Nō to shinkei = Brain and nerve
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A case with infarction in the territory of the anterior choroidal artery (AChA) due to embolic occlusion of the internal carotid artery (ICA) is rare. We described two cases and investigated the mechanism of the territory of the AChA. Case 1 was a 69-year-old man. ⋯ In both cases, the left carotid injection visualized the right anterior cerebral artery and right middle cerebral artery via the anterior communicating artery well, but the right AChA was not visualized. In case 1, the collateral pathways from the right external carotid artery (ECA) and the right posterior communicating artery (PCoA) to the right ICA were not supplied and the precommunicating segment of the right posterior cerebral artery was hypoplastic. In case 2, the collateral pathway from the right ECA to the right ICA was not supplied.(ABSTRACT TRUNCATED AT 250 WORDS)
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It has been considered that mannitol reduces a raised intracranial pressure effectively by improving pressure volume relationship. The objective of this study is to determine how the pressure volume status is changed by a bolus mannitol administration with using several biomechanical parameters (intracranial pressure, pressure volume index, and intracranial elastance). Our data indicated that mannitol changed the PVI more sensitively than ICP and elastance. "Estimated Intracranial Volume Change (EICVC)" has been newly defined during mannitol infusion on the basis of PVI and ICP change. ⋯ However, the temporal course of PVI indicating the intracranial venous blood pooling, can not be explained only by EICVC since the PVI has been changed more rapidly than any other parameters. Therefore, we speculated that the ratio of intracranial components could be more largely altered by mannitol than the net of intracranial volume change. The fundamental mechanism of ICP reduction by mannitol is possibly the brain water movement into venous circulation.