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Background and Purpose: Neurologic and developmental outcomes of asphyxiated, term neonates are difficult to predict applying clinical or laboratory criteria. In this study, we investigated the association of MR spectroscopy (MRS) results with neurodevelopmental status at age 12 months., Method: Thirty-one term neonates, who were enrolled in a prospective study of the utility of MR imaging for the determination of neurologic and developmental status, underwent single-voxel proton MRS of the basal nuclei and intervascular boundary zones. Ratios of lactate, choline, creatine, and N-acetylaspartate (NAA) peaks were calculated and tested for association with neuromotor scores and Mental Development Index of the Bayley Scores of Infant Development obtained at age 12 months., Results: Elevated lactate and diminished NAA were the most common findings in infants with neurologic and developmental abnormalities at age 12 months. Although many ratios had statistically significant associations with outcome (P<.05), the highest significance was obtained with lactate/choline ratios in the basal nuclei. A false-positive finding was seen in a patient who was born after a 36-week gestation period (high lactate/choline but normal neurodevelopmental status at 12 months) and in three patients with apparent watershed injury (high watershed lactate/choline but normal neurodevelopmental status at 12 months). A false-negative MRS finding (normal lactate/choline but abnormal outcome) was seen in a patient who had an apparent prenatal injury., Conclusion: Proton MRS appears to be a useful tool for assessing brain injury in neonates who have suffered hypoxia or ischemia. Correlation with gestational age and imaging findings are essential for proper interpretation of the spectra. Patients with apparent watershed injuries may have normal neurodevelopmental status at age 12 months.

Purpose: We developed a scoring system for the assessment of perinatal asphyxia as depicted on MR images., Methods: Four scoring systems were derived to evaluate MR images obtained in asphyxiated neonates: the basal ganglia (BG) score, the watershed (W) score, the combined basal ganglia/watershed (BG/W) score, and the sum of the BG and W scores, the summation (S) score. In addition, three MR sequences, T1-weighted, first-echo T2-weighted, and second-echo T2-weighted, were assessed for each patient for each scoring system. Neuromotor examinations were performed at ages 3 and 12 months, and cognitive development was tested at age 12 months. Statistical analysis was then performed to test the relationship between the MR scores and the outcome scores., Results: The BG/W score, obtained with the first-echo T2-weighted sequence, was the most useful overall score for predicting neuromotor outcome at 3 and 12 months and cognitive outcome at 12 months. T1-weighted and first-echo T2-weighted sequences showed a stronger association with outcome in patients imaged during the first postnatal week, whereas second-echo T2-weighted sequences showed a stronger association with outcome in patients imaged during the second postnatal week., Conclusion: It appears that, with the use of the BG/W score, MR imaging discriminates accurately between patients with good and poor neuromotor and cognitive outcome at 3 and 12 months. In terms of our scoring systems, the first-echo T2-weighted sequence appears to discriminate best between patients with good and poor 3- and 12-month outcomes. Proper use of the imaging sequences and scoring systems described in this article can increase the knowledge base upon which treatment decisions are made in asphyxiated neonates.

Purpose: To determine the pattern of enhancement on contrast-enhanced MR studies of the brain in neonates., Methods: Contrast-enhanced brain MR studies of 16 neonates were reviewed retrospectively. All infants had normal neonatal courses, normal noncontrast MR findings, and normal neurologic examinations at age 12 months. All enhancing regions within the brain, dura, calvaria, and orbits were recorded. An enhancement factor, F = (Ic-Ip)/Ip, was calculated from region-of-interest intensity measurements in five regions of each hemisphere (basal ganglia, thalami, and three hemispheric locations), where Ic was signal intensity after contrast administration and Ip was the noncontrast signal intensity for each region., Results: Enhancement was detected in the choroid plexus, pituitary infundibula, pineal glands, dura, veins and venous sinuses, cranial sutures, and irises of the orbital globes. No enhancement of the brain parenchyma was detected by visual inspection, although some change in signal intensity of the cerebral parenchyma was detected by the region-of-interest intensity measurements, with enhancement factors ranging from 0 to 0.08 (mean, 0.04). No consistent regional variation in enhancement was detected. Because the degree of enhancement was identical to that in the normal adult brain, the slight enhancement detected was attributed to contrast material in capillaries and small venules., Conclusion: In addition to the expected findings of enhancement of the pituitary stalk, the pineal gland, the choroid plexus, the dura, and the cerebral veins, we detected enhancement of the calvarial sutures and ocular irises. No evidence of enhancement of the cerebral parenchyma was detected, suggesting that the blood-brain barrier to gadolinium chelates is intact in the neonatal brain.