1. Unruptured Aneurysms G Narenthiran L Alakandy J P Holland Greater Manchester Neurosciences Centre Hope Hospital Salford

2. Tools for estimating the Life-time risk of rupture & Effect of intervention on life-expectancy

3. Unruptured aneurysms Increasing numbers being diagnosed 45% - 80% of patients with ruptured aneurysm may die Not all rupture Treatment morbidity 0-16%; mortality 0- 25% Treat those at high risk of rupture

4. ISUIA 2003 Prospective Multi-centre 1692 patients did not have treatment Selection bias Not randomised Aneurysms < 2mm not included Mean duration of follow-up was 4.5 years Patients who subsequently underwent treatment excluded from analysis Included only North America and Europe

5. ISUIA, 2003 The best we have Findings of ISUIA (2003), could be incorporated into the global view of UIA Considered along with other data pertaining to the patient

6. Objective Tools for calculating rapidly at: Neurovascular MDT meetings Clinics

7. Method Cumulative risk (%) = 100 x {1- [(1-annual risk)/100]^years}

8. Maths of Probability 100 98 2 1.96 96.4 100 × 0.98 100 × 0.98 × 0.98 100 × 0.98 × 0.98 × 0.98 100 × (risk of no-rupture) years Chance of non-rupture = Chance of rupture = 100 – chance of no-rupture Annual risk of rupture = 2% Annual risk of no-rupture = 98%

9. Calculation: Simple Vs Actual SimpleActual 1% annual risk over 10 years 109.6 3 % annual risk over 20 years 6046

10. Updated ISUIA (2003) < 7 7-1213-24 ≥ 25 Group 1 Group 2 Cavernous carotid 0003%6.4% AC/MC/IC01.5%2.6%14.5%40% Post-P comm 2.5%3.4%14.5%18.4 %50% 5 year cumulative rupture rate. Wiebers DO et al. Lancet 2003; 362: 103-10

11. Annual risk of rupture of unruptured aneurysm < 7 7-1213-24>=25 Group 1 Group 2 Cavernou s carotid 0000.61.3 AC/MC/IC00.30.53.19.7 Post-P comm 0.50.73.1413

12. Risk of Intervention Vs natural history The Risk of intervention is immediate Risk of natural history is distributed over the life-time

15. Need to take into out those who will have a good outcome following rupture

16. Life table Life-expectancy tables for 2001-2003 Constructed abridged life-tables

17. Look-up tables ‘Actuarial-type’ table Gender specific Calculations performed using Microsoft ® Excel ® 2003 Table laid out using Adobe ® Illustrator CS2 ® and Adobe ® InDesign CS2 ®

18. ‘Hope’ calculator Life-time risk of rupture of unruptured aneurysms Effect of intervention on the life- expectancy Software developed with Macromedia ® Flash 8 ® Both Windows and Mac compatible

19. 55 year old male with sah with an incidental 5 mm Acomm Aneurysm

20. A 50 year old female with 8 mm rt. PICA aneurysm

21. A 45 year lady with 8 mm MCA aneurysm A 60 year male with 13 mm basilar artery aneurysm

22. Acknowledgements Mr Leggate, Mr King Mr Hutchinson, Dr Laitt Mr West, Mr Richardson, Miss Pickett, Dr Hughes, Dr Herdwardkar

23. Acknowledgements Mr Kirkpatrick, Mr Laing Professor Mendelow, Mr Mitchell Professor Harbaugh (Penn State) Professor Wiebers (Mayo Clinic) Professor Tamargo (Johns Hopkins)

25. Questions?