EARLY PATTERN-RECOGNITION IN SEVERE PERINATAL ASPHYXIA - A PROSPECTIVE MRI STUDY

On the basis of MRI examinations in 88 neonates and infants with perin atal asphyxia, we defined 6 different patterns on T2-weighted images: pattern A - scattered hyperintensity of both hemispheres of the telenc ephalon with blurred border zones between cortex and white matter, ind icating diffuse brain injury; pattern B - parasagittal hyperintensity extending into the corona radiata, corresponding to the watershed zone s; pattern C - hyper- and hypointense lesions in thalamus and basal ga nglia, which relate to haemorrhagic necrosis or iron deposition i n th ese areas; pattern D - periventricular hyperintensity, mainly along th e lateral ventricles, i.e. periventricular leukomalacia (PVL), origina ting from the matrix zone; pattern E - small multifocal lesions varyin g from hyper- to hypointense, interpreted as necrosis and haemorrhage; pattern F - periventricular centrifugal hypointense stripes in the ce ntrum semiovale and deep white matter of the frontal and occipital lob es. Contrast was effectively inverted on T1-weighted images. Patterns A, B and C were found in 17 %, 25 % and 37 % of patients, and patterns D, E and F in 19 %,17 % and 35 %, respectively. In 49 patients a comb ination of patterns was observed, but 30% of the initial images were n ormal. At follow-up, persistent abnormalities were seen in all childre n with patterns A and D, but in only 52 % of those with pattern C. Mye lination was retarded most often in patients with diffuse brain injury and PVL (patterns A and D).