title: In vitro study of cerebrospinal fluid dynamics in a shaken basal cistern after experimental subarachnoid hemorrhage.
abstract: BACKGROUND
  Cerebral arterial vasospasm leads to delayed cerebral ischemia and constitutes the major delayed complication following aneurysmal subarachnoid hemorrhage. Cerebral vasospasm can be reduced by increased blood clearance from the subarachnoid space. Clinical pilot studies allow the hypothesis that the clearance of subarachnoid blood is facilitated by means of head shaking. A major obstacle for meaningful clinical studies is the lack of data on appropriate parameters of head shaking. Our in vitro study aims to provide these essential parameters.
  
  
  RESULTS
  A model of the basal cerebral cistern was derived from human magnetic resonance imaging data. Subarachnoid hemorrhage was simulated by addition of dyed experimental blood to transparent experimental cerebrospinal fluid (CSF) filling the model of the basal cerebral cistern. Effects of various head positions and head motion settings (shaking angle amplitudes and shaking frequencies) on blood clearance were investigated using the quantitative dye washout method. Blood washout can be divided into two phases: Blood/CSF mixing and clearance. The major effect of shaking consists in better mixing of blood and CSF thereby increasing clearance rate. Without shaking, blood/CSF mixing and blood clearance in the basal cerebral cistern are hampered by differences in density and viscosity of blood and CSF. Blood clearance increases with decreased shaking frequency and with increased shaking angle amplitude. Head shaking facilitates clearance by varying the direction of gravitational force.
  
  
  CONCLUSIONS
  From this in vitro study can be inferred that patient or head shaking with large shaking angles at low frequency is a promising therapeutic strategy to increase blood clearance from the subarachnoid space.
authors.affiliation: Biofluid Mechanics Laboratory, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kertzscher
authors.forename: Torsten
authors.initials: T
authors.lastname: Schneider
authors.forename: Leonid
authors.initials: L
authors.lastname: Goubergrits
authors.forename: Klaus
authors.initials: K
authors.lastname: Affeld
authors.forename: Daniel
authors.initials: D
authors.lastname: Hänggi
authors.forename: Andreas
authors.initials: A
authors.lastname: Spuler
mesh_terms: D000328:Adult; D002555:Cerebrospinal Fluid / Q000000981:diagnostic imaging*; D006112:Gravitation; D006257:Head / Q000000981:diagnostic imaging; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D008297:Male; D008954:Models, Biological; D009038:Motion; D019047:Phantoms, Imaging; D011859:Radiography; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging*