Diffusion kurtosis imaging in diagnosis of rectal adenocarcinoma: Compared with DWI / 中国介入影像与治疗学

ABSTRACT

Objective: To analyze the application value of diffusion kurtosis imaging (DKI) in diagnosis of rectal adenocarcinoma compared with DWI. Methods: Thirty-eight patients of rectal adenocarcinoma confirmed by pathological biopsy (rectal adenocarcinoma group) and 38 healthy volunteers with matched age and gender (normal control group) were collected. MR scanning including T1WI, T2WI, DWI and DKI were performed in all subjects. ADC value, mean diffusivity (MD) and mean kurtosis (MK) value were obtained after image processing. Mann-Whitney U was used to compare parameters between the two groups. ROC was used to evaluate the diagnostic efficacy of MK, MD and ADC. Spearman correlation analysis was used to analyze the correlation between ADC and MD, MK. Results: MK in rectal adenocarcinoma group was higher than that in normal control group (P<0.001). MD and ADC in rectal adenocarcinoma group were lower than those in normal control group (P<0.001). AUC in diagnosis of rectal adenocarcinoma of MK, MD, ADC was 0.911, 0.888 and 0.827, respectively (all P<0.05). Taken 0.59, 2.15×10-3 mm/s2 and 1.35×10-3 mm/s2 as the thresholds, the sensitivity of MK, MD, ADC was 89.50%, 78.90%, 76.30%, and the specificity was 84.20%, 73.70%, 73.70%, respectively. There was negative correlation between ADC and MK (r=-0.460, P<0.05) and positive correlation between ADC and MD (r=0.994, P<0.05). Conclusion: DWI monoexponential parameters and DKI models are helpful to diagnosis of rectal adenocarcinoma. DKI can provide more information about the microenvironment with higher diagnostic efficacy.