例1:患者男,64岁。1994年1月起出现多饮、多食及体重减轻。空腹血糖14.1mmol/L,诊断为“糖尿病”口服降糖药治疗。1994年5月CT检查发现胰头部占位性病变,CT增强显示:胰头部低密度肿块4.8cm×3.9cm,紧靠下腔静脉。B超检查胰头结构反射不清,后下方见一4.6cm×3.9cm的不均回声区, Example 1: Patient male, 64 years old. Since January 1994, there have been more drinks, more food, and weight loss. Fasting blood glucose 14.1 mmol/L, diagnosed as “diabetic” oral hypoglycemic agents. In May of 1994, CT examination revealed pancreatic head space-occupying lesions. CT enhancement showed that the low-density mass of the head of the pancreas was 4.8 cm × 3.9 cm, and was adjacent to the inferior vena cava. B-ultrasonography of the pancreatic head structure was unclear, with a 4.6cm x 3.9cm inhomogeneous echo area seen at the bottom.