Soon Chai Low1, Ai Huey Tan1, Shen-Yang Lim2. 1. From the Division of Neurology (S.C.L., A.H.T., S.-Y.L.) and The Mah Pooi Soo & Tan Chin Nam Center for Parkinson's & Related Disorders (A.H.T., S.-Y.L.), University of Malaya, Kuala Lumpur. 2. From the Division of Neurology (S.C.L., A.H.T., S.-Y.L.) and The Mah Pooi Soo & Tan Chin Nam Center for Parkinson's & Related Disorders (A.H.T., S.-Y.L.), University of Malaya, Kuala Lumpur. limshenyang@ymail.com.