[Differential diagnostic signs of metastases to the mediastinal lymph nodes in rats with a transplanted Walker tumor].

Density of contrast-free and contrasted mediastinal lymph nodes was studied in simulated chronic pneumonia and lung cancer using the DED-3 type digital computer in combination with the REIS-D X-ray source. Direct high (over 80 times) X-ray magnification may be used to measure lymph node density using digital print-out. This, in turn, may be employed for mathematical analysis and development of differential algorithm for computer. In cases of involvement, the higher mean density of contrast-free lymph nodes was matched by the lower one in contrasted lymph nodes, as compared with normal lymph nodes and those in chronic inflammation. Different values of lymph node tissue heterogeneity (A) and that of mean density of lymph nodes (B3) may be used to find differential algorithm for computer diagnosis of metastasis.