1. V ERTEBRAL ARTERY ORIFICE STENOSIS ; PTA AND S TENTING IN THE 43 PATIENTS Reza Mohamadian, MD. Neuroscience research center(NSRC) Tabriz University.

2. Bamford et al : incidence and natural history of four clinically distinct subgroups of cerebral infarction in a community-based study of 675 patients with first-ever stroke. Of 543 patients with a cerebral infarct, 129 (24%) had infarcts clearly associated with the vertebrobasilar arterial territory. Those in this group were at greater risk of a recurrent stroke later in the first year after the index event but had the best chance of a good functional outcome. Ref:Bamford JRef:Bamford J, Sandercock P, Dennis M, Burn J, Warlow C.Classification and natural history of clinically identifiable subtypes of cerebral infarction. Lancet. 1991 Jun 22;337(8756):1521-1526.Sandercock PDennis MBurn JWarlow C

3. Evidence of vertebral artery stenosis were found in 72% of patients with vertebrobasilar ischemia. Postmortem and angiographic studies showed that atherosclerotic stenosis of the vertebral artery is most frequent at the origin. Ref: 1. NA Moufarrij, JR Little, AJ Furlan, G Williams and DJ Marzewski,Vertebral artery stenosis: long-term follow-up, Stroke 1984;15;260-263. 2. George B, Laurian C. Vertebrobasilar ischaemia: its relation to stenosis and occlusion of the vertebral artery. Acta Neurochir (Wien) 1982;62:287–295

4. From October 2008 To January 2010 we prospectively enrolled consecutive patients with vertebral artery orifice stenosis who developed confirmed vertebrobasillar stroke.

5. I NCLUSION CRITERIA : 1. Angiographic evidence of more than 50% ostial stenosis in the dominant vertebral artery 2. Clinical signs and symptoms of vertebrobasilar stroke confined and confirmed by experienced stroke neurologist

6. In a vessel with the caliber of the vertebral artery, stenosis of 50% or greater is likely to be hemodynamically significant, similar to lesions in intracranial vessels. Ref : Chimowitz MI, Kokkinos J, Strong J, et al. The Warfarin-Aspirin Symptomatic Intracranial Disease Study. Neurology. 1995;45:1488-1493.

7. The stenosis severity was calculated similar to the method proposed by carotid stenosis in the North American Symptomatic Carotid Endarterectomy Trial (NASCET)and Carotid And Vertebral Artery Transluminal Angioplasty Study (CAVATAS) trial and the used formula was as the following: Percent stenosis=100 (1- A ̸ V) Where A is diameter of the residual lumen at the point of maximal stenosis and V is diameter of disease-free distal vertebral artery at the point where the walls were approximately parallel Ref: 8.Rothwell PM, Eliasziw M, Gutnikov SA, Fox AJ, Taylor DW, Mayberg MR, Warlow CP, Barnett HJM, for the Carotid Endarterectomy Trialists’ Collaboration. Analysis of pooled data from the randomized controlled trials of endarterectomy for symptomatic carotid stenosis. Lancet. 2003;361:107–116. 9.Lucy J. Coward, Dominick J.H. McCabe, Joerg Ederle, Roland L. Featherstone, Andrew Clifton, Martin M. Brown and on behalf of the CAVATAS Investigators, Long-Term Outcome After Angioplasty and Stenting for Symptomatic Vertebral Artery Stenosis Compared With Medical Treatment in the Carotid And Vertebral Artery Transluminal Angioplasty Study (CAVATAS): A Randomized Trial, Stroke 2007;38;15261530.

8. E XCLUSION CRITERIA : 1. vertebrobasilar stenotic lesion beyond the first vertebral artery segment. 2. Tandem intracranial occlusive lesions. 3. Lesions in an rudimentary vertebral artery. 4. Other potential cause of stroke, such as a cardiac source for embolism, vertebral artery dissection, vasculitis. 5. Terminally ill patient. 6. Patients were unable to give informed consent or unwilling to undergo intervention. 7. Patients with a disabling stroke.

10. Stenosis more than 50 % was considered significant and these patient underwent stenting and PTA by using of balloon mounted bare metal stent which was deployed by using 8-10 atm pressure. The goal was to achieve a residual stenosis of less than 20%, with complete lesion coverage

11. Forty three patients with confirmed symptomatic vertebral artery orifice stenosis were treated by stenting at our institute over a period 18 months.

12. Thirty patients were men (69.8%) and 13 cases were female (30.2%). Mean age :71.65+/_ 7.743 (age range 55 to 84 years). Mean degree of stenosis:70.24 +/- 6.313 Mean age (male):70.80 +/- 7.378 Mean age (female): 73.62 +/- 8.5

13. Twenty two (51.16%) patients presented with left vertebral artery stenosis, Mean degree of stenosis in this group was 72.05 +/- 11.303 percent. In the twenty one cases (48.84 %) there was right side vertebral artery stenosis, in this group mean degree of stenosis was 69.76 % +/- 9.808 percent.

14. There was evidence of internal carotid artery involvement in thirty patients(30/43, 69.6%).

15. -Two cases : bilateral carotid occlusion. -Twelve patients: bilateral internal carotid artery stenosis.(12/30,40%). - Nine patients (9/30, 30%):significant(more than- 60%) carotid artery stenosis.

20. There was no significant difference between prevalence of carotid artery stenosis in the right or left vertebral artery involvement, male or female gender except for cases with right internal and bilateral internal carotid occlusion which all were male. (five and two cases respectively).

21. There was evidence of L eft renal artery involvement in the five different cases, which in two cases there was significant stenosis and occlusion in the another one. all patients were male

24. Procedural complications: 0 % stent occlusion: one patient restenosis : one patient ( 40% and asymptomatic) Overall : less than 5 % restenosis, with at least six months follow up

28. C ONCLUSION : Unlike occlusive disease of the extracranial carotid artery, which can be diagnosed and followed up using ultrasonography, vertebral orifice stenosis is difficult to demonstrate using noninvasive testing and may require angiography for definitive diagnosis. Lack of interventional neuroradiologist and also ignoring of vertebral artery disease as the common etiology of vertebrobasilar stroke by most of neurologists could be reasons for underestimate the importance and delay in diagnosis and treatment of these patients in the our region.

29. C ONCLUSION : Poor risk factors control especially hypertension is one of the main reasons for the high incidence of coexistence atherosclerotic lesion in the other major extracranial arteries. Relatively High incidence of renal artery involvement in the patients with left vertebral artery stenosis reiterates the importance of consideration of extra cranial arterial lesions during the neurointerventional procedures.