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Iomazenil SPECT (BZP-Receptor)

  • Jyoji Nakagawara

Abstract

123 I-Iomazenil (IMZ) [1] is a specific radioligand for the central benzodiazepine (BZ) receptor that may be useful as an indicator of cortical neuron loss after focal cerebral ischemia using SPECT [2, 3]. The reduction of BZ receptor density in reperfused cortex that remained structurally intact is likely to be the result of injury to only a limited number of neurons (i.e., incomplete brain infarction) [3]. The study of permanent or transient ischemia (lasting 3–6 h) in baboons by Sette et al. [4], who used 18 F-flumazenil as a BZ receptor ligand and PET, has a more direct relevance to the study of the incomplete brain infarction in reperfused cortex using IMZ-SPECT. They observed a decrease of BZ receptor binding not only in the infracted area but also, albeit to a lesser degree, in the CT-intact opercular cortex overlying the hypodense area. Selective neuronal necrosis with sparing of glia and microvessels is seen after transient occlusion of the MCA in macaque monkey and rats [5, 6]. The extent of ischemic neuronal damage depends on both the magnitude and duration of cerebral ischemia. In the study by Garcia et al. [7], up to 60 min of MCA occlusion followed by 7 days of survival in rats resulted in neuronal necrosis that involved isolated groups of cortical neurons (i.e., incomplete brain infarction), while no cases of cortical infarction were found. A close correlation existed between the number of necrotic neurons and the severity of the neurological deficits.

Keywords

Cortical Neuron Anterior Cingulate Cortex Moyamoya Disease Normal Database Frontal Lobe Damage 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2010

Authors and Affiliations

  1. 1.Department of NeurosurgeryNakamura Memorial HospitalChuo-kuJapan

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