Motion pictures of the blood flow of the inner ear were taken through the round window membrane in guinea pigs. Blood vessels of the inner ear which could be observed through the round window membrane were mainly the vein of the round window (VRW) and its branches. These blood vessels could be observed without an operation on the inner ear. As the VRW encloses the round window at the side of the scala tympani, the round window was histologically sectioned to know the three-dimensional relation of the VRW to the round. window membrane. Moreover the round window was dissected to observe the blood vessels on the round window membrane using hematoxylin-eosin staining.
