1. Advances in Interventional Neuroradiology Dr James F Peerless March 2014

2. Introduction

3. Interventional Radiology Endovascular, catheter-based techniques using fluoroscopy and angiography – To diagnose and treat vascular diseases of the CNS Examples – diagnostic cerebral angiography – acute endovascular stroke treatment – revascularization of carotid and intracranial stenosis – cerebral aneurysm

4. The Past

5. From Small Beginnings Catheterisation of arterial cerebral vessels first described in 1931 by French neurologist, Dr Moniz. Access limited by size of catheters – Transfemoral and transcarotid approaches Treatment options: – Electrothrombosis (1964) – Detachable balloons (1970) – Injection into aneurysm Iron Microspheres Microcatheter developed in 1988 – Allowed direct probing of aneurysms

6. Coil Development Free coil occlusion – Detachable coils via a delivery wire – Separated with direct current – Guido Gugliemi (UCLA), 1991 Initially used in non-ruptured posterior aneurysms, poor grade SAH and those unfit for surgery Now the treatment of choice, >90% Electrolysis detachment replaced by mechanical/pressure devices

7. Coil Development

8. The Present

9. Aneurysms Coiling – Bare platinum coils – Bioactive PGA coils Increased thrombogeneity and fibrosing induction Stenting Balloon-remodelling and embolisation Flow-diverters – devices are designed to achieve aneurysm occlusion through reconstruction of the diseased segment of artery

10. Aneurysm Treatments

11. Balloon and Onyx Embolisation

12. Collected data in 2143 patients between 1994- 2002 – Clipped: 1070 (30.6 %) – Coiled: 1073 (23.7 %) Follow-up series in 2005 + 2009 conferred a survival benefit of at least seven years Increased (small) risk of rebleed Future bleeds “essentially eliminated”

13. Previous small single-centre trials showed promise of bioactive coils Bare platinum versus Cerecyte coils RCT (non-blinded), n = 500 Non-significance demonstrated, but – Increased periprocedural M&M – Poorer 6-month outcome (mRS)

14. ATENA Trial, 2010 – Data collected in 622 patients in France and Canada between 2005 & 2006 – Coiling and remodelling associated with better radiological outcomes than stenting – Factors for a favourable outcome Age < 65 Aneurysm diameter < 6 mm Dome-neck ratio > 1.5

15. Brain AVMs Embolisation techniques – nBCA n-butyl-cyano-acrylate – Onyx licensed in 2005 polymer in organic solvent Results from single-centre studies only Trade-off between long- and short-term gain – Pierot et al., 2009 (J. Neuroradiol.) >60% occlusion rates in 73% on 116 patients 2% mortality, 8% morbidity at one month Increased risk of recanalisation with reduced occlusion Periprocedural morbidity – 12.2%: Hauck et al., 2009 (Am. J Neuroradiol.) – 19.5%: Panagiotopolous et al., 2009 (Am. J Neuroradiol.)

16. The Future

17. Future Advances Aneurysms – Problems are the same as in the past Tricky aneurysms are large with wide necks Difficult to treat with high recurrence rates – flow diverters – Bettering the understanding of: aneurysm formation, growth, and rupture AVMs – New embolisation materials

18. Reference Schumacher M, Weber J. Aneurysm Treatment – a Neuroradiologic Success Story. Clinical Neuroradiology, 2008;4:203-215 Gounis J, De Leo III M, Wakhloo A. Advances in Interventional Neuroradiology. Stroke, 2010;41:e81-e87 Chen M. Interventional Neurology – Recent Advances & New Applications. US Neurology, 2011;7(1):37-40