Abstract
A premature infant who developed respiratory distress syndrome required artifical ventilation. A right-sided tension pneumothorax at the age of 78 h was treated by insertion of a P.V.C. chest tube reaching deep into the right upper chest. At discharge on day 51 a Horner's syndrome of the right eye was noticed. Detailed examination at the age of one year revealed a typical peripheral preganglionar Horner's syndrome. Because other causes could be ruled out we assume that the lesion of the sympathetic nerve fibers was caused by the tip of the chest tube near the first thoracic intervertebral space.