Diffusion-weighted MR Imaging Of The Breast At 3.0T:the Diagnosis Efficiency Of Multi-parameters

Objective To investigate the diagnosis efficiency of the decline rate of signal intensity and apparent diffusion coefficient with different b values to differentiate benign and malignant breast lesions. Methods Totally 254 patients 269 breast lesions(148 malignant lesions and 121 benign lesions) confirmed by histopathology underwent 3.0T diffusion-weighted magnetic resonance imaging. Four/Five b-values (Os/mm2,400s/mm2,800s/mm2,1000s/mm2/Os/mm2,400s/mm2, 800s/mm2,1200s/mm2,1600s/mm2 are applied. The signal intensity and ADC values of the breast lesions are measured respectively. The signal intensity decline rate(SIDR) and apparent diffusion coefficient decline rate (ADCDR) are calculated, respectively. SIDR= (SIlow-SIhigh)/SIlow, the Show represents the signal intensity of lesions with low b value, and the SIhigh represents the signal intensity of lesions with high b value; ADCDR=(ADClow-ADChigh)/ADCiow, the ADClow represents the ADC value of lesions with low b value, and the ADChigh represents the ADC value of lesions with high b value. The independent-samples t-test is used for statistical analyses and the receiver operating characteristic(ROC) curve is used to evaluate the diagnosis efficiency of the SIDR, ADC value and ADCDR value. Results 1. The SIDR of malignant breast lesions is significant lower than that of benign breast lesions with b-value combinations of 0s/mm2-400s/mm2,400s/mm2-800s/mm2, 800s/mm2-1200s/mm2, and 1200s/mm2-1600s/mm2.2. The sensitivities of SIDR to differentiate benign and malignant breast lesions are 82.5%,84.1%,84.1% and 77.8%, the specificities are 84.1%,88.6%,86.4% and 86.4%, the diagnosis accordance rates are 83.2%,86.0%,85.0% and 81.3%, the PPV are 88.1%,91.4%,89.8% and 89.1%, the NPV are 77.1%,79.6%,79.2% and 73.1% respectively with the. four b-value combinations.3. The ADC value of malignant breast lesions are significant lower than that of benign breast lesions with b-values of 400s/mm2,800s/mm2,1000s/mm2, 1200s/mm2 and 1600s/mm2.4. The sensitivities of ADC value to differentiate benign and malignant breast lesions are 72.0%,75.5%,70.6%,84.1% and 84.1%, the specificities ware 86.0%,88.4%,80.5%,90.9% and 90.9%, the diagnosis accordance rates are 78.4%,81.4%,75.3%,86.9% and 86.9%, the PPV are 85.8%,88.5%,80.0%, 93.0% and 93.0%, the NPV are 72.2%,75.4%,71.3%,80.0% and 80.0% respectively with the five b-values.5. The ADCDR of malignant breast lesions are significant higher than that of benign breast lesions with b-value combinations of 400s/mm2-800s/mm2 and 800s/mm2-1200s/mm2, however no significant difference is observed in ADCDR between benign and malignant breast lesions with b-value combination of 1200s/mm2-1600s/mm2.6. The sensitivities of ADCDR to differentiate benign and malignant breast lesions are 66.7% and 77.8%, the specificities are 70.5% and 70.5%, the diagnosis accordance rates are 68.2% and 74.8%, the PPV are 76.4% and 79.0%, the NPV are 59.6% and 68.9% respectively with 400s/mm2-800s/mm2 and 800s/mm2-1200s/mm2 b-value combinations.7. DWI is useful for the differential diagnosis of breast lesions with b-values of 800s/mm2, 1000s/mm2 and 1200s/mm2.Conclusion The ADC value, the decline rate of signal intensity and ADC value with different b-values can be used to differentiate benign and malignant breast lesions, and the diagnosis efficiency with b-value of 800s/mm2,1000s/mm2, and 1200s/mm2 are applicable.