Fig. 7.
This figure depicts the percent change in blood flow (black bars) and oxygenation (white bars) detected at the T4, T7, T11, and L2 to L3 vertebral levels, respectively. Clamping the proximal descending thoracic aorta cuts off blood supply from intercostal arteries, making the spinal cord flow heavily dependent on flow from vertebral arteries above the occlusion site. One would then expect a greater decrease in blood flow and oxygenation the farther one moves away from the occlusion site and vertebral artery sources. Flow and oxygenation measurements made sequentially from T4 to L3 during proximal aortic occlusion documented this pattern.