RELIABILITY OF BRAIN STRUCTURE MORPHOMETRY IN HYDROCEPHALIC CHILDREN USING MR-IMAGES

To assess the ability of human operators to make decisions about regio n boundaries in significantly malformed brains, we performed a study o f the reliability of morphometric measurements of specific brain struc tures from MRI in children with hydrocephalus and controls, Cross-sect ional area measures of the corpus callosum, internal capsules and cent rum semiovale, and volumes of the lateral ventricles were made in 50 c hildren, Independent measurements were made by two raters on T-1 and T -2-weighted MR images, Pearson's correlation coefficients (r) and intr aclass correlation coefficients (ICC) between the two rater's sets of measures were computed for each structure across all subjects, ICCs ra nged from a low of 0.7502 to a high of 0.9895. All ICCs were significa nt at the p <.0001 level and were generally less than or equal to the corresponding Pearson's r value in every case, Therefore, the Pearson' s r may overestimate the reliability, The results of this study suppor t the claim that the ICC should be used rather than the Pearson's r wh en assessing interater reliability in situations where large between-g roup differences are present, In addition, the results show that brain s malformed by disorders, such as hydrocephalus, can be reliably asses sed using morphometric measures of MR images.