Aging process of the human lumbar spinal cord: A morphometric analysis

Abstract

A morphometric evaluation according to the aging process was made on the human spinal cord. The staining characteristics disclosed that the posterior funiculus became paler with age, the motor neurons were partially lost in the anterior horn, and the amyloid bodies accumulated in quantity in the posterior funiculus. We made a further morphometric analysis for precise evaluation. Diameters and areas of transverse sections of the cord (Tr), white matter (W), gray matter (G) and posterior funiculus (Pf), areal ratios of posterior funiculus over transverse section (Pf/Tr), posterior funiculus over white matter (Pf/W), gray matter over white matter (G/W) and gray matter over transverse section (G/Tr), were measured and calculated on the transverse sections of the first lumbar segment, using an image analyzer and a computer. Results indicated that the area of posterior funiculus became reduced with age, but the size of transverse sectional areas had no correlation with the aging process. A significant correlation could be seen between the ratios of Pf/Tr and age on one hand, and Pf/W and age on the other. The ratios of G/W and G/Tr showed a tendency to decrease according to the aging process, although correlation analysis showed this to be of low statistical significance. In human material, the morphometric evaluations are considered to be useful in explaining several clinical phenomena in relation to geriatric neurology and in comparing various pathologic conditions with the normal aging data.