Stretched-exponential model of DWI in differentiating malignant and benign breast lesions / 中国医学影像技术

ABSTRACT

Objective To investigate the value of stretched-exponential model of DWI in differential diagnosis of benign and malignant breast lesions.Methods Totally 58 patients with 63 breast lesions (33 benign,30 malignant lesions) were enrolled.All the patients underwent multiple b value DWI and dynamic contrast enhancement MRI (DCE-MRI) scans.The values of ADC,DDC and water molecular diffusion heterogeneity index (α) were calculated,and the time signal intensity curve (TIC) was obtained.All the parameters were compared between benign and malignant breast lesions.The diagnostic performance of different parameters was evaluated with ROC curve.Results ADC,DDC and α value of malignant lesions was (1.01±0.19)×10-3 mm2/s,(0.89±0.23)×10-3 mm2/s and 0.75±0.09,while of benign lesions was (1.41±0.27)× 10-3 mm2/s,(1.49±0.29)× 10-3mm2/s and 0.87±0.07,respectively.All 3 parameters in malignant lesions were lower than those in benign lesions (all P＜0.01).Taking 1.22 × 10-3 mm2/s as the optimal threshold,the area under the curve (AUC) of DDC was the largest as 0.958,and the corresponding diagnostic sensitivity and specificity was 96.67％ and 81.82％,respectively.AUC value was 0.976 by combining DDC with TIC,and the corresponding diagnostic sensitivity and specificity was 93.33％ and 93.94％,respectively.Conclusion The stretched-exponential model DWI can differentiate breast lesions,and diagnostic performance of combination of DDC and TIC is better than ADC or DCE.