What are the gradings of chronic pancreatitis seen on US or CT?

Normal Equivocal (either mild dilation of duct, or gland enlargement) Mild/Moderate (equivocal + >4mm dilatation or duct irregularity or cavities <10mm or parenchymal heterogeneity or focal necrosis) Severe (mild + more severe cavities/ duct dilatation/ calcification/ obstruction...)