Fig.9. Carotid angiogram (A, B): a large aneurysm of the left PCoA-PCA (Case 4). Control superselective angiogram after subtotal occlusion of the aneurysm with coils (C). Control angiogram after the LEO stent implantation (D, E, F): preserved patency of the left PCoA-PCA. Control carotid angiogram a day after operation: thrombosis of the left PCoA-PCA at the stent level (G, H, I). Retrograde filling of P3-5 branches through cortical anastomoses with a region of the left MCA (J): there is no neurologic deficit.