The Quantitative Variations of the Pancreatic Islet Tissue in a Mixed Series of Cases

Ahistological survey of the pancreas in a large series of unselected cases quickly discloses the fact that the amount of islet tissue varies a great deal from case to case. Heilberg (1), and later, Ogilvie (2), devised methods for estimating the weight of an average islet and also the number of islets in a given pancreas. From these data it was possible, too, to calculate by weight, the proportion of islet tissue in the pancreas. These figures were arrived at through area readings. Ogilvie's work has been confined to the creation of normal standards, and to the age variations. In the present series, however, the chief consideration is the possible effects of disease on the amount of islet tissue present. The amount of islet tissue in each section was estimated by area readings made with a planimeter. In a number of cases readings were made on sections from several parts of the same pancreas; these readings corresponded so closely as to confirm the view that islet tissue is distributed fairly uniformly, and that readings from any one section were representative.