Evaluation of oedema spreading and intracranial volume reserve using CT image numerical analysis.

Using the cold lesion model vasogenic oedema was produced in 8 cats. The intracranial volume reserve was evaluated applying CT image numerical analysis (CTINA). Summarizing all voxels corresponding to CSF and brain tissue in 8 CT slices, the brain/CSF ratio was computed. The animals were studied at different time intervals after the lesion (2 h, 4 h, 6 h) then sacrificed and the spreading of oedema was estimated based on the BBB disturbances. The brain/CSF ratios varied from mean value of 0.043 in control animals to mean values of 0.022 in animals 6 hours after the lesion. The CTINA method was found very useful as a noninvasive screening method to study brain oedema development with a promising application in clinical practice.