Former Director of Neurosurgery at Jeonju Jesus Hospital Tianjin, China Guest Professor at Jeil Central Hospital 2004 Visiting Professor at Wuui Hospital, Dalian, China 2005 Visiting Professor, Second Peoples Hospital, Shenzhen, China 2006 Visiting Professor, Center for Spinal Surgery, Shenyang Bongcheng Hospital, China 2006 Visiting Professor, Center for Spinal Surgery, Tianjin Peoples Hospital, China 2006 PLA Headquarters Guest Professor 2008 Visiting Professor, Peoples Liberation Army General Hospital, China 2009 Guest Professor, Gwangju Medical University Hospital, China 2009 Visiting Professor, Nanjing Medical University, China Visiting Professor, 2010 Visiting Professor, Zhongxin University Peoples Hospital, China 2012 Visiting Professor, Sobei Peoples Hospital, China 2012 Visiting Professor, Heochang Spine Specialty Hospital, China 2013 Visiting Professor, Guang Jiang First Peoples Hospital, China 2013 Visiting Professor, Qinghai Provincial Peoples Hospital, China Visiting Professor, Shenzhen Namsan Peoples Hospital, China 2014 Visiting Professor, Xian Seogyeong Hospital, China 2014 Visiting Professor, Korea