Comparison of reduced FOV diffusion-weighted imaging of rectal cancer at 5.0T ultra-high field versus 3.0T MRI: image quality and histopathological T staging
摘要
To compare image quality (IQ) of reduced field-of-view (rFOV) diffusion-weighted imaging (DWI) for rectal cancer at 5.0T compared with 3.0T and determine whether tumor apparent diffusion coefficient (ADC) values are correlated with histopathological T staging.
Materials and methodsIn a prospective cohort, 36 patients diagnosed with rectal cancer underwent MRI scans at both 3.0T and 5.0T systems. Two experienced radiologists independently evaluated the subjective and objective IQ parameters. Objective IQ metrics were statistically analyzed using paired t-test. Subjective assessments were compared using the Wilcoxon signed-rank test. Tumor ADC values obtained at the two magnetic field strengths were further compared, and their association with histopathological T staging was examined through Spearman’s rank correlation.
ResultsObjective measures demonstrated evidently improved IQ at 5.0T rFOV DWI relative to 3.0T (all P < 0.001). Subjective evaluations confirmed superior image clarity, lesion delineation, and overall diagnostic confidence at the 5.0T platform (P < 0.001). The two systems demonstrated comparable performance with respect to image artifacts and geometric distortions, showing no meaningful statistical divergence. However, the mean tumor ADC values differed significantly between 3.0T and 5.0T imaging (P < 0.001). A notable inverse correlation was identified between ADC values and histopathological T staging at both field strengths (P < 0.001).
ConclusionrFOV DWI at 5.0T offers enhanced IQ and improved tumor visualization relative to 3.0T. The mean tumor ADC values were significantly different at 3.0T and 5.0T, which could be utilized for assessing histopathological T staging of rectal cancer.