Sympathetic Ganglion

The sympathetic trunk begins to develop between the 3rd and 4th weeks of intrauterine life and ends in the chest cavity at the Th2-Th3 level. The formation of sympathetic cells occurs earlier than the formation of pathways for the stem vagal reflex arc; It develops more heterochronically in the embryo. The cells of the sympathetic system begin to differentiate from the cellular material of the subepidermal neural crest and the invagination of the trigeminal nerve ending (in the region of the rudimentum ciliare), which gives rise to the neurons of the medulla of the eyeball and the olfactory nerve. Further differentiation cells