The value of the apparent diffusion coefficient in MR diffusion weighted imaging for the differential diagnosis of sinonasal masses / 中华放射学杂志

ABSTRACT

Objective To investigate the diagnostic value of apparent diffusion coefficient in the evaluation of sinonasal masses.Methods Sixty-seven sinonasal solid masses over 1 cm in diameter confirmed by pathology were retrospectively analyzed,all patients underwent preoperative routine MRI with DWI,the ADC values were measured in ROI within the solid mass.The patients were divided into benign and malignant groups by the histopathology,according to pathological findings,the patients were further divided into the hematolymphoid tumors,the malignancy of epithelium and mesenchymal tissue,the benign tumors of epithelial and mesenchymal tissue,and vasogenic masses.ANOVA test and t test were used to compare the ADC values of different groups.The receiver operating characteristic curve (ROC) was constructed using various cut points of ADC for different parameters to confirm the diagnostic threshold value and evaluate the diagnostic efficacy.Results All lesions were solitary.There were 22 malignant tumors,of which 6 lesions were hematolymphoid tumors and 16 lesions malignancy from epithelium and mesenchymal tissue.There were 45 benign tumors,of which 22 lesions were benign tumors from epithelium and mesenchymal tissue and 23 lesions vasogenic masses.The mean ADC value of malignant and benign masses was(0.88 ± 0.26) × 10-3 mm2/s and (1.54 ± 0.41) × 10-3 mm2/s respectively.There was statistically significant differences between them (t =6.897,P ＜ 0.01).The mean ADC value was(0.63 ± 0.10) × 10-3 mm2/s in hematolymphoid tumors,(0.97 ±0.24) × 10 3 mm2/s in malignancy from epithelium and mesenchymal tissue,(1.38 ± 0.23) × 10-3 mm2/s in benign tumors from epithelium and mesenchymal tissue,(1.68 ± 0.49) × 10-3 mm2/s in vasogenic masses respectively.There was statistically significant difference among all 4 groups(F =22.788,P ＜ 0.01),and the differences between any 2 groups were still statistically significant(P ＜ 0.05).The area under the ROC calculated was 0.945.Using an ADC value of 1.08 × 10-3 mm2/s as the threshold value for differentiating malignant from benign lesions,the best result obtained had a sensitivity of 81.8％ (18/22),specificity of 97.8％ (44/45),accuracy of 92.5 ％ (62/67).Conclusion The ADC value is a valuable tool in differentiating benign from malignant masses and different kinds of masses in sinus and nasal cavity.