When this nerve is injured, it causes Horner's syndrome, which is a triad of three symptoms: meiosis or constricted pupil, ptosis (a droopy eyelid), and anhidrosis (the inability to sweat).

T1受损会引起Horner综合征，由一组三联征构成——瞳孔缩小、上睑下垂、无汗。

This leads to Horner's syndrome on the same side of the face as the lesion, which include symptoms of miosis or constricted pupil, ptosis or droopy eyelid, and anhidrosis or failure to sweat.

这会导致在病损同侧脸部出现霍纳综合征，症状包括瞳孔缩小、眼睑下垂与脸部无汗。

Cluster headaches, another primary headache type, cause burning, stabbing bursts of pain behind one eye, leading to a red eye, constricted pupil, and drooping eyelid.

丛集性头痛是另一种原发性头痛类型，会导致一只眼睛后方出现灼痛、刺痛，导致眼睛发红、瞳孔收缩和眼睑下垂。

If a pancoast tumor pushes on or invades these sympathetic nerves, it can cause miosis - a small or constricted pupil, ptosis - a droopy eyelid, and anhydrosis - a failure to sweat, all on the ipsilateral, or same side, of the face as the nerve.

如果肺上沟瘤向上挤压或侵袭交感神经，则会出现瞳孔缩小、上睑下垂、无汗等症状，这些都发生于神经支配的同侧面部。