Reduced and standard field-of-view diffusion weighted imaging in patients with rectal cancer at 3 T—Comparison of image quality and apparent diffusion coefficient measurements. Issue 131 (October 2020)

• Record Type: Journal Article
• Authors: Attenberger, U.I.; Tavakoli, A.; Stocker, D.; Stieb, S.; Riesterer, O.; Turina, M.; Schoenberg, S.O.; Pilz, L.; Reiner, C.S.
• Is Part Of: European journal of radiology. Issue 131(2020)
• Publication Date: 2020-10
• Subjects: Diffusion weighted MRI -- DWI -- ADC -- Rectal cancer -- Zoomed DWI; Medical radiology -- Periodicals; Radiology -- Periodicals; Radiologie médicale -- Périodiques; Medical radiology; Periodicals; 616.075705
• DOI: 10.1016/j.ejrad.2020.109257
• Languages: English
• ISSNs: 0720-048X

Abstract

Abstract: Purpose: To compare a zoomed EPI-DWI (z-EPI) with a standard EPI-DWI (s-EPI) in the primary diagnostics of rectal cancer and assess its potential of reduced image artifacts. Method: 22 therapy-naïve patients with rectal cancer underwent rectal MRI at a 3 T-system. The protocols consisted of a z-EPI DWI and s-EPI DWI sequence. Images were assessed by two independent and experienced readers regarding overall image quality and artifacts on a 5-point Likert scale, as well as overall sequence preference. In a lesion-based analysis, tumor and lymph node detection were rated on a 4-point Likert scale. Apparent diffusion coefficient (ADC) measurements were performed. Results: Overall Image quality score for z-EPI and s-EPI showed no statistically significant differences (p = 0.80/0.54, reader 1/2) with a median score of 4 ("good" image quality) for both sequences. The image quality preference rank for z-EPI and s-EPI was given the category 'no preference' in 64 % (reader 1) and 50 % (reader 2). Most artifact-related scores (susceptibility, motion and distortion) did not show reproducible significant differences between z-EPI and s-EPI. The two sequences exhibited comparable, mostly good and excellent quality scores for tumor and lymph node detection (p = 0.19−0.99). ADC values were significantly lower for z-EPI than for s-EPI (p = 0.001/0.002, reader 1/2) with good agreement of ADC measurements between both readers. Conclusion: Our data showed comparable image quality and lesion detection for the z-EPI and the s-EPI sequence in MRI of rectal cancer, whereas the mean ADC of the tumor was significantly lower in z-EPI compared to s-EPI.