Reperfusion-associated hemorrhagic transformation in SHR rats: Evidence of symptomatic parenchymal hematoma

Erica C. Henning, Lawrence L. Latour, John M. Hallenbeck, Steven Warach

Research output: Contribution to journalArticlepeer-review

25 Scopus citations


Background and Purpose: Symptomatic hemorrhagic transformation (HT) is the most important complicating factor after treatment with intravenous tissue plasminogen activator. In this study, we used multimodal magnetic resonance imaging to investigate the incidence and severity of reperfusion-based HT in spontaneously hypertensive rats after ischemia/reperfusion. Methods: Twenty male spontaneously hypertensive rats were subjected to 30 minutes of middle cerebral artery occlusion via the suture model. Diffusion-weighted, T2-weighted, and gradient-echo imaging were performed on days 1, 2, 3, 4, and 7 for longitudinal evaluation of lesion evolution, vasogenic edema, and HT, respectively. Findings on gradient-echo images were classified according to the severity of hemorrhage: no HT; punctate or small petechial hemorrhage (HI-1); confluent petechial hemorrhage (HI-2); hematoma with absent/mild space-occupying effect (PH-1, ≤30% lesion volume); and hematoma with significant space-occupying effect and potential perihematomal edema (PH-2, >30% lesion volume). Histopathologic evaluation of HT was performed after final imaging for comparison with magnetic resonance imaging results. Results: Final hemorrhage scores based on severity were as follows: HI-1 23.1%, HI-2 30.8%, PH-1 30.8%, and PH-2 15.4%. Similar to clinical observations, only PH-2 was associated with neurologic deterioration and associated weight loss. Conclusions: This model has a high incidence of parenchymal hematomas (46.2%) and therefore is appropriate for the evaluation of novel therapeutics targeting blood-brain barrier integrity and the reduction of symptomatic HT events (PH-2), as well as those potentially "at risk" for neurologic deterioration (PH-1).

Original languageEnglish (US)
Pages (from-to)3405-3410
Number of pages6
Issue number12
StatePublished - Dec 1 2008


  • Hemorrhagic transformation
  • Middle cerebral artery occlusion
  • Parenchymal hematoma
  • Reperfusion
  • Spontaneously hypertensive rats
  • Stroke

ASJC Scopus subject areas

  • Clinical Neurology
  • Cardiology and Cardiovascular Medicine
  • Advanced and Specialized Nursing


Dive into the research topics of 'Reperfusion-associated hemorrhagic transformation in SHR rats: Evidence of symptomatic parenchymal hematoma'. Together they form a unique fingerprint.

Cite this