Background:
Ultrasound is the choice modality in the unstable patients and after performing certain procedures, such as a thoracentesis or the placement of a central venous line, which helps to rule out an iatrogenic pneumothorax. Upright AP radiograph has less sensitivity in diagnosing pneumothorax in comparison with ultrasound. Ct scan is more sensitive in diagnosis occult pneumothoraces but Bedside ultrasound is prefferedt in unstable situations without any radiation exposure.so we aimed to compare sensitivity of sonography with ct scan in patients who are suspicious to pneumothorax after thoracentesis or the placement of a central venous line or intubatin.