1. Effect of flow modification on aneurysm induced mass effect Szikora I *, Berentei Zs *, Kulcsar Zs *, Marosfoi M *, Gubucz I *, Nelson PK **, Berez A *** National Institute of Neurosciences Budapest, Hungary

2. Conflict of interest I. Szikora: –Coordinating investigator in PITA study –PI in PITA II. (Budapest) study –Investigator in PUFS study –Consultant to ev3. P. K. Nelson: –Consultant to ev3 A. Berez: –Founder and CEO of Chestnut Medical Inc.

3. Background The efficacy of intrasaccular - endovascular treatment in eliminating aneurysm induced mass effect has been limited (except parent vessel occlusion) direct surgery of large and giant aneurysms is efficient but carries high morbidity

4. Purpose To evaluate the efficacy of endovascular flow diversion in eliminating: –Radiologically demonstrated mass effect –Clinical signs and symptoms related to compression effect of such aneurysms

5. Patient material Indication Mass effect Incidental Headaches Mass effect by imaging Cranial nerve deficits Previous SAH Recana- lized 1329231955 75 aneurysms in 64 patients treated with the Pipeline flow diverter

6. Aneurysm characteristics Aneurysm locationAneurysm size Caver- nous Paroph- thalmic Sup. hypo- physeal PComBA Giant (>25mm) Large (10- 25mm) Small (<10mm) 1538127294125 ICA 75 aneurysms in 64 patients diameterNeck 13.8mm7.6mm

7. Follow up: angiography Complete occlusion Neck remnant Residual filling No of AN treated 75 No of AN passed 6 months 56 6 months f/u AG 53 (2 died) 50(94%)1(2%)2(4%) 12 months f/u AG 16 15(94%)1(6%)0

8. Radiological mass effect No of aneurysms with mass effect No of aneurysms with f/u MRI (3-12 months) Complete resolution of mass effect Residual mass effect 232220 (91%)*2 (9%)** *Resolution of mass effect 100% in completely occluded aneurysms **1 aneurysm partial occlusion, 1 aneurysm previously coiled

9. Before treatment 6 months 2 years

10. Cranial nerve deficits: optic nerve Aneurysms with optic nerve compression Aneurysms with N.I. compression > 3 months f/u Mean visual acuityVisual acuity before treatment 3 -6 months impro ved normal unchan ged 860,30,7131* *incomplete aneurysm occlusion

11. Before treatment: Visual acuity: 0.1 6 months: visual acuity: 1.0

12. Cranial nerve deficits: eye movements No Impro- ved normal unchanged VI-th nerve palsy 10280 III-d nerve palsy 9270 11 patients had double vision

13. Before: Double vision, III. and VI. nerve palsy 6 months: No double vision III. Improved VI. Normal

14. Conclusion Flow diverter treatment is highly effective in eliminating –Radiological mass effect –Related cranial nerve symptoms Complete aneurysm occlusion and disappearance of mass effect is needed to achieve clinical release of the clinical symptoms