Intracranial cavity volume can be accurately estimated from the weights ofintracranial contents: confirmation by the dental plaster casting method

Intracranial cavity volume is used to evaluate brain size relative to the i ntracranial space. This volume can theoretically be obtained from the weigh ts and densities of the brain and surrounding cerebrospinal fluid (weight m ethod). However, the accuracy of this method has not been examined. In this study, we examined the reliability of the weight method, by comparing the intracranial cavity volumes of 41 post-mortem cases obtained by the weight method (ICVw) with those obtained by a dental plaster casting method (ICVca st) which was shown to be unbiased. The ICVw was not significantly differen t from the ICV cast (P = 0.49, paired t-test), and the standard error of di fference was 18 ml (1.3% of ICVcast). These results show that the weight me thod is reliable, and applicable to routine autopsies.