title: A novel method for long-term monitoring of intracranial pressure in rats.
abstract: BACKGROUND
  In preclinical neurological studies, monitoring intracranial pressure (ICP) in animal models especially in rodents is challenging. Further, the lack of methods for long-term ICP monitoring has limited the possibilities to conduct prolonged studies on ICP fluctuations in parallel to disease progression or therapeutic interventions. For these reasons we aimed to set up a simple and valid method for long-term ICP recordings in rats.
  
  
  METHODS
  A novel ICP method employing epidural probes was developed and validated by simultaneously ICP recordings in the lateral ventricle and in the epidural space. The two pressures were recorded twice a week for 59 days and the correlation was studied.
  
  
  RESULTS
  The two pressure recordings correlated exceptionally well and the R(2) values on each recording day ranged between 0.99 and 1.00. However, the ventricular probes caused a number of complications including loss of patency and tissue damage probably due to cerebral infection, whereas the epidural probes were safe and reliable throughout the entire study.
  
  
  METHODS
  Epidural probes are much easier to implant than ventricular probes. In addition, these new probes are far less invasive and induce no apparent mechanical tissue damage and highly decrease the infection risk associated with ICP recordings.
  
  
  CONCLUSIONS
  Epidural ICP recorded with this new method is identical to the ventricular ICP for at least 59 days but is far less complicated and safer for the animals. The long-term method described is reliable, valid, inexpensive, and may be used in multiple disease models to study ICP.
authors: Danish Headache Center, Building 24, Department of Neurology, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 69, 2600 Glostrup, Denmark; Research Institute, Danish Headache Center, Glostrup, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 69, 2600 Glostrup, Denmark.
authors: Maria
authors: M
authors: Uldall
authors: Department of Neurosurgery, The National Hospital, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark.
authors: Marianne
authors: M
authors: Juhler
authors: Department of Neurosurgery, The National Hospital, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark.
authors: Anders Daehli
authors: AD
authors: Skjolding
authors: Research Institute, Danish Headache Center, Glostrup, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 69, 2600 Glostrup, Denmark; Department of Neurology, Herlev Hospital, University of Copenhagen, Herlev Ringvej 75, 2730 Herlev, Denmark.
authors: Christina
authors: C
authors: Kruuse
authors: Danish Headache Center, Building 24, Department of Neurology, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 69, 2600 Glostrup, Denmark; Research Institute, Danish Headache Center, Glostrup, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 69, 2600 Glostrup, Denmark.
authors: Inger
authors: I
authors: Jansen-Olesen
authors: Danish Headache Center, Building 24, Department of Neurology, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 69, 2600 Glostrup, Denmark. Electronic address: rigmor.jensen@regionh.dk.
authors: Rigmor
authors: R
authors: Jensen
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D004824:Epidural Space / Q000502:physiology; D005260:Female; D007427:Intracranial Pressure / Q000502:physiology*; D020547:Lateral Ventricles / Q000502:physiology; D016014:Linear Models; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D013997:Time Factors
keywords: Animal model; CSF pressure; Epidural; Intracranial pressure; Rat; Ventricular