[Morphometric analysis of diameter and density of myelinated and unmyelinated fibers of normal human sural nerves].

Diameter and density of both myelinated and unmyelinated fibers were morphometrically analyzed in 8 sural nerves obtained from 8 normal volunteers by utilizing a TGA-10 particle analyzer (Carl Zeiss Co., West Germany). The density of total myelinated fibers was (7.4 +/- 1.3) X 10(3) (mean +/- standard deviation) per square millimeter. The border diameter between small and large myelinated fibers was 5.4 +/- 0.5 micron. The densities of small and large myelinated fibers in cross sectional areas were (4.5 +/- 0.9) X 10(3) and (2.9 +/- 0.7) X 10(3) per square millimeter, respectively. The density of unmyelinated fibers was (27.9 +/- 5.8) X 10(3) per square millimeter. The peak and the median diameters in the size distribution of unmyelinated fiber diameters were 0.88 +/- 0.15 and 0.86 +/- 0.12 micron, respectively. The mean distribution histograms of the sizes of both myelinated and unmyelinated fibers of 8 sural nerves were also established. The morphometric findings obtained in this study serve as control in histopathologic analysis of the sural nerves from the patients with various peripheral neuropathies.

[Reliability of the evaluation of the active sweat gland density on the dorsum of the foot using the silastic impression mold technique].

The evaluation of the density of the active sweat gland on the dorsum of the foot induced by iontophoresis of 1% pilocarpine was made repeatedly using the silastic impression mold technique in 83 subjects (52 normal volunteers: 24 subjects younger than 50 years of age and 28 subjects 50 years of age or older, 20 men and 32 women: 20 diabetic patients and 11 patients with other neurological disorders), from 12 to 82 years of age, and the reliability of such evaluation was assessed. After 8 to 14 days following the first evaluation, the second one was performed. The reliability was expressed as an intra-class correlation. The intra-class correlation was greater in the subjects 50 years of age or older (0.909) than in the subjects younger than 50 years of age (0.653). It was similar between males (0.921) and females (0.803). On the other hand, it was less in diabetic patients (0.543) than in the normal volunteers (0.857) and patients with other neurological disorders (0.809). The silastic impression mold technique is widely applicable in evaluating the sweat gland function. However, it should be kept in mind that the reliability is variable among the groups defined clinically and that it is low in the diabetic patients.