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Supplement Scientific Posters Neuroradiology (2006) 48 (Suppl 2): 136–190 SCIENTIFICSUPPLEMENT POSTERS Carotid artery disease P2 P1 EVALUATION OF CAROTID ARTERY STENOSIS: SPIRAL CT ANGIOGRAPHY AND MAGNETIC-RESONANCE AN- MANAGEMENT OF RADIATION-INDUCED CAROTID GIOGRAPHY IN COMPARISON WITH DIGITAL SUBTRAC- STENOSIS TION ANGIOGRAPHY. ESNR ESNR A. Afaq1, G. Rajeswaran2; A.M. Turkin, I.V. Evgrafov, T.V. Mel’nikova-Pitskhelauri, 1The Catherine Lewis Cancer Centre. The Hammersmith Hospitals V.N. Kornienko; Burdenko Neurosurgery Institute, Moscow/RU NHS Trust, Imperial College L, London/GB, 2Chelsea & Westminster Hospital, London/GB PURPOSE Duplex scanning is known to be the screening method in detection PURPOSE of carotid artery (CA) stenosis, but it is pure in quantitative To review the imaging findings and management of patients with stenosis evaluation. Digital subtraction angiography (DSA) is the radiation-induced extracranial carotid artery stenosis (RICS). gold standard both in detection and evaluation of CA stenosis, but Symptomatic RICS was first described over three decades ago. It it is invasive technique and don’t provide the opportunity to study has a similar association with cerebral ischaemia and infarction as the structure of plaques. Advanced abilities of spiral CT atherosclerotic carotid stenosis. Only case reports and small angiography (CTA) and MR angiography (MRA) seems to be studies have been reported analysing the optimal management of prospect in evaluation of stenotic processes of CA and also the this condition. structure of atherosclerotic plaques. The aim of this work is the MATERIAL AND METHODS comparative analysis of CTA, MRA and DSA in evaluation of A Medline search and analysis was carried out on all English stenotic processes of CA, structure of atherosclerotic plaques. language articles on the investigation and management of RICS. Additionally, conditions of cerebral hemodynamic functioning RESULTS were evaluated using CT perfusion imaging in cases with severe It is difficult to distinguish between atherosclerotic and RICS on stenosis (>70%). histologic and angiographic criteria. However, on ultrasound, non- MATERIAL AND METHODS calcified plaques and intraplaque hypoechoic foci may be more 42 patients with symptoms of CA stenosis were selected with duplex frequent in post-radiation plaques. Management options include scanning as screening method. Stenosis was located in bifurcation carotid endarterectomy, carotid angioplasty and stenting. Endar- area in 36 patients. All patients underwent CTA (300 mAs, 120 rV, terectomy can be difficult in RICS, due to adhesions, fibrosis of collimation 6×0.5) and MRA (2DTOF, TR/TE=45/5,FA=50). 8 pts the arterial wall and tissue planes and the often extensive with severe stenosis (more, then 70%), candidates for endarteriaec- distribution of disease. Published reports over the past 10 years tomia, were selected for DSA. Percents of stenosis were calculated on have shown with increasingly larger subject numbers that carotid axial CT and MR projection with NASCET criteria. Perfusion CT angioplasty and stenting is a safe and feasible method to approach (80 kV, 200 mA, 50 slices per 50 seconds) were completed before RICS. and after surgery. Cerebral Blood Volume (CBV), cerebral Blood CONCLUSION Flow (CBF) and Mean Transit Time (MTT) were used for evaluation In the rapidly evolving area of endovascular management of of tissue henodynamics. carotid stenosis, post-radiation stenoses deserve special consider- RESULTS ation, in view of the challenge they pose to conventional surgery. In patients with stenosis of 70% and more CTA in comparison with The few, small sized studies are difficult to compare directly in and DSA showed sensitivity of 96% and specifty of 87%. Sensitivity view of differences in design and length of follow up but do show and specifity of MRA in patients with hemodynamically significant low rates of complications and restenosis where angioplasty and stenosis was 92% and 78%, respectfully. In six cases stenosis was stenting is used. overestimated by MRA. CTA was used for evaluation of plaques density. Plaques with density less then 50 HU were interpreted as “soft”, with density, ranging between 50–130 HU - as “fibrotic”,with the densities more than 130 HU - as “calcified”. Results of Neuroradiology (2006) 48 (Suppl 2): 136–190 137 postoperative CT perfusion demonstrated some shortening of MTT patient (3.8%) who had bilateral stent implantation. There was no and increasing in CBF in six cases. fatality in early or late period. CONCLUSION CONCLUSION High degree of correlation DSA results with both of CTA and CAS is less invasive than surgery and CAS under cerebral MRA data was revealed. CTA was considered to be preferable protection is a safe and effective method. Use of cerebral protective method of stenosis evaluation. CTA was useful also in evaluation devices decreases the occurence of possible complications. of plaques.structure. Duplex scanning data was gained by CTA, this techniques being used together are sufficient for the selection P4 of the candidates for surgery and treatment planning. SUCCESSFUL TRANSARTERIAL AND TRANSVENOUS P3 EMBOLIZATION OF PERSISTENT PRIMITIVE TRIGEMINAL ARTERY-CAVERNOUS SINUS FISTULA WITH DETACHABLE CAROTID ARTERY STENTING WITH CEREBRAL COILS: CASE REPORT AND REVIEW OF LITERATURE PROTECTION ESNR ESNR S. Choi, S. Jeon, S. Yoon, Y. Lee, E. Kim, S. Juhng, B. Roh; E. Akgul1, E. Aksungur2, N. Alatay3, K. Aikimbaev3, Wonkwang University Hospital, Iksan/KR K. Bicakci4, S. Bicakci5; 1Cukurova University Balcali Hospital, Adana/TR, 2Cukurova PURPOSE University, Adana/TR, 3CUKUROVA UNI. MEDICAL FACUL- Trigeminal artery is a persistent, vascular anastomotic connec- TY, Adana/TR, 4Cukorova University Balcali Hospital, Adana/TR, tion between the cavernous internal carotid artery and the basilar 5Cukurova Univ. Balcali Hospital, Adana/TR artery. It is associated with vascular steal, aneurysmal formation, vascular rupture, subarachnoid hemorrhage, and arteriovenous PURPOSE fistula. We report a case of a carotid-cavernous fistula through a Carotid artery disease is a major cause of ischemic stroke. The risk persistent trigeminal artery with endovascular treatment. of stroke is directly related with degree of stenosis in patients with MATERIAL AND METHODS carotid artery disease. In this study, we evaluate safety and A 40-year-old woman presented with proptosis, conjunctival effectiveness of primary carotid artery stenting (CAS) under chemosis of the left eye, a left sixth cranial nerve palsy, and an cerebral protection. audible bruit for 4 weeks. Cerebral angiography demonstrated a left MATERIAL AND METHODS carotid-cavernous sinus fistula associated with persistent primitive Twenty-six patients admitted to hospital with clinical symptoms trigeminal artery. Endovascular treatment with Guglielmi detach- and diagnosis of carotid artery stenosis on carotid colour Doppler able coil (GDC) via transarterial and transvenous routes was planned, US, cervical MR angiography, CT angiography and DSA were because a suitable detachable balloon could not be obtained. included in this study. Stents were applied to 30 carotid artery RESULTS stenosis, 4 of which were bilateral in 26 patients. Seven (27%) of Postembolization angiography demonstrated nonfilling of the the patients were female and 19 (73%) male; mean age was 63 fistula and preservation of the internal carotid artery and persistent (54–79) years. Cerebral CT and/or MRI were done before and trigeminal artery. At 12 months follow-up, the patient had had no after procedures. Follow-up was performed by Doppler US on 2nd recurrence of audible bruit and diplopia. day, at 1st, 3rd, and 6th months and subsequently every six CONCLUSION months. Rate of stenoses was over 50%. The authors describe endovascular technique for coil embolization RESULTS of a fistula and review literature concerning persistent primitive Procedure was successful in 28 lesions. Primary stent implantation trigeminal artery-carotid sinus fistula. was done after replacing protection filter distally. Carotid artery stenting (CAS) could not be applied in one (3.3%) lesion because P5 the stenosis couldn’t be overcome. In another lesion, stent could not be opened because distal metal marking stayed on the stent SPONTANEOUS GIANT ANEURYSM OF EXTRACRANIAL while it was tried to be opened. The success of the procedure was INTERNAL CAROTID ARTERY 93.3%. Embolic material in the filter after the procedure was seen in four patients (14.2%). Procedure was complicated in 6 (20.6%) ESNR patients. Early minor neurologic complication developed in one patient (3.8%) and late minor neurologic complication developed C.G. Ramos1, C. Pereira2, J. Xavier2, A. Stocker2; in another one (3.8%). Restenosis developed after 12 months in a 1Porto/PT, 2HGSA, Porto/PT 138 Neuroradiology (2006) 48 (Suppl 2): 136–190 PURPOSE MATERIAL AND METHODS Aneurysms of the extracranial internal carotid artery (ICA) are CTA has been performed in 58 patients within a week prior and rare. They can be caused by a wide variety of conditions, the most after carotid artery stenting for procedure planning and control of common of all being atherosclerosis. Other causes include trauma, the interventional result. Scanning range covered the aortic arch, fibromuscular dysplasia, infection, auto-immune connective tissue whole carotid artery as well as the intracranial circulation for disorder or arterial dissection. Clinically, they can be asymptom- planning of optimal projection angles for the intervention, primary
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