- BACKGROUND AND PURPOSE: The presence of computed tomography dense signs in acute ischemic stroke indicates thrombosis. We sought to ascertain whether reversibility of these signs provides additional prognostic information. METHODS: Baseline and follow-up imaging was obtained from 18 patients who had received intravenous abciximab and heparin as part of an ongoing safety study in acute ischemic stroke. Presence of signs and their reversal were assessed and correlated with mortality and 90-day outcome. RESULTS: Fourteen of the 18 patients had dense dot signs in the middle cerebral or dense signals in the basilar artery on baseline computed tomography. The signs reversed in 7 (group 1) and persisted in 7 (group 2). Mean baseline National Institutes of Health Stroke Scale did not differ. All 7 in group 1 were alive at 90 days, with 3 of 7 alive in group 2. Ninety-day modified Rankin Scale was lower in group 1 (1.9+/-1.57) compared with group 2 (4.6+/-1.9; P=0.01). CONCLUSIONS: The reversal of dense signs predicts a much better outcome than its persistence. These signs should receive additional attention for both their diagnostic and prognostic importance.