title: Natural history of perihematomal edema after intracerebral hemorrhage measured by serial magnetic resonance imaging.
abstract: OBJECTIVE
  knowledge on the natural history and clinical impact of perihematomal edema (PHE) associated with intracerebral hemorrhage is limited. We aimed to define the time course, predictors, and clinical significance of PHE measured by serial magnetic resonance imaging.
  
  
  METHODS
  patients with primary supratentorial intracerebral hemorrhage ≥ 5 cm(3) underwent serial MRIs at prespecified intervals during the first month. Hematoma (H(v)) and PHE (E(v)) volumes were measured on fluid-attenuated inversion recovery images. Relative PHE was defined as E(v)/H(v). Neurologic assessments were performed at admission and with each MRI. Barthel Index, modified Rankin scale, and extended Glasgow Outcome scale scores were assigned at 3 months.
  
  
  RESULTS
  twenty-seven patients with 88 MRIs were prospectively included. Median H(v) and E(v) on the first MRI were 39 and 46 cm(3), respectively. Median peak absolute E(v) was 88 cm(3). Larger hematomas produced a larger absolute E(v) (r(2)=0.6) and a smaller relative PHE (r(2)=0.7). Edema volume growth was fastest in the first 2 days but continued until 12 ± 3 days. In multivariate analysis, a higher admission hematocrit was associated with a greater delay in peak PHE (P=0.06). Higher admission partial thromboplastin time was associated with higher peak rPHE (P=0.02). Edema volume growth was correlated with a decline in neurologic status at 48 hours (81 vs 43 cm(3), P=0.03) but not with 3-month functional outcome.
  
  
  CONCLUSIONS
  PHE volume measured by MRI increases most rapidly in the first 2 days after symptom onset and peaks toward the end of the second week. The timing and magnitude of PHE volume are associated with hematologic factors. Its clinical significance deserves further study.
authors.affiliation: Stanford Care program, Stanford University Medical Center, Cali., USA. chitrav@stanford.edu
authors.forename: Chitra
authors.initials: C
authors.lastname: Venkatasubramanian
authors.forename: Michael
authors.initials: M
authors.lastname: Mlynash
authors.forename: Anna
authors.initials: A
authors.lastname: Finley-Caulfield
authors.forename: Irina
authors.initials: I
authors.lastname: Eyngorn
authors.forename: Rajalakshmi
authors.initials: R
authors.lastname: Kalimuthu
authors.forename: R W
authors.initials: RW
authors.lastname: Snider
authors.forename: Christine Anne
authors.initials: CA
authors.lastname: Wijman
mesh_terms: D000368:Aged; D001929:Brain Edema / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D002543:Cerebral Hemorrhage / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography