Deep sulcus sign

In radiology, the deep sulcus sign on a supine chest radiograph is an indirect indicator of a pneumothorax. In a supine film, it appears as a deep, lucent, ipsilateral costophrenic angle within the nondependent portions of the pleural space as opposed to the apex when the patient is upright. The costophrenic angle is abnormally deepened when the pleural air collects laterally, producing the deep sulcus sign.


In radiology, the deep sulcus sign on a supine chest radiograph is an indirect indicator of a pneumothorax. In a supine film, it appears as a deep, lucent, ipsilateral costophrenic angle within the nondependent portions of the pleural space as opposed to the apex when the patient is upright. The costophrenic angle is abnormally deepened when the pleural air collects laterally, producing the deep sulcus sign.
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