Abstract
Superselective intraarterial thrombolysis was performed in 29 of 53 consecutive patients with evolving acute cerebral infarction due to occlusion of the middle cerebral artery (MCA), while the other 24 patients were treated conservatively. Based on angiographic findings, the occlusion sites were classified into 3 types : 1) M1 proximal, occlusion at the MCA trunk proximal to the lenticulostriate arteries (thrombolysis 4/conservative treatment 15 patients) ; 2) M1 distal, occlusion at the MCA trunk distal to the lenticulostriate arteries (15/2 patients) : 3) M2-M4, occlusion after the MCA branches (10/7 patients). Successful recanalization with clinical improvement was achieved in 18 of 29 patients (62.1%). M1 distal occlusions were more likely to be recanalized successfully (11/15, 73.3%) , whereas successful thrombolysis for M1 proximal occlusion was very difficult to achieve (1/4, 25.0%) because of the difficulty in preserving the lenticulostriate arterial territories. The successful recanalization rate in patients with M2-M4 occlusions was slightly lower (6/10, 60.0%) than in those with M1 distal occlusion (11/15, 73.3%) due to technical catheterization problems. The successful recanalization rate was higher in patients with embolic occlusions (12/16, 75.0%) than in those with thrombotic occlusion (6/13, 46.2%) There was little or no difference in the rate of hemorrhagic transformation with clinical exacerbation between thrombolytically (20.7%) and conservatively (16.7%) treated groups. These results indicate that local thrombolysis for acute MCA occlusion is safe and efficacious, particularly in patients with M1 distal occlusion. The involvement of the lenticulostriate arteries is an important determinant of successful thrombolysis.
