1 Department of Diagnostic RadiologyTan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore.
2 Department of Otorhinolaryngology and Head and Neck, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore.
3 Department of Diagnostic RadiologyTan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore. Electronic address: [email protected].