Is the age of the Cerebral Bypass Gone?,Jonathan White, M.D.Associate Professor of Neurosurgery UT Southwestern Medical Center Dallas, Texas,Historical Indications For Bypass:,Vascular replacement: Complex aneurysms Tumors Ischemia Moya Moya disease Atherosclerosis,Historical use of bypass?,Fukushima 1986-2006 100 patients, Saphenous vein Aneurysm, Menigioma, carotid body, glomus, other Three types of bypass Petrous to paraclinoid Cervical external to petrous Cervical external to M2,Things Change,Traditional ways no longer needed:,Better Technology?,Tumors:,Better microsurgery Microscope Ultrasonic aspirator,Tumors: Gamma Knife,Aneurysms?,Better microscope Better clips Intra-operative angiography Anesthesia Better surgeons? Better surgical training,Aneurysms: Coils and Stents,What about Ischemia?,Results of Bypass Studies: Bypass does not work,N Engl J Med. 313 (19):1191-2000, 1985, Nov 7.714 Medical and 663 STA-MCA bypass patients Followed 56 months No difference overall between groups Some surgical subgroup did worse: MCA stenosis, carotid occlusion with TIA,Angioplasty and Stent,Does new technology and information eliminate the need for traditional techniques?,Gamma Knife?,Gamma knife results,Poor control with large volume tumors Risk of vascular injury,Aneurysm Coiling?,UT Southwestern 2002-200695 aneurysms greater then 2.0 CM 17 were treated by primary endovascularOnly 9 (53%) completely occluded12 (71%) required re-treatment,Ischemic disease: Flaws of previous bypass trials,Pre operative strokes considered surgical failure Selection bias good surgical candidates not randomized Medical failure cases did not cross Not enough power to identify subgroups which may benefit from bypass,Ischemia: Need to measure at risk tissue,Yonas, J NSG 1993 Xe CT; compared 5% vs 50% drop in flow with diamox 68 patients for 24 months 4.4% vs 36% stroke risk in low flow Pts Grubb, JAMA 1998 PET evidence of high oxygen extraction, 31 month 11/39 (28%) vs 2/42 (5%) ipislateral stroke risk,STA-MCA bypass for ischemia:,STA-MCA bypass,STA-MCA bypass,STA-MCA bypass,STA-MCA Bypass,STA-MCA results,Japanese EC-IC Bypass trial (JET) 1st 206 patients, surgery group has significantly fewer strokes Stanford study of Moya Moya patients Decreased future risk of stroke Regression of Moya Moya collaterals Coss trial High risk group randomized,Traditional techniques still have role.,Carotid replacement Complex aneurysm Skull based tumor Ischemic disease Measure blood flow to find at risk tissue Select proper patients,Concluding Case:,Combined Techniques,Combined techniques,Combined Techniques,Combine past and future,