Fig.1.
Illustration of a raw ICP recording, its low-pass filtered and its band-pass filtered versions. The band-pass filter was designed based on heart rate for the purpose of simplifying the morphology of ICP pulse so that only one peak is preserved in the filtered signal. The low-pass filter is a moderate 2nd order 5 Hz zero-phase Elliptic filter. It removes high frequency noise but has minimal influence on the onset location of ICP pulse.