title: Poor correlation between perihematomal MRI hyperintensity and brain swelling after intracerebral hemorrhage.
abstract: OBJECTIVE
  The perihematomal hyperintensity (PHH) is commonly interpreted to represent cerebral edema following intracerebral hemorrhage (ICH), but the accuracy of this interpretation is unknown. We therefore investigated the relationship between the changes in PHH and the changes in hemispheric brain volume as a measure of edema during the first week after ICH.
  
  
  METHODS
  Fifteen individuals aged 66 ± 13 with baseline hematoma size of 13.1 ml (range 3-43) were prospectively studied with sequential MRI 1.0 ± 0.5, 2.6 ± 0.9, and 6.5 ± 1.0 days after spontaneous supratentorial ICH. Changes in hemispheric brain volume were assessed on MPRAGE using the Brain-Boundary Shift Integral (BBSI). Hematoma and PHH volumes were measured on T2-weighted images.
  
  
  RESULTS
  Brain volume increased a small but statistically significant amount (6.3 ± 8.0 ml, 0.6 ± 0.7%) between the first and second scans relative to 10 normal controls (-0.9 ± 4.1 ml, P = 0.02) and returned toward baseline at the third scan (1.5 ± 9.5 ml vs. controls 0.9 ± 4.0 ml, P = 0.85). There were no significant differences in the volume changes between the two hemispheres at scan 2 or scan 3. At both scan 2 (P = 0.04) and scan 3 (P = 0.004), the change in PHH was significantly greater than and poorly correlated with the change in ipsilateral hemispheric volume. There were no significant correlations between the change in NIH Stroke Scale (NIHSS) and the change in PHH, ipsilateral, or total brain volume at scan 2 or scan 3 (all P > 0.05).
  
  
  CONCLUSIONS
  In patients with small-to-moderate-sized hematomas, change in PHH was a poor measure of brain edema in the first week following ICH. A small degree of bihemispheric brain swelling occurred, but was of little clinical significance.
authors: Department of Neurology and Neurological Surgery, Washington University School of Medicine, 660 S. Euclid Avenue, Campus Box 8111, St. Louis, MO 63110, USA. zazuliaa@neuro.wustl.edu
authors: Allyson R
authors: AR
authors: Zazulia
authors: Tom O
authors: TO
authors: Videen
authors: Michael N
authors: MN
authors: Diringer
authors: William J
authors: WJ
authors: Powers
mesh_terms: D000328:Adult; D001929:Brain Edema / Q000175:diagnosis* / Q000503:physiopathology; D002543:Cerebral Hemorrhage / Q000175:diagnosis* / Q000503:physiopathology; D016638:Critical Illness; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D015600:Glasgow Coma Scale; D006406:Hematoma / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009929:Organ Size / Q000502:physiology; D012016:Reference Values; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed