1. Early ventriculoperitoneal shunt surgery for the treatment of obstructive hydrocephalus caused by subarachnoid hemorrhages or intraventricular hemorrhages : Hydrocephalus 2008, Hannover, Germany

2. Aneurysm surgery based on only 3D CT angiography (CTA) without conventional angiography : 2009 Korean Society of Neurosurgeons, Cheongju,South Korea

3. Rapidly growing mycotic distal middle cerebral artery (MCA) Aneurysms in patient with bacterial endocarditis : 2009 AANS/CNS Cerebrovascular Section Meeting, San Diego, U.S.A

4. Intracranial hemorrhages in patients who is taking coumadin for the oral anticoagulation and their prothrombin time INR was less than 3.5 : 2008 AANS Annual meeting (American Association of neurological surgeons), Chicago, U.S.A.

5. Spontaneous acute subdural hematomas caused by cortical arteriole bleeding :2007 EANS European Association of Neurological Surgeons,Glasgow,Scotland,UK

6. Clinical and surgical differences between two groups of hemorrhagic stroke caused by hypertension and anticoagulant therapy : 2006 Joint world congress on stroke, Cape Town, South Africa

7. The value of camera equipped cellular phone for a neurosurgeon who is working as an only neurosurgeon in a medium sized hospital : 2006 American Association of Neurological Surgeons(AANS)Annual Meeting, San Francisco,U.S.A.