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Author Yang, L. ♦ Son, JB ♦ Ma, J. ♦ Hazle, J. ♦ Carter, BW ♦ Lin, S. ♦ Cheng, S.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword APPLIED LIFE SCIENCES ♦ RADIATION PROTECTION AND DOSIMETRY ♦ BIOLOGICAL MARKERS ♦ BIOMEDICAL RADIOGRAPHY ♦ ESOPHAGUS ♦ IMAGES ♦ MUSCLES ♦ NEOPLASMS ♦ NMR IMAGING ♦ PATIENTS ♦ SURGERY
Abstract Purpose: We investigated whether quantitative diffusion imaging can be used as an imaging biomarker for early prediction of treatment response of esophageal cancer. Methods: Eight patients with esophageal cancer underwent a baseline and an interim MRI studies during chemoradiation on a 3T whole body MRI scanner with an 8-channel torso phased array coil. Each MRI study contained two axial diffusion-weighted imaging (DWI) series with a conventional DWI sequence and a reduced field-of-view DWI sequence (FOCUS) of varying b-values. ADC maps with two b-values were computed from conventional DWI images using a mono-exponential model. For each of DWI sequences, separate ADCall was computed by fitting the signal intensity of images with all the b-values to a single exponential model. For the FOCUS sequence, a bi-exponential model was used to extract perfusion and diffusion coefficients (ADCperf and ADCdiff) and their contributions to the signal decay. A board-certified radiologist contoured the tumor region and mean ADC values and standard deviations of tumor and muscle ROIs were recorded from different ADC maps. Results: Our results showed that (1) the magnitude of ADCs from the same ROIs by the different analysis methods can be substantially different. (2) For a given method, the change between the baseline and interim muscle ADCs was relatively small (≤10%). In contrast, the change between the baseline and interim tumor ADCs was substantially larger, with the change in ADCdiff by FOCUS DWI showing the largest percentage change of 73.2%. (3) The range of the relative change of a specific parameter for different patients was also different. Conclusion: Presently, we do not have the final pathological confirmation of the treatment response for all the patients. However, for a few patients whose surgical specimen is available, the quantitative ADC changes have been found to be useful as a potential predictor for treatment response.
ISSN 00942405
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-06-15
Publisher Place United States
Journal Medical Physics
Volume Number 42
Issue Number 6


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