n. (in anatomy) a process, outgrowth, or extension of an organ or other structure. It is often paired. In the spinal cord crescent-shaped areas of grey matter (seen in cross section) are known as the dorsal and ventral horns.
A group of physical signs (narrowing of the eye pupil, drooping of the eyelid, and absence of sweating) affecting 1 side of the face that indicates damage to part of the sympathetic nervous system (see autonomic nervous system).... horner’s syndrome
This is the description given to a combination of changes resulting from paralysis of the sympathetic nerve in the neck. They are: a small pupil; a drooping upper lid; and an apparently (though not actually) sunken eye.... horner’s syndrome
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