Deep sulcus sign is seen in
High-Yield Explanation
Deep Sulcus sign is seen On Supine chest x-ray in Expiration phase in a case of Pneumothorax where the lucency of air in the costophrenic angle gives the appearance of a deep sulcus. Other Findings of Pneumothorax on CXR: Absent Bronchoalveolar markings Visceral Pleural Reflection