CHANGES IN DURAL THICKNESS REFLECT CHANGES IN INTRACRANIAL-PRESSURE IN DOGS

The thickness of the dura mater was obtained from ultrasound probes on the skull and fast Fourier transform-Cepstrum through a probability p rocess at various intracranial pressures (ICP), measured with pressure transducers, in 12 anesthetized dogs, There was a constant relationsh ip between changes in thickness (mu m) and changes in ICP (mmHg) from 5 to 80 mmHg. The estimated thickness at 0 mmHg of pressure and values obtained from measurements of dural samples were very similar. Our me thod provides estimations of ICP, and holds promise for measuring thic knesses below 1000 mu m in biological systems in general.