[1] Agcy Sci Technol & Res, Biomed Imaging Lab, Singapore 138671, Singapore
[2] Natl Univ Singapore, Dept Elect & Comp Engn, Singapore 117548, Singapore
[3] Natl Univ Singapore, Div Bioengn, Singapore 117548, Singapore
[4] Natl Univ Singapore, Dept Prevent Dent, Singapore 117548, Singapore
[5] NUS Grad Sch Integrat Sci & Engn, Singapore, Singapore
[6] Natl Univ Singapore, Dept Diagnost Radiol, Singapore 117548, Singapore
[7] Natl Univ Singapore, Dept Diagnost Imaging, Singapore 117548, Singapore