RU2379040C1 - Method for prevention of cicatricial nerve compression, traumatic peripheral paralyses and pareses - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to experimental medicine and concerns development of the methods for prevention of cicatricial nerve compression, traumatic peripheral paralyses and pareses. It is ensured by introduction of 2 ml of polymer hydrogel of carboxymethyl cellulose sodium salt to an experimental animal into within an operational nerve trauma.

EFFECT: invention allows providing effective prevention, because gel forms a barrier between nerve surfaces and surrounding tissues, that prevents growth of connective tissue and cicatricial compression of nervous fibre that in turn improves regeneration of nervous tissue and restores nerve conductivity.

1 tbl, 1 ex, 9 dwg

Description

The invention relates to medicine, in particular to neurosurgery.

Closest to the claimed solution is the method proposed by Zinatullin P.M. and Gilmanov A.Zh. (application No. 2002105074, Bashkir State Medical University, 2003), which consists in the treatment and prevention of the development of hypertrophic and keloid scars by transdermal administration of collagenase against the background of conventional therapy and additional intradermal administration of lidase in therapeutic doses.

The disadvantage of this method is the narrow clinical application that is not related to nerve injury, the need for additional administration of another substance and its course application.

Object of the invention: the creation of a method for the prevention of cicatricial compression of a nerve with its trauma and trauma to surrounding tissues, the subsequent development of peripheral paralysis and paresis.

The task is achieved by intraoperatively administering to the experimental animal a sterile aqueous solution of a resorbable biologically inert hydrogel of a polymer of sodium salt of carboxymethyl cellulose in an amount of two milliliters to the area of traumatic nerve damage in such a way as to create a “barrier” between the nerve and the injured tissues.

The invention is illustrated by drawings:

1. in figure 1 - nerve tissue on the 14th day after its mechanical injury and the introduction of the gel (series 1 - "experience"). Okr. picrosirius red. SW 8 × 20 × 6;

2. in figure 2 - nerve tissue on the 14th day after its mechanical injury without gel administration (series 2 - "model"). Okr. picrosirius red. SW 8 × 20 × 6;

3. in figure 3 - tissue of the intact nerve (series 3 - "control"). Okr. picrosirius red. SW 8 × 8 × 6;

4. in figure 4 - the nerve and surrounding tissue on the 14th day after its mechanical injury and the introduction of the gel (series 1 - "experience"). Okr. picrosirius red. SW 8 × 8 × 6;

5. in figure 5 - the nerve and surrounding tissue on the 14th day after its mechanical injury without the introduction of the gel (series 2 - "model"). Okr. picrosirius red. SW 8 × 20 × 6;

6. in figure 6 - the nerve and surrounding tissue in an intact animal (series 3 - "control"). Okr. G-e. SW 8x8x6;

7. in figure 7 - tissue peripheral with respect to nerve muscle injury on day 14 after modeling the injury and use of the gel (series 1 - "experience"). Okr. G-e. SW 8 × 20 × 6;

8. in figure 8 - tissue peripheral with respect to nerve muscle injury on the 14th day after modeling the injury without the use of gel (series 2 - "model"). Okr. G-e. At century 8 × 20 × 6;

9. figure 9 - tissue of the intact muscle (series 3 - "control"). Okr. G-e. SW 8 × 20 × 6.

The method is as follows. During the surgical intervention, two milliliters of a sterile absorbable biologically inert polymer hydrogel, necessary to create a “barrier” (hydroflotation effect), are introduced into the area of traumatic nerve damage (rupture of the nerve fiber with its subsequent stitching or traumatic compression) with a sterile syringe. It forms a “barrier” (the space between the nerve and the surrounding tissues) between the surface of the nerve and the surrounding tissues, which prevents the growth of connective tissue and cicatricial compression of the nerve fiber. The presence of a hydrogel in the area of injury improves the regeneration of nerve tissue, which helps to restore nerve conduction.

An example of a specific implementation. To simulate a nerve injury, Wistar rats were used without signs of quarantined diseases and contained in a rational food and drink diet under vivarium conditions.

All animals were divided into three series. The animals of the first two series with a Mosquito-type clamp applied an injury to the sciatic nerve by squeezing it until the first click of the cremallera within 1 second; further, the lateral and medial muscle groups were identically injured 5 mm higher, 5 mm below the site of the nerve injury and at its level. In the first series, after modeling a standard injury, a resorbable biologically inert hydrogel was introduced, the polymer of the sodium salt of carboxymethyl cellulose, which was not produced in the second series. The third series was composed of intact animals.

In all animals, after 14 days under general anesthesia, the morphological and functional state of the nerve structures under cicatricial compression and their changes depending on the use of a prophylactic barrier agent were studied. Then the animals were withdrawn from the experiment by an overdose of anesthesia. To diagnose sciatic nerve damage, we used the method of stimulation electromyography: under general ether anesthesia, we determined the parameters of the motor response (M-response) of the gastrocnemius muscle of animals. To amplify and record the M-response, a MG-42 four-channel myograph ("Medicor") was used. Electrodes were introduced into the projection area of the sciatic nerve. The studied nerve was stimulated with rectangular pulses of 0.2 ms duration and intensity from 0.1 to 50 V. The M-response was carried out by needle electrodes, which were inserted at right angles into the abdomen of the calf muscle. Electromyographic (EMG) diagnostics examined muscles innervated by the affected nerve, as well as symmetrical muscles on the unaffected side for control. The amplitude, duration, and latent period of the M-response of the calf muscles were compared. The degree of denervation processes in the muscles was judged on the degree of nerve damage.

The results of electrophysiological studies are presented in the table.

Conductivity of the nerve fiber according to the results of electrophysiological studies Experimental series results R Intact limb (control) one hundred% - Injury (model) 51.6% ± 3.4% - Injury + Na-CMC gel 75% ± 4.1% <0.001 * * - reliability in relation to the model

The table shows that the use of polymer hydrogels as a barrier means can improve the restoration of nerve fibers, and therefore its conductivity. The hydrogel polymer of the sodium salt of carboxymethyl cellulose significantly exceeds 25.4% nerve recovery after injury without the use of barrier agents.

To assess morphological changes, the biopsy specimen of the nerve trunk with surrounding tissues was subjected to histological examination with staining of the preparations with hematoxylin-eosin, picrosirius-red and according to Mallory.

In the experimental series, where a nerve was injured without the use of barrier agents (model), during a histological study on day 14 it was found that there is a change in the chic properties of the myelin sheath of the nerve, which acquires red-orange and purple hues. The diameter of the myelin fiber and axial cylinder is expanded. The combination of basophilic and acetophilic coloration with a predominance of basophilic elements. Nerve bundles lag behind epineuria, in their thickness there are voids and fibers with the formation of collagen, an abundance of capillaries and vascular sprouting. In the connective tissue surrounding the nerve, there is extensive inflammation, infiltration with an abundance of densely spaced fibers. In injured muscles, the spread of ischemic and dystrophic changes, basophilia.

In experimental series where barrier agents were used for nerve injury (hydrogel polymer of sodium carboxymethyl cellulose) and where there were intact animals (control), no such changes were detected.

Thus, the method for the prevention of cicatricial compression of the nerve and the development of peripheral paralysis and paresis using the carboxymethyl cellulose sodium salt polymer as a hydrogel barrier can be the basis for the treatment of traumatic nerve damage and significantly improve the results of neurosurgical operations due to the high efficiency of the gel in the restoration of damaged nerve fiber (restoration of conductivity nerve by 75%).

Claims (1)

A method for the prevention of cicatricial compression of a nerve, traumatic peripheral paralysis and paresis, including intraoperative administration of a sterile hydrogel to an experimental animal, characterized in that the hydrogel polymer of sodium salt of carboxymethyl cellulose is administered to the experimental animal in an amount of two milliliters in the area of traumatic nerve damage so as to create a "barrier" between nerve and injured tissues.

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