ABDOMINAL DIFFUSION MAPPING WITH USE OF A WHOLE-BODY ECHO-PLANAR SYSTEM

PURPOSE: To measure apparent diffusion coefficients (ADCs) of water in liver, spleen, kidney, and muscle. MATERIALS AND METHODS: Ten volunte ers (seven women and three men, aged 19-31 years [mean, 24 years]) and nine patients (five women and four men, aged 49-70 years [mean, 62 ye ars]) (liver cyst, n = 3; liver hemangioma, n = 3; liver cirrhosis, n = 2; hepatocellular carcinoma, n = 1; and liver metastasis, n = 1) und erwent magnetic resonance (MR) imaging. A stimulated-echo acquisition mode (STEAM)-type excitation and echo-planar imaging(EPI)readout was u sed in a 1.5-T echo-planar MR imaging system. RESULTS: ADCs measured i n volunteers were liver, 1.39 x 10(-3) mm(2)/sec +/- 0.16; spleen, 0.9 5 x 10(-3) mm(2)/sec +/- 0.15; muscle, 1.99 x 10(-3) mm(2)/sec +/- 0.1 6; and kidney, 3.54 x 10(-3) mm(2)/sec +/- 0.47 (mean +/- standard dev iation). Distinctive ADC values were found in organs with abnormalitie s. ADCs in patients with hepatic disease included liver cysts, 3.9-5.3 ; liver hemangiomas, 2.0-2.8; liver metastases from an islet cell tumo r, 1.2; hepatocellular carcinoma, 1.7; and liver cirrhosis, 0.9-1.2 x 10(-3) mm(2)/sec. CONCLUSION: In vivo diffusion measurements of abdomi nal organs obtained with MR imaging may prove helpful in the identific ation and classification of abdominal disease.