What are the symptoms of Horner's syndrome?

Horner's syndrome is characterized by a specific triad of symptoms resulting from disruption of sympathetic nerve pathways to the eye. The correct answer highlights two prominent features: pupillary miosis (constriction of the pupil) and facial anhidrosis (lack of sweating on the affected side of the face).

Pupillary miosis occurs due to the unopposed action of the parasympathetic nervous system when the sympathetic nerve supply is compromised, leading to constriction of the pupil. Facial anhidrosis arises because the sympathetic nerves that normally stimulate sweat production are affected, resulting in decreased sweating on the ipsilateral side of the face.

The other options do not align with the clinical presentation of Horner's syndrome. Severe headaches and light sensitivity relate more to conditions affecting the cranial nerves or migraines rather than the sympathetic nervous system. Seizures and loss of consciousness are indicative of neurological dysfunctions, potentially involving electrical activity in the brain, which is unrelated to Horner's syndrome. Similarly, respiratory difficulties and epilepsy refer to entirely different pathophysiological processes and symptoms not associated with the features of Horner's syndrome. Therefore, pupillary miosis and facial anhidrosis stand out as the defining symptoms of this condition.