Morphometric indexes and computerized diagnosis of gastric dysplasia

In general, the diagnosis and grading of dysplasia of the gastric mucosa depends upon the pathologist's experience. The authors suggest N/C, P1/D1, P2/D2, R/R and NCI as 5 morphometric indexes and objective criteria in diagnosis and grading of this lesion. N/C involves the ratio of nuclei to cytoplasm; P1/D1 is the ratio of the dysplastic tubule perimeter to the diameter of its equivalent circle (obtained by transformation of the irregular perimeter); P2/D2 is the ratio of perimeter obtained by tracing the edges of nuclei bordering the lumen of the dysplastic tube to the diameter of the equivalent circle; R/R is the ratio of P1/D1 to P2/D2, which remains almost constant in spite of the fact that P values of tubules cutting through normal branches may increase in cases without atypia. For this reason, R/R may be regarded as an index for estimating the reasonability of the sampling. NCI is the ratio of nuclear perimeter to the diameter of its equivalent circle. In accordance with the above indexes, the diagnosis and grading of dysplasia can be assigned by computer analysis.