title: Effects of changes in power setting of an ultrasonic aspirator on amount of damage to the cerebral cortex of healthy dogs.
abstract: OBJECTIVE
  To determine the minimal ultrasonic aspirator pressure necessary to damage the cerebral cortex of healthy dogs.
  
  
  METHODS
  9 mixed-breed dogs.
  
  
  METHODS
  The study comprised 2 parts. In part A, 6 dogs were euthanatized immediately prior to the experiment. In part B, 3 dogs were anesthetized for recording of physiologic variables. In both parts, craniectomy and durotomy were performed to bilaterally expose the lateral aspect of the cerebral cortex. An ultrasonic aspirator was placed in contact with various areas of the cerebral cortex, and aspirator power was altered (10, 20, 30, and 40%). Duration of contact at each power was 5 and 10 seconds. Subsequently, gross morphologic and histologic damage was assessed in the cortex.
  
  
  RESULTS
  Gross observations for all dogs were similar. At 10% power, visible or histologic damage was not evident in the cortex. At 20% power, the cortex was slightly indented from contact with the hand piece; however, cortical disruption was not evident. Cortical disruption was initially detectable at 30% power in some dogs and was consistently evident at 40% power in both sets of dogs.
  
  
  CONCLUSIONS
  Ultrasonic aspirator power of < 20% created minimal acute morphologic damage to the cortex. Power settings between 20 and 30% may superficially damage the cerebral cortex in healthy dogs, whereas 40% power consistently damages the cerebral cortex. Knowledge of the degree of damage to cerebral cortex caused by various amounts of power for ultrasonic aspirators will allow surgeons to avoid damaging normal brain tissues during surgery.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman 99164-6610, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: Bagley
authors.forename: M L
authors.initials: ML
authors.lastname: Harrington
authors.forename: J M
authors.initials: JM
authors.lastname: Gay
authors.forename: G M
authors.initials: GM
authors.lastname: Silver
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000293:injuries*; D004285:Dogs; D011312:Pressure / Q000009:adverse effects; D013396:Suction / Q000009:adverse effects / Q000295:instrumentation / Q000662:veterinary*; D014465:Ultrasonics / Q000009:adverse effects*