Ganglion

Mass of nerve-like cell bodies lying outside the brain and spinal cord.

A mass of nerve cells that serves as a center of nervous influence.

A mass of nerve cell bodies and synapses usually covered in connective tissue, found along the peripheral nerves with the exception of the basal ganglia.

A cyst of a tendon sheath or joint capsule, usually at the wrist, which results in a painless swelling containing fluid.

Collection of nerve cells forming a knotlike shape and usually lying outside the brain and spinal cord; in the autonomic nervous system, chains of ganglia lie on either side of the spinal cord.

A cyst that most commonly appears under the skin on the side of the wrist, hand, or the top part of the foot. They occur when a gel-like substance that leaks from a joint capsule accumulates and balloons out to form an external swelling or cyst. Ganglia are generally harmless and painless or only mildly painful, and they rarely impede movement of the wrist or foot. A doctor may determine that no treatment is necessary, or the decision may be made to aspirate or draw fluid from the cyst and sometimes to inject a corticosteroid drug. If these treatments are not successful, surgery may be considered.

Any structure containing a collection of nerve cell bodies and often also numbers of synapses. In the sympathetic nervous system chains of ganglia are found on each side of the spinal cord, while in the parasympathetic nervous system ganglia are situated in or nearer to the organs innervated. Swellings in the posterior sensory roots of the spinal nerves are termed ganglia; these contain cell bodies but no synapses. Within the central nervous system certain well-defined masses of nerve cells are called ganglia (or nuclei); for example, the basal ganglia.

This term is used in two senses. In anatomy, it means an aggregation of nerve cells found in the course of certain nerves. In surgery, it means an enlargement of the sheath of a tendon, containing fluid. The latter occurs particularly in connection with the tendons in front of, and behind, the wrist.

A mass of nervous tissue composed principally of neuron cell bodies and lying outside the brain or spinal cord (e.g., the chains of ganglia that form the main sympathetic trunks; the dorsal root ganglion of a spinal nerve).

Situated beyond the central nervous system, there exists a cluster of nerve tissue referred to as a mass.

A cluster of nerve cells, sharing a specific function, is one way to define such a group. For instance, the basal ganglia in the brain, which are tasked with managing muscle movements, serve as a perfect example of this.

The term is also employed to denote a fluid-filled lump linked with the cover of a tendon, known as a ganglion. Such a ganglion may naturally vanish over time, but if required, it can be drained or surgically excised.