Natural course of perihemorrhagic edema after intracerebral hemorrhage.

ABSTRACT

BACKGROUND AND PURPOSE: There is only limited knowledge on the time course of perihemorrhagic edema (PHE) after intracerebral hemorrhage (ICH). We aimed to investigate the chronological PHE course and its relation to in-hospital mortality in a large retrospective ICH cohort. METHODS: Patients with supratentorial ICH treated at our institution between 2006 and 2009, who had received at least 3 CT scans in the course of conservative treatment, were included in the present analysis. PHE at Days 1, 2, 3, 4 to 6, 7 to 11, 12 to 16, 17 to 21, and >22 was assessed using a threshold based semiautomatic volumetric algorithm. A chart review was performed to achieve data on duration of stay, ventilation, treatment with external ventricular drains, and in-hospital mortality. RESULTS: Two hundred nineteen patients aged 69.9±10.5 years with deep (n=103) or lobar (n=116) ICH were included in the study. Mean ICH volume was 35.7±31.5 mL. Mean absolute PHE volume significantly increased from initially 32.6±29.9 mL to 63.7±46.7 mL at Days 7 to 11. No significant changes were observed at later time points. ICH volume was strongly correlated with absolute PHE volume (ρ=0.8, P<0.001) and inversely correlated with relative PHE (ρ=-0.4 to -0.5, P<0.001). Increase in absolute PHE between Days 1 and 3 was significantly predictive for in-hospital mortality (P=0.014, ExpB=1.04). CONCLUSIONS: PHE develops early after ICH and doubles within the first 7 to 11 days after the initial bleeding event. This additional mass effect may contribute to secondary clinical deterioration and mortality, especially in larger ICH. Because of its inverse correlation with ICH volume, relative PHE may not be suitable for analyses considering the clinical impact of PHE.