Acinarization (parenchymal blush) observed during secretin-enhanced MRCP: clinical implications

T2 hyperintensity of pancreatic acini during secretin-enhanced MRCP is called "acinarization." We sought to determine the clinical significance of this finding.

Patients were selected if the radiology report included the phrases "acin*" (where * represented a wild card search) or "blush" using the institution's customized lexicon-search software. Sixty-seven consecutive patients without acinarization on secretin-enhanced MRCP who also underwent ERCP were enrolled as the control group. The intensity of acinarization was classified into three groups: grade 0, no visible acinarization; grade 1, barely visible parenchymal hyperintensity; or grade 2, easily visible parenchymal hyperintensity. ERCP findings of ductal abnormalities and basal pancreatic sphincter manometry were recorded.

There were higher frequencies of divisum (p = 0.001) and of a clinical history of recurrent acute pancreatitis (p < 0.001) and higher basal pancreatic sphincter of Oddi manometric pressure measurements (p = 0.008) in the acinarization group. There was no difference in the frequency of ERCP-defined chronic pancreatitis (p = 0.10) between the groups. In patients with acinarization, a higher mean sphincter pressure was seen in patients with more intense acinarization than in those with faint acinarization, but this difference was not significant (p = 0.22). Ampullary tumors were found in four patients with acinarization.

Acinarization probably occurs in patients with a propensity for increased pancreatic ductal pressure (i.e., patients with divisum, elevated basal pancreatic sphincter pressure, ampullary tumor) and adequate exocrine function (absence of severe chronic pancreatitis).