Chun-Jung Juan1,2, Hing-Chiu Chang3, Chun-Jen Hsueh1, Hua-Shan Liu1, Cheng-Yu Chen1,2, Hsiao-Wen Chung1,4, Tzu-Chao Chuang5, Hung-Wen Kao1, Guo-Shu Huang1,2
1Radiology, Tri-Service General Hospital, Taipei, Taiwan; 2Radiology, National Defense Medical Center, Taipei, Taiwan; 3Applied Science Laboratory, GE Healthcare, Taipei, Taiwan; 4Electrical Engineering, National Taiwan University, Taipei, Taiwan; 5Electrical Engineering, National Sun Yat-sen University, Kaohsiung, Taiwan
The functionality of the parotid glands could be evaluated using diffusion-weighted imaging (DWI) noninvasively. Accurate quantification of the parotid apparent diffusion coefficient (ADC) is important not only for distinguishing pathologies but also for inter-experiment comparison. Although echo-planar DWI (EP-DWI) has been applied to measure the parotid ADC in recent decade, the results are quite discrepant due to physiological and non-physiological factors. In this study, we assessed the imaging distortion and bias in parotid ADC measurements in EP-DWI in comparison to the distortion-free technique, PROPELLER-DWI. Our results depict significant imaging distortion of EP-DWI and sequence-related biases in parotid ADC quantification.