{Reference Type}: Case Reports {Title}: Transient Horner's Syndrome: An Unusual Complication of Pneumothorax Treatment. {Author}: Fiallo P;Patel H;Devanathan NG;Yadav S;Biglione A; {Journal}: Cureus {Volume}: 16 {Issue}: 2 {Year}: 2024 Feb 暂无{DOI}: 10.7759/cureus.55033 {Abstract}: Horner's syndrome is a rare condition that results when there is an interruption of the sympathetic fibers that run from the stellate ganglion to the eye. The classic triad of Horner's syndrome includes unilateral ptosis, miosis, and anhidrosis. Spontaneous pneumothorax is a rare condition that occurs when there is a sudden collapsed lung without any direct cause. A few cases have been reported of spontaneous pneumothorax associated with iatrogenic Horner's syndrome. A chest thoracostomy is a procedure that can lead to iatrogenic Horner's syndrome. Here, we present the case of a 25-year-old male with a left-sided spontaneous pneumothorax complicated by iatrogenic Horner's syndrome secondary to chest thoracostomy.