Purpose Flow diverters (FD) is a new approach to the endovascular treatment of intracranial aneurysms which uses a high density mesh stent to induce sac thrombosis. These devices have been designed for the treatment of complex shaped and large size aneurysms. So far published safety and efficacy data on this approach is limited. We report our 2-year experience with FD in the treatment of cerebral aneurysms.
Materials and Methods From September 2008 to December 2010, 111 aneurysms (100/111 anterior circulation, 11/111 posterior circulation) were treated at our institution with FD (Silk; Balt, Montmorency, France and Pipeline; EV3, Irvine, California, USA). A total of 147 FD were implanted (1–8 per aneurysm, mean: 1.3). Modes of presentation were fortuitous (52.3%, 58/111), angiographic recurrence of previously treated aneurysms (27.0%, 30/111), compressive symptoms (18.0%, 20/111), SAH (2.7%, 3/111). Aneurysms were treated with FD alone in 57.7% (64/111) and with FD and coils in 42.3% (47/111).
Results All procedures were carried out on flat panel detector angiographic suites allowing 3D reconstruction of both aneurysm and parent vessels (Allura; Philips, Best, The Netherlands). Precise parent vessel measurements allowed choosing precisely the desired FD in order to conform to aneurysm neck and vessel geometries. 111 aneurysms (103/111, 92.8% saccular; 8/111, 7.2% fusiform; sizes 1.2 to 80, mean: 12.9 mm) were treated in 97 patients (71 women, 26 men, age ranging from 10 to 85, mean: 52 years) in 101 procedures. All patients were premedicated with dual antiplatelet therapy at least for 5 days prior to treatment. Antiplatelet activity assessment was performed in all cases (VerifiNow; Accumerics, San Diego, California, USA) Access site complications (hematomas) were noted in 5.9% (6/101, 3 requiring blood transfusions). Transient or reversible (<7 days) neurological complications (8 ischemic, 2 hemorrhagic) were noted in 9.9% (10/101). Permanent neurological complications were deplored in 7.9% (8/101). 30 days post-procedural mortality was 4.0% (4/101; 1 ischemic stroke, 1 mesencephalic compression, 1 pulmonary infection, 1 cardiac failure). To date, relief or improvement of compressive symptoms was achieved in 20.0% (4/20). No aneurysms bled or rebled after treatment. Aneurysms treated with FD alone were slightly smaller than those treated with FD and coils (mean size: 12.4 and 13.6 mm respectively; p=0.0362, Unpaired t test with Welch correction). Immediate angiographic occlusion was achieved in 15.6% (10/64) with FD alone, in 29.8% (14/47) with FD and coils. 66 (59.5%) aneurysms had been followed (mean: 9 months). At follow-up, 71.0% (27/38) of aneurysms treated with FD, while 96.4% (27/28) of aneurysms treated with FD and coils were totally occluded (Fisher's Exact Test, p=0.0094). There was no angiographic recurrence of initially totally occluded aneurysms.
Conclusions FD allow the treatment of aneurysm that were not previously amenable to selective treatment. The combination of FD and coils provide better rates of aneurysm occlusion at follow-up than FD alone, with no aneurysm recurrence.