Pediatric neuroimaging in pre-CT era: back to the future

Over the last half a century, diagnostic neuroimaging has made tremendous strides following the introduction of computerized tomography (CT) and subsequent magnetic resonance imaging (MR). Prior to that time, the neurological diagnosis was conducted with careful history taking, physical examinations, and invasive testing such as cerebral angiography, encephalography, and myelography. Techniques and contrast media for these tests have been refined and progressed over time. However, these invasive tests have diminished and are rarely used for daily practice in pediatric neurosurgery since the introduction of CT and MR. Nuclear brain scan and ultrasonography are non-invasive. A nuclear brain scan using radioactive tracers was used to demonstrate the laterality of the lesion without an intact blood-brain barrier, but was rarely performed after the CT era. On the other hand, improved ultrasonography made strides because of its portability and the lack of radiation exposure and sedation. It is often a first-line investigatory tool for neonatal evaluation. This article describes a review of developments and progresses of pediatric neuroimaging in the pre-CT era.