Reliability of cranial CT versus intracerebral pressure measurement for the evaluation of generalised cerebral oedema in children

Objective. To examine the extent to which intracranial pressure (ICP) in ch ildren after severe brain trauma can be determined by cranial CT. Materials and methods. Two experienced paediatric radiologists, without any knowledge of the clinical symptoms, evaluated 124 CT scans from 65 childre n (average age 5.4 years) who underwent intracranial measurement of their c erebral pressure. Results. CT had high sensitivity (99.1%) for 'high cerebral pressure' but a much lower specificity (78.1%). The examiners tended to estimate ICP as 'h igh' even when actual ICP was low. Since therapy for lowering cerebral pres sure involves potential risks, actual cerebral pressure measurement, partic ularly in children, should be considered before intervention (e.g. hyperven tilation or trepanation). We report the change in different intracerebral f luid compartments with varying cerebral pressure and modifications of the d ensity of the brain tissue in an inter- and intraobserver comparison. Conclusion. The radiologist cannot differentiate, for methodological reason s, between a change in the intracranial fluid compartments not associated w ith a change in ICP and one in which it is critically elevated. Before any interventional treatments such as decompression-trepanation or hyperventila tion are instituted, measurement of ICP should be considered, especially in children.