BACKGROUND AND OBJECTIVES: Cochlear blood flow is considered important as one of many causes of various inner ear diseases. Many studies have been performed to prove the decrease in cochlear blood flow as a cause of those diseases. This study was performed to determine the effects of cochlear ischemia induced by AICA occlusion on the relation of cochlear blood flow (CBF) in guinea pigs. MATERIALS AND METHODS: In 3 guinea pigs, the AICA was exposed through the basal portion of the skull with stable systemic blood pressure. The CBF of the basal area was monitored with laser Doppler flowmetry (LDF). The AICA was clamped for several minutes. With different durations, the LDF was measured under systemic blood pressure monitoring. RESULT: The vascular conductance in preocclusion state was 0.09+/-0.04 TPU (tissue perfusion unit)/mmHg. During occlusion of AICA for above 1 minute, abrupt decrease and following slow increase of CBF was observed. CONCLUSION: The autoregulation of CBF was identified, but it was incomplete even under the stable blood pressure. This study can be a good model for evalulation of hearing function during partial cochlear ischemia, but occulusion of labyrinthine artery will be a better choice for complete cochlea ischemia model.
Animals ; Arteries* ; Blood Pressure ; Blood Pressure Monitors ; Cochlea ; Guinea Pigs* ; Guinea* ; Hearing ; Homeostasis ; Ischemia ; Labyrinth Diseases ; Laser-Doppler Flowmetry ; Perfusion ; Skull