title: Assessment of rat sciatic nerve function following acute implantation of high density Utah slanted electrode array (25 electrodes/mm(2) ) based on neural recordings and evoked muscle activity.
abstract: BACKGROUND
  High density Utah slanted electrode arrays (HD-USEAs) have been developed recently for intrafascicular access to submillimeter neural structures. Insertion of such high electrode density devices may cause nerve crush injury, counteracting the intended improved selective nerve fiber access.
  
  
  METHODS
  HD-USEAs were implanted into sciatic nerves of anesthetized rats. Nerve function was assessed before and after HD-USEA implantation by measuring changes in evoked muscle and nerve compound action potentials and single unit neuronal recordings.
  
  
  RESULTS
  Neural activity was recorded with over half of all implanted electrodes. Average decreases of 38%, 36%, and 13% in nerve, medial gastrocnemius, and tibialis anterior compound action potential amplitudes, respectively, were observed following array implantation. Only 1 of 8 implantations resulted in loss of all signals.
  
  
  CONCLUSIONS
  These studies demonstrate that HD-USEAs provide a useful neural interface without causing a nerve crush injury that would otherwise negate their use in acute preparations (<12 h).
authors.affiliation: Department of Bioengineering, 20 S. 2030 E, Room 506F, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Kiran S
authors.initials: KS
authors.lastname: Mathews
authors.forename: Heather A C
authors.initials: HA
authors.lastname: Wark
authors.forename: Richard A
authors.initials: RA
authors.lastname: Normann
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D004567:Electrodes, Implanted; D055724:Electrophysiological Phenomena / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology; D005528:Foot / Q000294:innervation / Q000502:physiology; D008839:Microelectrodes; D018482:Muscle, Skeletal / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000502:physiology*
keywords: compound action potential; intrafascicular; microelectrodes; rat; sciatic nerve