Polygraphic studies in 30 patients with recent closed cranial injuries revealed rare correlations between intracranial pressure (ICP) and EEG findings in cases of lower cerebral dysfunction, while higher-level dysfunction showed more consistent correlations.
Delta waves (type A) typically indicate low ICP levels, whereas rapid, low voltage EEG patterns (type B) are linked with elevated ICP, with type C tracing potentially following type B as ICP rises.
The observed EEG changes are likely connected to the underlying brain pathology rather than direct effects from ICP fluctuations, similar to changes seen in conditions like intracranial tumors or hydrocephalus.