Ultrastructural Study On Demyelination Of Peripheral Nerve Branches Of Trigeminal Neuralgia

The etiology and pathogenesis of primary trigeminal neuralgia is still unclear. Whether medications or surgical managements can not achieve satisfactory curative effect. Hence, making the etiology and pathogenesis more clear is the most important basic for improving the managements of the disease. In the present reports, we haven't found the quantitative analysis reports about whether there are any qualitative and quantitative differences of the demyelination among the diseased and undiseased nerve fibres of the patients afflicted with the trigeminal neuralgia,and the normal nerve fibres of the counterparts. We recruited the nerves resected in the neurotomy surgeries and other relevant surgeries as the specimens to perform the following investigations.1, To investigate the structures, respectively under the light and electron microscope,of the diseased and undiseased branches of the trigeminal nerve of the patients afflicted with the disease, and the normal nerve branches of the counterparts without the disease. Our investigations demonstrated that the delmyelination can be both found in the diseased nerve branches and the two control groups, nevertheless, the degrees and magnitudes of the demyelination of the diseased nerve branches were significantly more serious than those of the two control groups. 2,To quantitatively analysis the degree of the demyelination of the four groups of specimens. We applied the image analysis system to measure the squares of the cross-section of the studied nerve fibres, the squares of the cross-section of their axons, and the relevant rations of them , moreover,recruited the three groups of values as three testing parameters to compare the differences among the four group specimens and to test them by statistical means。The result showed: (1) In the same patient alone, the demyelination in the diseased nerve branch was even more serious than that in the undiseased one. (2) In the patients of the trigeminal neuralgia, both the demyelination in the distal to cranial cavity segments and in the cranial cavity proximal segments were more serious than the normal nerve branches of the counterparts with the same range of age. (3) Of the demyelination,there was not significant difference between the undiseased nerve branches of the patients and the normal nerve branches of the counterparts with the same range of age.Based on the foregoing investigations, we may achieve the following conclusions: (1) Our investigations may provide a assured basis to the peripheral theory. Considering the axon of the diseased nerve branch degenerated much more serious than that of the undiseased one in the same individual, we may confirm that the demyelination in the peripheral nerve fibres forms a pathological base to the pathogenesis of trigeminal neuralgia , and respondingly we should , in the research of the management of it, put emphasis on how to relieve or eliminate the demyelination and the effect incurred.(2)Although the demyelination may be found in the nerve fibres of the aged men, but the demyelination in the diseased nerve branch was much more serious than that in the undiseased one or that of the man without the disease. In respect to these findings, we propose that how to prevent the demyelination to become more serious, is the critical problem to settle, for the men without the trigeminal neuralgia to prevent the disease to arise. (3) Concerning the demyelination in the distal to cranial cavity segments and in the cavity proximal segments in the diseased nerve branch were both serious, we suggest by all means to resect the diseased nerve branch at the level more proximal to the skull base in the neurotomy surgery , so as to remove the diseased nerve branch more clearly, to raise the curative efficiency.