Final answer:
Horner's syndrome affects the sympathetic nervous system and is clinically significant as it can indicate an underlying pathology.
Step-by-step explanation:
Horner's syndrome is a condition that affects the sympathetic nervous system. In this syndrome, the sympathetic pathway from the hypothalamus to the eye is disrupted. This results in several characteristic symptoms, such as pupillary constriction, drooping of the eyelids, and decreased sweating in the face.
The clinical significance of Horner's syndrome lies in its diagnostic value. It can indicate the presence of an underlying pathology, such as a tumor or injury, affecting the sympathetic pathway. By identifying and investigating the underlying cause, appropriate treatment can be initiated.