Figure 2
From: From head micro-motions towards CSF dynamics and non-invasive intracranial pressure monitoring
(A) The analysis starts with the pre-processing of the six synchronous signals: the four mechanical signals from the pillow-embedded sensors (ADC units), ECG (mV) and ICP (mmHg). The four-dimensional mechanical β curve is then represented by the one-dimensional k1(t) curvature invariant (ADC∙ms−2). The raw ICP signal is smoothed and time derived yielding dICP (mmHg∙ms-1). The k1(t) and dICP signals are fragmented according to the ECG R-peaks (green vertical lines) into elementary intervals (EI). From each EI only the first 500 ms are considered. (B) Color coding of k1(t) (blue box) and dICP (orange box). C. The Cartan (top) and dICP (middle) map after merging rotated strips side-by-side from left to right; the n-th EI is highlighted in blue and orange, respectively. Bottom: evolution of ICP average value (mmHg). The figure was generated using Adobe Illustrator 2020 (https://www.adobe.com/).
