1 Singapore Health Services, 31 Third Hospital Ave, #03-03 Bowyer Block C, Singapore 168753, Singapore. Electronic address: shichengzhou94@gmail.com.
2 Department of Diagnostic Radiology, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore.
3 Department of Diagnostic Radiology, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore. Electronic address: druei@yahoo.com.