Initial and Long-Term Outcomes of Complex Bifurcation Aneurysms Treated by Y-Stent-Assisted Coiling with Low-Profile Braided Stents

Procedural and follow-up angiograms of a 23-year-old male patient with unruptured bilateral ICA bifurcation aneurysms. Y-stent placement was performed as a bailout procedure after coil protrusion and consequent thrombus development following a single stent-assisted coiling treatment. A and B, Preprocedural DSA and 3D reconstructed angiograms show a wide-neck 6-mm aneurysm (arrows) located at the left ICA bifurcation. C and D, Procedural control DSA and nonsubtracted angiograms show that the aneurysm has been coiled with the assistance of a single LEO Baby stent extending from the ICA to the left anterior cerebral artery. The coil mesh (arrows) protrudes into the M1 segment of the MCA. E, A procedural DSA image reveals the development of a thrombus (arrow) in the M1 segment of the MCA. F, DSA image obtained after a bailout deployment of a second LEO Baby stent into the MCA, creating a Y-configuration with the first stent. As shown in the image, the deployment of the second stent successfully treated the coil protrusion and restored the patency of the MCA. G and H, Nonsubtracted angiography and an MIP reconstruction image of flat panel CT show the Y-stent configuration with 2 LEO Baby stents. The images clearly show that there is no constriction of the second stent (deployed into the MCA) at the intersection point of the stents. I, A 12-month follow-up DSA image shows complete occlusion of the aneurysm and the patency of the stents.