THE EXPERIENCE OF THE CONTRASTING OF PERIPHERAL NERVES STRUCTURES FOR APPLIED ANATOMICAL RESEARCHES

Applied anatomical studies of the structure and topography of peripheral nerves and experimental surgical interventions on them using laboratory animals are an important stage in the development of new and improvement of existing methods of reconstructive microsurgery of the peripheral nervous system. The aim of this work was to find effective methods for contrasting the structure of peripheral nerves for precision morphological studies and topographic and anatomical substantiation of intra-truncal reconstructive interventions on the nerves. On the anatomical material, which included 18 by usual formaldehyde techniques fixed upper limbs of human corpses and 10 non-fixed corpses of laboratory rabbits, methods of contrasting the main structures of the nerve trunks were tested. The key techniques were the sub-perineural and sub-epineural injection of a photocontrast mixture and the installation of an X-ray contrast marker in the nerve trunk to study the features of the nerve trunk skeletotopy at different levels in an integral block of tissues without preparation. The developed method allowed expanding the possibilities of precision topographic and anatomical studies and qualitatively improving the demonstrativeness of preparations. The best results of injection of individual perineural sheaths were observed when using non-fixed anatomical material. On fixed and weakly fixed material, injections of a tinting composition under the external epineurium contributed to an increase in the quality of anatomical research methods, which is especially important when studying the intrastem microtopography of the nerve trunk bundles. The introduction of the thinnest metal conductor into the nerves through the opened perineural bundle with subsequent x-ray examination of preparations, based on our experience, is a technically feasible and demonstrative method for studying the topography of the nerve trunks, including methods for assessing the degree of their displacement at various positions of the limb segments. Thus, the developed method for contrasting peripheral nervous structures expand the possibilities of applied morphological studies of their intrastem topography, and the use of non-fixed anatomical material makes it possible to perform contrasting of individual perineural sheaths with liquid formulations.

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