1986 - Daniel S.J. Choy invented and performed the first PLDD (PERCUTANEOUS LASER DISC DECOMPRESSION) at the Neurosurgical Center at the University of Graz, Austria together with Prof. Peter Ascher (Director of the Department of Neurosurgery at the University of Graz, Austria).
2002 - Dr. Daniel was invited to the International Meeting “LASERFLORENCE” in Florence to teach the technique. His assistant student was a fully trained neurosurgeon Dr. Gian Paolo Tassi, from Grottammare (Italy). The hosts in Florence were ill prepared, and Dr. Tassi and Dr. Daniel spent the morning gathering the necessary equipment from several departments. Despite these difficulties they performed PLDD on two patients that afternoon in two hours, filmed by the Italian TV networks. During that time more than 150 telephone calls came in from all of Italy.
2002, 2004 and 2006 - Dr. Daniel trained Dr. Gian Paolo Tassi in doing PLDD (lumbar, dorsal and cervical) at the Laser Spine Center in New York City (Dr. Daniel was the founder and the Director of the Laser Spine Center)