V.D. Artyukh, U.A. Shovkoplyas, A.A. Gavrilov Computer-based non-linear analysis (NLS) as a dynamic non-invasive informative method is increasingly used to examine the status of health affected by pathologies of different origin. NLS can be applied both in vivo (to acquire an NLS-spectrum of one or another part of an organ or tissue), and in vitro (to obtain an NLS-spectrum of extracts from tissues, biological fluids or cells). Often both approaches can be combined for a more accurate data interpretation. The usage of NLS at a clinic requires devices producing an at least 20-30mT eddy magnetic field. The proceedings of the latest International Congress of Medical Doctors (2000 and 2001), that dealt with new methods of diagnosis, provides evidence of a growing number of NLS-investigations used for the diagnostic purposes - the 2000 summit heard 16 presentations on the subject, while in 2001 there were twice as many. S.D. Tutin et al. reported on the possibility of using NLS to diagnose abscesses in the encephaloa. It appears that the presence of an abscess in the encephalon in the NLSspectrum generates evaluation some signals from lactate and amino acids which can be detected using the biochemical homeostasis aspect of the program. These signals disappear in the course of treatment. The NLS data in vivo correlates well with the results of abscess sample tests made by means of MRC with a high resolution in vitro. Using the NLS-method the dynamics of metabolic change in the encephalon when treating epilepsy can be traced. Some data are available, that indicate a possibility to register a decline in oxidative phosphorylation in the lower limbs muscles with construction of the vessels caused by ante-riosclerosis. In the course of treatment the muscle metabolism appears to improve. Another trend in the application of the NLS method is detection of metabolic disturbance of phosphoregic compounds at muscular atrophy related to a pathology in the musculoskeletal system. Some promising prospects for myocardial infarction diagnosis by means of the NLS method were described by U.A. Shovkopylas et al., who studied the ATP exchange in the myocardium. At a myocardial infarction its level was proven to decrease. The NLSanalysis method was employed to study the dynamics of change in the metabolism of lipids in the liver affected by cirrhosis. The NLS-investigation of the pancreas affected by malignant degeneration enables to diagnose tumor progression, judge of the efficiency of radiation- or chemotherapy and also adjust individual dosage schemes for inoperable patients. 8Moreover, NLS use has been reported in the diagnosis of CNS disorders, cardiovascular diseases, muscular system disorders, prostate tumors, mammary gland tumors and in addition to monitor radiation and medicinal therapies. Researchers have demonstrated the diagnostic importance of NLS for arteriosclerosis, apoplexy, encephalomycitis and vasculitis. NLS permits an estimate of the phase of a pathology and activity of the nidus (focus), determining a relationship between genetic characteristics, clinical symptoms and metabolic deviation in the encephalon. NLS helps to differentiate between benign and malignant tumors in the mammary gland. The studies of abnormal changes in the prostate gland by means of NLS showed that the method allowed identification of an incipient change in the gland tissue, thus enabling appropriate therapy selection. K.A. Kvasov et. al. presented some data about diagnose of prostate diseases (including histologically confirmed benign hypertrophy and Aden carcinoma) by combining NLS and dynamic MRT with artificial “Magnevist” contrasting. According to the derived results, this kind of combination enables definition of the pattern of a prostate pathology and substantially increases the diagnostic accuracy. Recently special attention has been focused on a study of the metabolism by means of NLS, necessitated by a growing number of organ transplants (in Europe the annual number of liver transplantations is around 2000 and in the USA it is 10000) due to this method’s noninvasive evaluation of the liver function in the course of implantation. The results indicate appropriateness of using the NLS-analysis in these cases since the ATP level in the liver mirrors an integrated picture of cell homeostasis. There is a close correlation between the disturbed metabolisms of phosphorergic compounds and the extent of liver de-compensation. Beyond diagnosing liver disorders in vivo, NLS facilitates a view on the state of the transplanted liver in vitro by acquiring special characteristics of the organ’s metazodes. This is based on a good correlation between the pathological liver metabolism defined by means of NLS and the disease prognosis. The authors would like to emphasize that NLS enables not only definition of pathological change in the liver but also monitoring of the biochemical responses to treatment. In summary it can be concluded that the ever growing use of NLS-analysis in different fields of clinical medicine, including its combination with MRT with contrast amplification involved, increases the efficiency and diagnostic accuracy and is indicative of a continuous progress in the field of internal organ visualization techniques based on the NLS-analysis phenomenon.