Special Article

The neonatal brain, previously so inviolate to imaging techniques other than relatively crude radionuc lide studies , direct contrast ventriculography, and rarely performed angiography or pneumoencephalography by only the most adventuresome or experienced neuroradiolog ists , now has been successfully and safely mastered by computed tomography (CT) and sonography. Widespread interest in and clinical importance of images so obtained has dramatically altered and improved diagnostic expertise and understanding in these most difficult of all patients. The main features influencing the clinical and diagnostic efficacy of such imaging methods are: (1) their individual spatial resolution, (2) the reliability of each technique vis a vis each other, (3) their relative safety and ease of performance, and (4) a suitable imaging protocol. An awareness is essential of the complex cerebra l seq uelae that can afflict neonates, thei r unique cerebral anatomy, the differences between preterm and term babies, the differing type and degree of cerebral damage in the preterm and term baby, and the long-term clinical sequelae from each type of disease at each level of maturity, The neonate, particularly if premature , may have sign ificant respiratory (e.g ., respiratory distress syndrome) and intraabdominal (e.g., necrotizing enteroco liti s) abnormalities in concert with cerebral damage. This latter damage may be varying ischemic changes, intracerebral hemorrhage, or both . Mortality may be influenced by one or more of the above disease processes, and it is often ultimately difficult to identify which is the prime agent. The treatment of one, such as respiratory distress syndrome, may create the c ircumstance for formation of another (e.g., cerebral hemorrhage). An understanding of the basic features of fetal cerebral anatomy and the pathogenesis, morphology, and c linical sign ificance of acqu ired postnatal cerebral abnormalities shou ld precede the suggestion of a logical diag nosti c imaging protocol. Abnormalities not associated wi th the birth process per se, such as congenital malformations and neoplasms, deem separate consideration and are not included here.