Intracranial stenting

Levy El, Siddiqui AH, Crumlish A et al. First Food and Drug Administration-approved prospective trial of primary intracranial stenting for acute stroke SARIS (stent-assisted recanaMzation in acute ischemic stroke). Stroke. 2009 40 3552-3556... 

Benndorf G, Klucznik RP, Strother CM (2006) Angiographic computed tomography for imaging of underdeployed intracranial stent. Circulation 114 499-500... 

Stenting of an acutely occluded intracranial vessel may provide fast recanalization by entrapping the thrombus between the stent and the vessel wall. A recent study in which 19 patients with acute occlusions at the ICA terminus n = 8), M1/M2 (n = 7), or basilar artery (n = 4) were treated with balloon-expandable stents showed a TIMI 2 and 3 recanalization rate of 79% and no symptomatic intracranial hemorrhages (Fig. 4.5). ... 

Self-expanding stents with a higher radial force (e.g., WingSpan, Boston Scientific Corp.) will probably play a key role in acute stroke cases related to intracranial atherosclerotic disease. Antegrade flow is essential for the maintenance of vascular patency, as particularly evident in patients with severe proximal stenoses who commonly develop rethrombosis after vessel recanalization. Furthermore, stenting of the proximal vessels may be required in order to gain access to the intracranial thrombus with other mechanical devices or catheters. In a recent series, 23 of 25 patients (92%) with acute n = 15) or subacute n = 10) ICA occlusions were successfully revascularized with this technique. " ... 

Levy El, Ecker RD, Horowitz MB, Gupta R, Hanel RA, Sauvageau E, Jovin TG, Guterman LR, Hopkins LN. Stent-assisted intracranial recanalization for acute stroke early results. Neurosurgery 2006 58 458-463 [discussion 458 63]. 

Henkes H, Miloslavski E, Lowens S, Reinartz J, Liebig T, Kuhne D. Treatment of intracranial atherosclerotic stenoses with balloon dilatation and self-expanding stent deployment (WingSpan). Neuroradiology 2005 47 222-228. 

Lylyk R Cohen JE, Ceratto R, Eerrario A, Miranda C. Angioplasty and stent placement in intracranial atherosclerotic stenoses and dissections. AJNR Am J Neuroradiol 2002 23 430 36. 

Initial tests in the rat revealed a high degree of tissue compatibility of Dat-Tyr-Hex derived polymers. More detailed tests are now in progress. In addition, tyrosine derived polymers are currently being evaluated in the formulation of an intracranial controlled release device for the release of dopamine, in the design of an intraarterial stent (to prevent the restenosis of coronary arteries after balloon angioplasty), and in the development of orthopedic implants. The use of tyrosine derived polymers in these applications will provide additional data on the biocompatibility of these polymers. 

Higgins JN, Owler BK, Cousins C, Pickard JD (2002) Venous sinus stenting for refractory benign intracranial hypertension. Lancet 359 228-230... 

Bypass or endarterectomy of proximal vertebral artery stenosis Release of the vertebral artery from compressive fibrous bands or osteophytes Extracranial-to-intracranial procedures to bypass vertebral artery stenosis or occlusion Angioplasty and stenting of the vertebral and basilar arteries... 

The use of intracranial angioplasty and stenting is strongly supported in the few institutions where the technology exists. Whether these procedures should be attempted in patients outside clinical trials remains controversial. 

The treatment of patients with symptomatic intracranial atherosclerotic disease can be summarized into prevention of occurrence of intraluminal thrombosis, plaque stabilization, and control of risk factors for atherosclerosis. Anticoagulation (compared with aspirin) has not shown to be beneficial in patients with intracranial atherosclerotic disease [24]. Current guidelines recommend that aspirin alone, the combination of aspirin and extended release dipyridamole, and clopidogrel monotherapy (rather than oral anticoagulants) are aU acceptable options [24]. hi patients with hemodynamically sigifificant intracranial stenosis who have symptoms despite medical therapies (antithrombotics, statins, and other treatments for risk factors), the usefulness of endovascular therapy (angioplasty and/or stent placement) is uncertain and is considered investigational [22, 25],... 

Lubicz B, Leclerc X, Levivier M et al. Retractable self-expandable stent for endovascular treatment of widenecked intracranial aneurysms prehminary experience. Neurosurgery. 2006 58 451-457 discussion 451-457... 

Zaidat OO, Wolfe T, Hussain SI et al. Interventional acute ischemic stroke therapy with intracranial self-expanding stent. Stroke. 2008 39 2392-2395... 

Embolic materials for both intracranial AVMs and aneurysms have come a long way since the first endovascular embolization procedure was carried out. Much advancement to this branch of neurosurgery came about because of an emphasis on development of equipment that was better suited to endovascular techniques. Some of these inventions include flow-directed microcatheters, endovascular balloons, and re-designed stents. Owing to a greater capacity to perform endovascular techniques with suitable equipment, the development of better embolic materials has followed. Now, there are a variety of techniques and materials that endovascular neurosurgeons have at their disposal, all of which provide a variety of benefits, yet have considerable drawbacks. Efforts are always being made to improve current materials and techniques, as well as to... 

Lanzino, G., Kanaan, Y., Perrini, P., Dayoub, H. Fraser, K. (2005) Emerging concepts in the treatment of intracranial aneurysms stents, coated coils, and liquid embolic agents. Neurosurgery, 57, 449-459. 

S Stents Designed for Intracranial Use 220 5.4.7.9 Liquid Embolic Agents 221... 

Nowadays there are several self expanding stents specifically designed for intracranial use available. These stents are extremely flexible and access through tortuous vessels is facilitated. Even distal arteries can be reached easily. Since they are not balloon mounted the risk of damaging the artery is reduced. 

Lanzino G, Wakhloo AK, Fessler RD, Hartney ML, Guter-man LR, Hopkins LN (1999b) Efficacy and current limitations of intravascular stents for intracranial internal carotid, vertebral, and basilar artery aneurysms. J Neurosurg 91 538-546... 

---