title: Magnetic resonance flow velocity and temperature mapping of a shape memory polymer foam device.
abstract: BACKGROUND
  Interventional medical devices based on thermally responsive shape memory polymer (SMP) are under development to treat stroke victims. The goals of these catheter-delivered devices include re-establishing blood flow in occluded arteries and preventing aneurysm rupture. Because these devices alter the hemodynamics and dissipate thermal energy during the therapeutic procedure, a first step in the device development process is to investigate fluid velocity and temperature changes following device deployment.
  
  
  METHODS
  A laser-heated SMP foam device was deployed in a simplified in vitro vascular model. Magnetic resonance imaging (MRI) techniques were used to assess the fluid dynamics and thermal changes associated with device deployment.
  
  
  RESULTS
  Spatial maps of the steady-state fluid velocity and temperature change inside and outside the laser-heated SMP foam device were acquired.
  
  
  CONCLUSIONS
  Though non-physiological conditions were used in this initial study, the utility of MRI in the development of a thermally-activated SMP foam device has been demonstrated.
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA. small3@llnl.gov
authors.forename: Ward
authors.initials: W
authors.lastname: Small
authors.forename: Erica
authors.initials: E
authors.lastname: Gjersing
authors.forename: Julie L
authors.initials: JL
authors.lastname: Herberg
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Wilson
authors.forename: Duncan J
authors.initials: DJ
authors.lastname: Maitland
mesh_terms: D013504:Cardiovascular Surgical Procedures / Q000295:instrumentation*; D003485:Cyanates; D004983:Ethanolamines; D005029:Ethylenediamines; D017953:Isocyanates; D007834:Lasers; D008279:Magnetic Resonance Imaging; D008422:Materials Testing; D011108:Polymers; D012212:Rheology; D013696:Temperature
chemical_list: D003485:Cyanates; D004983:Ethanolamines; D005029:Ethylenediamines; D017953:Isocyanates; D011108:Polymers; C015262:1,6-hexamethylene diisocyanate; C010629:1,1',1'',1'''-(ethylenedinitrilo)tetra-2-propanol; C009546:triethanolamine