title: A Novel Brainstem Hemorrhage Model by Autologous Blood Infusion in Rat: White Matter Injury, Magnetic Resonance Imaging, and Neurobehavioral Features.
abstract: BACKGROUND
  Primary brainstem hemorrhage (BSH) has the highest mortality and morbidity as a subtype of intracerebral hemorrhage. A major limitation of BSH research is the lack of a corresponding animal model. The purpose of this study was to establish a novel rat model of BSH and to characterize the resulting brain injury, especially focusing on white matter injury.
  
  
  METHODS
  BSH was produced by stereotactically injecting autologous whole blood into the pons. Time course of hematoma resolution was observed by 7-T magnetic resonance imaging. White matter injury was evaluated in detail by multiple parameters including diffuse tensor imaging (DTI), demyelination, axonal injury, oligodendrocyte degeneration, and oligodendrocyte precursor cell proliferation. Brain water content and neurobehavior were also evaluated.
  
  
  RESULTS
  Blood infusion (30 µL) led to a stable, reproducible hematoma in the right basotegmental pons. The hematoma absorption started, became obvious, and was nearly completed at 7, 14, and 30 days, respectively. Hematoma caused obvious brain edema at 3 days. White mater injury was observed pathologically, which was in line with decreased fractional anisotropy (FA) in DTI in the pons. FA reduction was also noticed in the cerebral peduncle and medulla. Behavioral abnormality persisted for at least 14 days and neurofunction was recovered within 1 month.
  
  
  CONCLUSIONS
  This novel model can produce a stable hematoma resulting in brain edema, white matter injury, and neurofunctional deficits, which could be useful for future investigation of pathophysiological mechanisms and new treatment evaluation after BSH.
authors.affiliation: Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Chuanyuan
authors.initials: C
authors.lastname: Tao
authors.affiliation: Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Ruzhi
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Hu
authors.affiliation: Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.affiliation: Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China. Electronic address: gaofabao@yahoo.com.
authors.forename: Fabao
authors.initials: F
authors.lastname: Gao
authors.affiliation: Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China. Electronic address: tcy106@163.com.
authors.forename: Chao
authors.initials: C
authors.lastname: You
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D001804:Blood Transfusion, Autologous; D001929:Brain Edema / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology / Q000523:psychology; D056324:Diffusion Tensor Imaging; D004195:Disease Models, Animal; D006406:Hematoma / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology / Q000523:psychology; D020300:Intracranial Hemorrhages / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology / Q000523:psychology; D056784:Leukoencephalopathies / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology / Q000523:psychology; D008279:Magnetic Resonance Imaging; D008297:Male; D011149:Pons / Q000098:blood supply* / Q000473:pathology / Q000503:physiopathology; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D066127:White Matter / Q000473:pathology* / Q000503:physiopathology
keywords: Brainstem hemorrhage; animal model; autologous blood injection; white matter injury