluation of myelination and for d etection of hypoxic-ischemic brain injury. We reviewed early MR scans of 18 neonates with suspected hypoxic-ischemic brain damage. Myelination could b e evaluated with confidence using conventional MR imaging in all but 2 infa nts; however, the presence of myelin was very difficult to assess on FLAIR images. Overall, 53 lesions or groups of lesions were identified. The FLAIR technique was more sensitive in 11 of the lesions; especially (pre)cystic lesions could be identified much better and more cysts were found. Conventi onal MR imaging failed to identify 2 of the lesions and was more sensitive in 14 of the lesions; especially punctate hemorrhages and lesions in basal ganglia or thalami could be better determined. The FLAIR technique missed 3 of these lesions. In the remaining 28 lesions conventional MR and FLAIR im ages were equally diagnostic. The FLAIR technique and conventional MR imagi ng are complementary in detecting early sequelae of hypoxic-ischemic brain injury in neonates. The FLAIR technique is not suitable I for assessing mye lination of the neonatal brain; therefore, FLAIR cannot replace conventiona l MR imaging.