Fig. 1
Telemetric system and implantation of telemeter: a ICP was measured by Kaha Sciences rat telemetry system (Kaha Sciences Ltd, Auckland, New Zealand). The system consists of an ICP telemeter for pressure measurement which is implanted in the animal. Implanted animals are then housed in their home cage placed on a SmartPad (in blue) with the possibility to co-house two implanted animals. The SmartPad functions as a power supply and wireless link to the telemeter for wireless data transmission. This system enables digital data transmission, wireless inductive power supply and 24/7 digital data collection from telemeters implanted in freely-moving, conscious animals living in their home cages. The ICP signal obtained is relative to the room pressure at that time. Images are reproduced with permission from Kaha Sciences. b Schematic illustration of the epidural placement of the sensor tip (black) and two anchoring screws (grey) localized in relation to Bregma. The image to the right obtained from the surgical procedure showing the beveled drill/thinned hole for the sensor tip and the two screws. The drill hole for the epidural sensor tip is made without penetrating dura mater. c Study design of the short-term study with a recovery period (RP) followed by a physiological period (PP). d Non-continuous individual daily mean ICP values for each of the rats included in the short-term ICP monitoring study (n = 4). The ICP measurements were obtained in a daily time-window of 2–5 h from day 0 or day 2 post-surgery and continued for up to day 15. Each dot represents the mean ICP value of each rat on the given day. The dotted line represents zero pressure