Method of computer nonlinear analysis and its importance for diagnosis

Computer nonlinear analysis (NLS) as a dynamic noninvasive informative method is being used more and more widely to examine the state of health affected by pathologies of different origin. NLS can be applied both in vivo (to get an NLS-spectrum of one or another part of an organ or tissue) and in vitro (to get an NLS-spectrum of extracts from tissues, biological fluids or cells); anyway, quite frequently both approaches can be combined for more accurate data interpretation.

The proceedings of the International Congresses of medical doctors (in 2000 and 2001) which dealt with new methods of diagnosis are indicative of a growing number of NLS- investigations for the purpose of diagnosing - in 2000 16 investigations were reported to have been carried out while in 2001 there were reported twice as many of them.

S.D. Tutin et al. informed about the possibility of using NLS to diagnose abscesses in the encephalon. With an abscess in the encephalon the NLS-spectrum during the biochemical homeostasis evaluation proved to detect signals from lactate and amino acids which disappeared in the course of treatment. The NLS data in vivo correlated well with the results of abscess sample tests made by means of MRC with a high resolution in vitro. Using the NLS- method one can trace the dynamics of metabolic change in the encephalon in treating epilepsy. Some data are available which indicate that it is possible to register a decline in oxidative phosphorylation in the muscles of the lower limbs with constricted vessels caused by arteriosclerosis. In the course of treatment the muscle metabolism appears to improve.

Another trend in the application of the NLS- method is its use to detect metabolic disturbance of phosphorergic compounds with muscular atrophy related to a pathology in the musculoskeletal system. Some inviting prospects for myocardial infarction diagnosis by means of the NLS- method were described by B. Kim et al. who studied exchange in the myocardium. With myocardial infarction its level was shown to decrease. The NLS-analysis method was used 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.

Moreover, NLS is reported to be used to diagnose CNS disorders, cardiovascular diseases, muscular system disorders, prostate tumors, mammary gland tumors and in addition to monitor radiation- and medicamentous therapies. The researchers demonstrated the diagnostic importance of NLS for arteriosclerosis, apoplexy, encephalomyelitis and vasculitis. NLS enables to estimate the stage of a pathology and activity of a nidus, determine a relationship between genetic characteristics, clinical symptoms and metabolic deviations in the encephalon. NLS helps to differentiate between benign and malignant tumors in the prostate by means of NLS showed that the method enabled to identify a budding change in the gland tissue and pick out the appropriate therapy in good time. K.A. Kvasov et al. presented some data about diagnosing prostate diseases (histologically confirmed benign hypertrophy and Aden carcinoma among them) by combining NLS and dynamic MRT with artificial "Magnevist" contrasting. According to the results, this kind of combination enables to specify the nature of a prostate pathology and substantially increases the diagnostic accuracy.

Special attention has been focused of late on the study of liver metabolism by means of NLS as a result of a growing number of transplantations of the organ (in Europe the annual number of liver transplantations is around 2000 and in the USA it is 10000) and as necessitated by a noninvasive evaluation of the liver function in the course of implantation. The results indicate that it is expedient to use in these cases the NLS-analysis as the ATF level in the liver represents an integral picture of cell homeostasis. There is a close correlation between the disturbed metabolisms of phosphorergic compounds and the extent of liver decompensation. Besides being used for diagnosing liver disorders in vivo, NLS makes it possible to judge the state of the transplanted liver in vitro by getting the spectral characteristics of the organ's metazodes. This is based on a good correlation between the pathological liver metabolism revealed by means of NLS and the disease prognosis. The authors emphasize that NLS enables not only to reveal pathological change in the liver but also to carry out monitoring of biochemical responses to the treatment.

Summing up what has been said one can conclude that the expanding use of NLS-analysis, including its combination with MRT with contrast intensification involved, in different fields of clinical medicine increases the efficiency and the diagnostic accuracy and is indicative of continual progress in the field of internal organ imaging techniques based on the NLS-analysis phenomenon.