TY - JOUR
T1 - A blinded randomized assessment of laser Doppler flowmetry efficacy in standardizing outcome from intraluminal filament MCAO in the rat
AU - Taninishi, Hideki
AU - Jung, Jin Yong
AU - Izutsu, Miwa
AU - Wang, Zhengfeng
AU - Sheng, Huaxin
AU - Warner, David S.
N1 - Publisher Copyright:
© 2014 Elsevier B.V.
Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2015/2/5
Y1 - 2015/2/5
N2 - 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. Materials and methods: Rats were subjected to 90. min 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±63mm3 vs. 143±86mm3, P=0.24) were not different between groups. Only for one surgeon (novice) did LDF use alter infarct volume (145±28mm3 vs. 98±61mm3, 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. Comparison with existing 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.
AB - 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. Materials and methods: Rats were subjected to 90. min 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±63mm3 vs. 143±86mm3, P=0.24) were not different between groups. Only for one surgeon (novice) did LDF use alter infarct volume (145±28mm3 vs. 98±61mm3, 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. Comparison with existing 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.
KW - Cerebral blood flow
KW - Intraluminal
KW - Laser Doppler flowmetry
KW - Middle cerebral artery occlusion
KW - Stroke
UR - http://www.scopus.com/inward/record.url?scp=84921416999&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84921416999&partnerID=8YFLogxK
U2 - 10.1016/j.jneumeth.2014.12.006
DO - 10.1016/j.jneumeth.2014.12.006
M3 - Article
C2 - 25526908
AN - SCOPUS:84921416999
VL - 241
SP - 111
EP - 120
JO - Journal of Neuroscience Methods
JF - Journal of Neuroscience Methods
SN - 0165-0270
ER -