Tissue characterization of head and neck lesions using diffusion-weighted MR imaging with SPLICE

Abstract

Purpose The purpose of this study was to evaluate the usefulness of diffusion-weighted (DW) MR imaging with split acquisition of fast spin-echo signals (SPLICE) in the tissue characterization of head and neck mass lesions. Patients and methods DW MR images of 67 head and neck mass lesions were obtained using SPLICE with b-factors of 0 and 771 s/mm 2. The lesions were classified into three categories: 16 cysts, 32 benign tumors, and 19 malignant tumors. After ADC maps were constructed for all lesions, ADC values were calculated and compared among the three categories. Results No case showed severe image distortion on DW MR imaging with SPLICE, and reliable ADC maps and ADC values were obtained in all cases. The mean ADC value of cysts was 2.41 ± 0.48 × 10 −3 mm 2/s, which was significantly higher than that of benign (1.48 ± 0.62 × 10 −3 mm 2/s) and malignant (1.23 ± 0.45 × 10 −3 mm 2/s) tumors ( P < 0.001). However, there was no significant difference between the ADC values of benign and malignant tumors ( P = 0.246). When an ADC value of 2.10 × 10 −3 mm 2/s or higher was used as the diagnostic criterion for cysts, the sensitivity, specificity, and accuracy were 94%, 88%, and 90%, respectively. Conclusion SPLICE was considered a recommended DW MR imaging technique for the head and neck. Although ADC values were useful in differentiating cysts from tumors, they contributed little in predicting malignancy.