Brain susceptibility weighted imaging signal changes in acute hemorrhagic anemia: an experimental study using a rabbit model

The aim of this study was to investigate susceptibility-weighted imaging (SWI) signal changes in different brain regions in a rabbit model of acute hemorrhagic anemia. Ten New Zealand white rabbits were used for construction of the model of acute hemorrhagic anemia. Signal intensities of SWI images of the bilateral frontal cortex, frontal white matter, temporal lobe, and thalamic nuclei were measured. In addition, the cerebral gray-white contrast and venous structures of the SWI images were evaluated by an experienced physician. Repeated bloodletting was associated with significant reductions in red blood cell count, hemoglobin concentration, hematocrit, pH, and PaCO2, and elevations of blood lactate and PaO2. In normal status, the SWI signal intensity was significantly higher in the frontal cortex than in the frontal white matter (63.10±22.82 vs. 52.50±20.29; P