Abstract #3482

Imaging Distortion and Quantification Bias of Parotid ADC Measurements in EP-DWI and Fast Spin-Echo PROPELLER-DWI

Chun-Jung Juan^1,2, Hing-Chiu Chang³, Chun-Jen Hsueh¹, Hua-Shan Liu¹, Cheng-Yu Chen^1,2, Hsiao-Wen Chung^1,4, Tzu-Chao Chuang⁵, Hung-Wen Kao¹, Guo-Shu Huang^1,2

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.