Early monitoring of cerebral hypoperfusion in rats by laser speckle imaging and functional photoacoustic microscopy.
Because cerebral hypoperfusion brings damage to the brain, prevention of cerebrovascular diseases correlative to hypoperfusion by studying animal models makes great sense. Since complicated cerebrovascular adaptive changes in hypoperfusion could not be revealed only by cerebral blood flow (CBF) velocity imaging, we performed multi-parameter imaging by combining laser speckle imaging and functional photoacoustic microscopy. The changes in CBF, hemoglobin oxygen saturation (SO(2)), and total hemoglobin concentration (HbT) in single blood vessels of ipsilateral cortex were observed during transient cerebral hypoperfusion by ligating the unilateral common carotid artery in rats. CBF, SO(2), and HbT, respectively, decreased to 37 ± 3%, 71 ± 7.5%, and 92 ± 1.3% of baseline in 6 s immediately after occlusion, and then recovered to 77 ± 4.8%, 84 ± 8%, and 96 ± 2% of baseline in 60 s. These parameters presented the decrease with different degree and the following recovery over time after ligation, the recovery of SO(2) lagged behind those of CBF and HbT, which had the similar response. The results demonstrated that complete monitoring of both cerebral hemodynamic response and oxygen metabolic changes occurred at the earliest period of cerebral hypoperfusion was possible by using the two image modalities with high temporal and spatial resolution.
Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, 1037 Luoyu Road, Wuhan 430074, China.
Hui
H
Wang
Xiaoquan
X
Yang
Zhen
Z
Wang
Zilin
Z
Deng
Hui
H
Gong
Qingming
Q
Luo
D000465:Algorithms; D000818:Animals; D001921:Brain / Q000378:metabolism; D017536:Carotid Artery, Common / Q000473:pathology; D002540:Cerebral Cortex / Q000098:blood supply; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000175:diagnosis*; D003952:Diagnostic Imaging / Q000379:methods*; D004867:Equipment Design; D006439:Hemodynamics; D006454:Hemoglobins / Q000378:metabolism; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007834:Lasers; D008297:Male; D033401:Microscopy, Acoustic / Q000379:methods*; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D061088:Photoacoustic Techniques / Q000379:methods*; D051381:Rats; D017208:Rats, Wistar
D006454:Hemoglobins; D010100:Oxygen