title: A blinded randomized assessment of laser Doppler flowmetry efficacy in standardizing outcome from intraluminal filament MCAO in the rat.
abstract: BACKGROUND
  Laser Doppler flowmetry (LDF) is widely used for estimating cerebral blood flow changes during intraluminal middle cerebral artery occlusion (MCAO). No investigation has systematically examined LDF efficacy in standardizing outcome. We examined MCAO histologic and behavioral outcome as a function of LDF measurement.
  
  
  METHODS
  Rats were subjected to 90min MCAO by 4 surgeons having different levels of MCAO surgical experience. LDF was measured in all rats during ischemia. By random assignment, LDF values were (Assisted) or were not (Blinded) made available to each surgeon during MCAO (n=12-17 per group). Neurologic and histologic outcomes were measured 7 days post-MCAO. A second study examined LDF effects on 1-day post-MCAO outcome.
  
  
  RESULTS
  Pooled across surgeons, intra-ischemic %LDF change (P=0.12), neurologic scores (Assisted vs. Blinded=14±6 vs. 13±7, P=0.61, mean±standard deviation) and cerebral infarct volume (162±63mm(3)vs. 143±86mm(3), P=0.24) were not different between groups. Only for one surgeon (novice) did LDF use alter infarct volume (145±28mm(3)vs. 98±61mm(3), P=0.03). LDF use decreased infarct volume coefficient of variation (COV) by 35% (P=0.02), but had no effect on neurologic score COV.
  
  
  METHODS
  We compared intraluminal MCAO outcome as a function of LDF use.
  
  
  CONCLUSIONS
  LDF measurement altered neither neurologic nor histologic MCAO outcome. LDF did not decrease neurologic deficit COV, but did decrease infarct volume COV. LDF may allow use of fewer animals if infarct volume is the primary dependent variable, but is unlikely to impact requisite sample sizes if neurologic function is of primary interest.
authors.affiliation: Multidisciplinary Neuroprotection Laboratories, Duke University Medical Center, Durham, NC, United States; Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States.
authors.forename: Hideki
authors.initials: H
authors.lastname: Taninishi
authors.affiliation: Multidisciplinary Neuroprotection Laboratories, Duke University Medical Center, Durham, NC, United States; Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States.
authors.forename: Jin Yong
authors.initials: JY
authors.lastname: Jung
authors.affiliation: Multidisciplinary Neuroprotection Laboratories, Duke University Medical Center, Durham, NC, United States; Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States.
authors.forename: Miwa
authors.initials: M
authors.lastname: Izutsu
authors.affiliation: Multidisciplinary Neuroprotection Laboratories, Duke University Medical Center, Durham, NC, United States; Department of Surgery, Duke University Medical Center, Durham, NC, United States.
authors.forename: Zhengfeng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Multidisciplinary Neuroprotection Laboratories, Duke University Medical Center, Durham, NC, United States; Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States.
authors.forename: Huaxin
authors.initials: H
authors.lastname: Sheng
authors.affiliation: Multidisciplinary Neuroprotection Laboratories, Duke University Medical Center, Durham, NC, United States; Department of Anesthesiology, Duke University Medical Center, Durham, NC, United States; Department of Surgery, Duke University Medical Center, Durham, NC, United States; Department of Neurobiology, Duke University Medical Center, Durham, NC, United States. Electronic address: david.warner@duke.edu.
authors.forename: David S
authors.initials: DS
authors.lastname: Warner
mesh_terms: D000818:Animals; D020244:Infarction, Middle Cerebral Artery / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D017078:Laser-Doppler Flowmetry / Q000592:standards* / Q000706:statistics & numerical data; D008297:Male; D009757:Nylons / Q000009:adverse effects; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016037:Single-Blind Method
chemical_list: D009757:Nylons
keywords: Cerebral blood flow; Intraluminal; Laser Doppler flowmetry; Middle cerebral artery occlusion; Stroke