Spinal Ganglion

Spinal ganglia are spindle-shaped nodes with a diameter of 5–8 mm. They are locate d in the posterior roots of the spinal nerves immediately before posterior and anterior roots merge. Each spinal ganglion is enveloped by a strong collagen fiber capsule 1 (= constituent of the spinal dura mater). Distally, it continues in the perineurium of the spinal nerve. Each ganglion is traversed by a delicate vascularize d connective tissue ( endoneurium of the spinal nerve ), which is continuous with the connective tissue of the capsule.  Embedded in this loose connective tissue are pseudounipolar nerve cell bodies and their satellite cells (= peripheral glial cells) as well as the axons of these primary sensory neurons of the spinal nerves.

1 Connective tissue capsule

2 Posterior root of the spinal nerve

Stain: azan; magnification: × 12

Spinal Ganglion

Vertical section of a spinal ganglion which is part of the posterior root of the spinal nerve ( radix posterior ) immediately before it merges with the anterior root and forms the spinal nerve. The anterior root of the spinal nerve is not shown. The figure shows fiber tracts, i.e., axon bundles of different sizes, which build the posterior root 1 or the posterior branch of the spinal nerve 2 , respectively. The black spots with different diameters represent pseudounipolar ganglia cells 3 . The spinal ganglion is encase d by a vascularized connective tissue capsule 4 , which is continues with the spinal dura mater .

1 Posterior root of the spinal nerve

2 Posterior branch of the spinal nerve

3 Group of ganglia cells

4 Connective tissue capsule

Stain: Bielschowsky -Gros silver impregnation; magnification: × 7

References

Kuehnel, W.(2003). Color Atlas of Cytology, Histology, and Microscopic Anatomy. 4^th edition . Institute of Anatomy Universitätzu Luebeck Luebeck, Germany . Thieme Stuttgart · New York .