Islet cell hyperplasia:It appeared oval and nodular prominence in shape with maximal diameter 1 5cm,equal signal on T 1WI and T 2WI,and no clear border between the tumor and normal pancreas tissue. It was missed by B US.

• (2 )胰岛素细胞增生 :呈卵圆形结节状外突 ；最大径为 1.；5 cm；呈等 T1 等 T2 信号；与胰腺分界不清；B超未检出病灶。