Magnetic resonance imaging and magnetic resonance cholangiopancreatography findings compared with fecal elastase 1 measurement for the diagnosis of chronic pancreatitis.

ABSTRACT

OBJECTIVES: To correlate magnetic resonance cholangiopancreatography (MRCP) and magnetic resonance imaging (MRI) findings of the pancreas with the pancreatic exocrine function determined by fecal elastase 1 concentration. METHODS: Magnetic resonance imaging and MRCP findings of 81 consecutive patients with clinically suspected chronic pancreatitis and 21 healthy volunteers were evaluated. All subjects underwent MRI/MRCP and fecal elastase 1 testing within 1 to 4 weeks' interval. Magnetic resonance cholangiopancreatography images were evaluated according to Cambridge classification. Magnetic resonance imaging of the pancreas was assessed for pancreatic size, signal, and arterial enhancement. RESULTS: All volunteers had normal fecal elastase 1 levels (>200 microg/g) and normal MRI/MRCP findings. Thirty-one of 56 patients revealed MRI and/or MRCP findings despite normal fecal elastase 1 concentration. Four of 25 patients revealed normal MRI and MRCP findings despite low fecal elastase 1 concentration (<200 microg/g). Magnetic resonance imaging findings of size (P = 0.00001), arterial enhancement (P = 0.00001), and parenchymal signal (P = 0.001) were significantly different among the control group, patients with normal fecal elastase 1 levels, and patients with low fecal elastase 1 levels. Magnetic resonance cholangiopancreatography findings (P = 0.00001), pancreatic size (P = 0.00001), arterial enhancement (P = 0.014), and parenchymal signal (P = 0.004) on MRI correlated with the fecal elastase 1 concentration. CONCLUSIONS: Magnetic resonance imaging/MRCP findings correlate with fecal elastase 1 concentration and may precede pancreatic exocrine insufficiency in the early stages of chronic pancreatitis.