ROLE OF CT ANGIOGRAPHY IN PATIENT SELECTION FOR THROMBOLYTIC THERAPY IN ACUTE HEMISPHERIC STROKE

Background and Purpose-It has been shown that thrombolytic therapy can improve clinical outcome in a subgroup of patients with acute cerebra l ischemia, This subgroup was characterized by certain clinical and im aging findings leg, moderate to severe neurological deficit for less t han 3 to 6 hours, occlusion of the middle cerebral artery, lack of ext ended infarct signs on CT, and efficient leptomeningeal collaterals). Although not part of published prospective randomized rtPA trials, inf ormation about the status of the brain vessels would be helpful in the selection of patients who may benefit the most. Our purpose was to de termine the feasibility of CT angiography (CTA) in patients with acute hemispheric ischemia and to evaluate its relevance for thrombolytic t herapy. Methods-CTA was performed in 40 consecutive patients (11 women and 29 men; age range, 19 to 80 years) with moderate or severe sympto ms (National Institutes of Health Stroke Scale score of greater than o r equal to 8) of acute hemispheric ischemia. CTA findings were compare d with Doppler ultrasonography (US; n=22) and intra-arterial digital s ubtraction angiography (DSA; n=7). Twenty patients received thrombolyt ic therapy, the remaining patients received intravenous heparin, Resul ts-Images and 3-dimensional reconstructions of diagnostic quality coul d be obtained in all patients. Thirty-four patients had a vessel occlu sion. The extent of leptomeningeal collaterals correlated significantl y with the outcome after thrombolytic therapy (r(s)=0.46, P<0.05), The evaluation of diagnostic accuracy showed a high agreement with US (22 of 22) and DSA (6 of 7). Conclusions-CTA can provide important inform ation for the initiation of therapy in patients with acute hemispheric ischemia, Identification of patients with autolyzed thrombi, occlusio n of the internal carotid artery bifurcation, and poor leptomeningeal collaterals is feasible with the use of CTA. These patients may have l ittle potential for benefit from thrombolytic therapy.