The anatomic features and pathologic abnormalities of teased sural nerve fiber from normal adults / 中华神经科杂志

ABSTRACT

Objective To evaluate the teased fibers and the consecutive internodes or segments of the same myeliated nerve fiber. Methods Measurements were performed on 1100 fibers (5522 internodal segment) from 11 control nerves as to detecting the anatomic features and pathologic abnormalities. Results Morphometric study on normal teased fibers revealed three results: (1) There is a certain variation of diameters (Ds) and length (IL) of the internodal segments along a fiber (1.0—2.5 ?m), and as a rule, the longest segment is not the thickest one, and the shortest segment is not the thinnest. Or even, sometimes the thinnest segment is the longest one in all internodal segments. (2) The relationship between IL and Ds is not linear, but shows a parabolic curve; thick segments are relatively shorter than the thinner segment. (3) The IL of segment along 10—20 mm of a fiber may be varied by maximally 50%; on the different IL, there is no casual distribution of internodal segments, but 2—4 (or even 6) segments of about equal length are grouped in a row. Conclusions On the classification of normal teased fibers, myelin of the internode may be ragular, irregular and variable in thickness among internodes.