title: Specific changes in human brain following reperfusion after cardiac arrest.
abstract: OBJECTIVE
  Very few reports are available on serial changes in human brain after cardiac arrest. The primary objective of this study is to investigate sequential neuroradiological changes in patients remaining in a persistent vegetative state following resuscitation after cardiac arrest.
  
  
  METHODS
  We repeatedly studied eight vegetative patients resuscitated from unexpected out-of-hospital cardiac arrest using computed tomographic (CT) scanning and high-field magnetic resonance (MR) imaging at 1.5 T.
  
  
  RESULTS
  In seven of the eight patients, CT scans obtained between days 2 and 6 features symmetrical low-density lesions in the bilateral caudate, lenticular, and/or thalamic nuclei. These ischemic lesions were persistently of low density on serial CT scans. In these seven patients, MR images demonstrated what were thought to be hemoglobin degradation products derived from minor hemorrhages localized in the bilateral basal ganglia, thalami, and/or substantia nigra. Diffuse brain edema in the acute stage and diffuse brain atrophy in the chronic stage were consistent neuroradiological findings. No abnormal enhanced lesions were demonstrated by CT scans.
  
  
  CONCLUSIONS
  The most characteristic findings on high-field MR images were symmetrical lesions in the bilateral basal ganglia, thalami, and/or substantia nigra with specific changes suggestive of minor hemorrhages that were not evident on CT scans. We speculate that these minor hemorrhages result from diapedesis of red blood cells in these regions during the reperfusion period through the endothelium disrupted by ischemia-reperfusion insult.
authors.affiliation: Department of Neurosurgery, Nara Medical University, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Fujioka
authors.forename: K
authors.initials: K
authors.lastname: Okuchi
authors.forename: T
authors.initials: T
authors.lastname: Sakaki
authors.forename: K
authors.initials: K
authors.lastname: Hiramatsu
authors.forename: S
authors.initials: S
authors.lastname: Miyamoto
authors.forename: S
authors.initials: S
authors.lastname: Iwasaki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001479:Basal Ganglia / Q000000981:diagnostic imaging / Q000473:pathology; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D001929:Brain Edema / Q000000981:diagnostic imaging / Q000473:pathology; D002545:Brain Ischemia / Q000000981:diagnostic imaging / Q000473:pathology; D002421:Caudate Nucleus / Q000000981:diagnostic imaging / Q000473:pathology; D003128:Coma / Q000000981:diagnostic imaging / Q000473:pathology*; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006323:Heart Arrest / Q000473:pathology / Q000628:therapy*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015424:Reperfusion; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000473:pathology; D013787:Thalamic Nuclei / Q000000981:diagnostic imaging / Q000473:pathology; D013788:Thalamus / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed