[Deferred Horner syndrome following thoracoplasty]

Horner syndrome (HS) involves an injury affecting the ocular sympathetic nerve, which gives rise to myosis, palpebral ptosis and enophthalmos, and is accompanied by hemifacial anhidrosis in its complete forms. Its extension means that its involvement can occur in different structures and as a result of different medical and surgical processes.

We describe the case of two patients who developed a subacute form of HS without involvement of the sweating process and which was not accompanied by any other clinical features affecting the orbit, neck, brain, spinal cord or of a radicular nature. Both of them had been submitted to thoracoplasty as therapy for tuberculosis over 30 years earlier. The complementary studies that were conducted did not reveal involvement of the ocular sympathetic nerve anywhere other than in the pleura.

The lesion would have been produced in the endothoracic fascia, where the cervical sympathetic chain is closely related to the apical pleura, and the physiopathological mechanism would be fibrosis of the aforementioned structures. Many reports have been published that describe the onset of HS as an acute complication following thoracic surgery, but its late development is infrequent.