fig2

Figure 2. Thoracoscopic view of the left dorsal thoracic sympathetic chain. Axons from the first neuron (preganglionic) travel within the dorsal and ventral roots and form the preganglionic sympathetic fibers or rami communicantes albi (purple). Rami communicantes albi synapse with the second neuron within the sympathetic chain (blue), and postganglionic fibers or ramus communicantes grisei (green) travel with the intercostal nerves (red). The enlarged areas (ganglia) contain both nerve bodies of the second neuron and axons from neurons at other levels