TY - JOUR
T1 - Modifying the ICP pulse wave
T2 - effects on parenchymal blood flow pulsatility
AU - Qvarlander, Sara
AU - Dombrowski, Stephen M.
AU - Biswas, Dipankar
AU - Thyagaraj, Suraj
AU - Loth, Francis
AU - Yang, Jun
AU - Luciano, Mark G.
N1 - Publisher Copyright:
© 2023 the American Physiological Society.
PY - 2023/2
Y1 - 2023/2
N2 - Pulsation of the cerebral blood flow (CBF) produces intercranial pressure (ICP) waves. The aim of this study is to determine whether externally modifying ICP pulsatility alters parenchymal blood flow pulsatility. A cardiac-gated inflatable device was inserted in the lateral epidural space of 12 anesthetized canines (canis familiaris) and used to cause reduction, inversion, and augmentation of the ICP pulse. CBF in each hemisphere was measured using laser Doppler velocimetry. A significant increase in both mean CBF and its amplitude was observed for reduction as well as inversion of the ICP pulse, with larger changes observed for the inversion protocol. Significant increases in the mean CBF were also observed ipsilaterally for the augmentation protocol together with indications of reduced CBF amplitude contralaterally. External alteration of the ICP pulse thus caused significant changes in parenchymal blood flow pulsatility. The inverse relationship between the ICP and CBF amplitude suggests that the changes did not occur via modification of the intracranial Windkessel mechanism. Thus, the effects likely occurred in the low-pressure vessels, i.e., capillaries and/or venules, rather than the high-pressure arteries. Future MRI studies are however required to map and quantify the effects on global cerebral blood flow.
AB - Pulsation of the cerebral blood flow (CBF) produces intercranial pressure (ICP) waves. The aim of this study is to determine whether externally modifying ICP pulsatility alters parenchymal blood flow pulsatility. A cardiac-gated inflatable device was inserted in the lateral epidural space of 12 anesthetized canines (canis familiaris) and used to cause reduction, inversion, and augmentation of the ICP pulse. CBF in each hemisphere was measured using laser Doppler velocimetry. A significant increase in both mean CBF and its amplitude was observed for reduction as well as inversion of the ICP pulse, with larger changes observed for the inversion protocol. Significant increases in the mean CBF were also observed ipsilaterally for the augmentation protocol together with indications of reduced CBF amplitude contralaterally. External alteration of the ICP pulse thus caused significant changes in parenchymal blood flow pulsatility. The inverse relationship between the ICP and CBF amplitude suggests that the changes did not occur via modification of the intracranial Windkessel mechanism. Thus, the effects likely occurred in the low-pressure vessels, i.e., capillaries and/or venules, rather than the high-pressure arteries. Future MRI studies are however required to map and quantify the effects on global cerebral blood flow.
KW - cardiac-gated inflatable device
KW - cerebral blood flow
KW - experimental model
KW - intracranial pressure
KW - intracranial pulsatility
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U2 - 10.1152/japplphysiol.00401.2022
DO - 10.1152/japplphysiol.00401.2022
M3 - Article
C2 - 36548513
AN - SCOPUS:85147047719
SN - 8750-7587
VL - 134
SP - 242
EP - 252
JO - Journal of applied physiology
JF - Journal of applied physiology
IS - 2
ER -