An illustration of the secretin effect with the calculated pancreatic flow rate in a 54-year-old man with chronic pancreatitis. A-E: There was a visible increase in DF at 1, 3, 5, 7, 9, 11 min after secretin, grade 3 DF was present on SMRCP at 10 min; F, G: A plot of change in volume over time from patient data, normal response with a flow rate of 6.8 mL/s and PT of 7 min.