Stepwise multiparametric MR imaging for sinonasal diseases. Stepwise multiparametric MR imaging effectively differentiated between benign (A and B) and malignant (C) sinonasal diseases. A, Benign lesions included 3 organized hematomas, 1 fungal rhinosinusitis, 1 inflammatory polyp, and 1 rhinosinusitis (type 1 area, 45 ± 19%; overall ADC, 1.20 ± 0.41 × 10−3 mm2/s; extremely low + low ADC, 53 ± 24%). B, Benign lesions included 4 rhinosinusitis, 3 inverted papillomas, 3 inflammatory polyps, 2 fungal rhinosinusitis, 2 hemangiomas, and 1 angiofibroma (type 1 area, 4 ± 6%; overall ADC, 1.57 ± 0.22 × 10−3 mm2/s; extremely low + low ADC, 21 ± 17%). C, Malignant tumors included 10 SCCs, 5 lymphomas, 2 undifferentiated carcinoma, 2 adenoid cystic carcinomas, 1 melanoma, 1 rhabdomyosarcoma, 1 olfactory neuroblastoma, and 1 metastatic renal cell carcinoma (type 1 area, 4 ± 7%; overall ADC, 0.83 ± 0.26 × 10−3 mm2/s; extremely low + low ADC, 86 ± 16%).