Cerebral hemodynamics and histological changes following acute cerebral venous occlusion in cats

Using an acute cerebral venous occlusion model prepared by injecting cyanoacrylate into the cerebral venous system, superior sagittal sinus pressure (SSSP) and regional cerebral blood flow (r-CBF) were measured. In the same model, changes in cerebral metabolism at the site of r-CBF measurement were observed using magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). Cases were classified according to occlusion site: group SSS [occlusion of the superior sagittal sinus (SSS) only], group LS[occlusion of SSS plus lateral sinus (LS)] and group CV[SSS and LS plus cortical veins (CV)]. In groups SSS and LS, SSSP changed very little up to 6 hours after occlusion. In group LS, r-CBF decreased slightly, but the change was not significant. In contrast, an increase in SSSP and decrease in r-CBF were observed in group CV. Phosphorus MRS also demonstrated a decrease in phosphocreatinine (PCr) and adenosine triphosphate (ATP) and increase in inorganic phosphorus (Pi) following occlusion. Histopathological examination of group CV revealed dramatic changes, including the development of intracerebral hematoma and edema. Experimental application of the proposed model revealed that widespread occlusion of the sinuses can cause an increase in intravenous pressure with a concomitant decrease in r-CBF, resulting in metabolic complications such as a decrease in PCr and ATP and an increase in Pi.