Mass effect and death from severe acute stroke.

Background: In severe acute stroke, the degree of midline cerebral displacement is related to level of consciousness but not to survival. Early identification of patients at high risk of death from mass effect would assist patient management decisions.

Methods: We measured lesion volume, horizontal pineal displacement (PD), and horizontal septum pellucidum displacement (SD) on axial CT of consecutive patients with severe (Canadian Neurological Scale score < or = 5) acute hemispheric stroke. We correlated CT measurements with the probability of 14-day survival.

Results: Forty-six (39%) of 118 patients died within 14 days and 72 (61%) died within 1 year following stroke. Crude risk factors for 14-day mortality were as follows: lesion volume > or = 400 ml, SD > or = 9 mm, PD > or = 4 mm, intraventricular hemorrhage, and coma on admission. Only SD (p = 0.001) and coma on admission (p = 0.019) remained significant in multivariate analysis, but PD was highly correlated with SD (r = 0.82). PD of > or = 4 mm on a scan performed within 48 hours of stroke onset identified patients with a low probability of 14-day survival (0.16; CI 0 to 0.32) with a specificity of 89% and a sensitivity of 46%.

Conclusions: The degree of horizontal midline cerebral displacement correlates with the likelihood of death following stroke. Patients with > or = 4 mm PD on CT performed within 48 hours of stroke onset are at high risk for early death.