How to identify pneumothorax on a chest x-ray

In this video, you'll learn to identify when radiological pleura is abnormal and the key signs to look out for when trying to diagnose a pneumothorax.

Want to master chest x-ray interpretation? Take our Chest X-ray Essentials course and learn how to interpret chest x-rays like a pro. Your instructor, Dr Julian Dobrowski–an award-winning author and Professor of diagnostic imaging at McMaster University in Ontario, Canada–will guide you through the essentials of chest X-rays.

[00:00:00] What will I gain from this video? After watching this video, you will know how to search for and identify a pneumothorax. The radiological pleura is abnormal if the pleural space becomes visible and the grayscale image is too black, too white, or too black and too white in combination. We have learned that the pleural spaces are potential space that can accumulate fluid and air. When air enters into the pleural

[00:00:30] space, it will rise to the most superior part of the thorax. If further air accumulates, then the air will accumulate lateral and even inferior to the lung. In order to identify pneumothorax, we need to identify the black air within the pleural space and to differentiate that from the air within the lungs. Here, we can see the pneumothorax within the right apex.

[00:01:00] There are no vascular markings identified whatsoever in this region, but we can also identify the clear margin of the lung because we can identify the visceral pleura, as this thin line outlining the lateral aspect of the lung, in this region. Can you identify the pneumothorax on this examination? Please pause the video and have a look.

[00:01:30] If we look at the apices of both lungs, we'll see that there is a slight asymmetry on the left as compared to the right, and that is because we have a pneumothorax on the left. This edge represents the edge of the lung. Knowing that it can be quite difficult to identify a pneumothorax on an inspiration film, if a pneumothorax is suspected, an expiration film should also be

[00:02:00] ordered. On an expiration film, the pneumothorax will be more evident because on expiration, there is less lung air, therefore, the lungs will look whiter, making the density difference between the pneumothorax and the lungs more evident, and the size of the pneumothorax will appear larger. In this case, an expiration film was obtained and the expiration film shows the large left pneumothorax as well

[00:02:30] as significant volume loss, within the left lung, on expiration. A tension pneumothorax is a pneumothorax that has increased in size significantly and is now causing displacement, of the mediastinal structures, to the contralateral side. When this happens, there can be cardiovascular compromise and this is a medical emergency. So, how do we identify a pneumothorax?

[00:03:00] The first step is to make sure that the patient is properly centered and is not rotated. Next, we need to understand what kind of examination was performed. In this case, we have markers telling us that this was an expiration film. Next, we look for asymmetry in the apical regions, knowing that the pneumothorax or the air within the pleural space will rise to the highest point. In this case, we can identify that the right apical region is blacker than on the

[00:03:30] left. The next step, is to look for the edge of the lung and here, we can clearly identify a thin line, which represents the visceral pleura. On this side of this line, there is increased blackness from the pneumothorax, confirming that this is a pneumothorax. If you're still having difficulties identifying the pneumothorax, then outline each of the ribs,

[00:04:00] on the suspected side. This is the first rib, the second rib, the third rib, superior cortical outline, inferior cortical outline, here's the superior cortical outline of the 4th rib, and inferior cortical outline of the 4th rib. Between the 3rd and 4th rib, there is an additional line and this is the edge of the pneumothorax. In this case, the patient will develop acute

[00:04:30] sharp chest pain. We see a large pneumothorax, which is causing collapse of the left lung and displacement of the mediastinal structures to the right. This is a large tension pneumothorax. This is another example of a tension pneumothorax, with significant collapse of the right lung and mediastinal shift to the left. Can you identify the pneumothorax on this case? Please

[00:05:00] pause the video and take a look. So, in this case, we can identify a linear density extending superiorly. This represents the edge of the lung and this is the pneumothorax. The expiration view exaggerates the appearance of the pneumothorax on the right. Can you identify the pneumothorax on this examination? Please

[00:05:30] pause the video and try. So, in this case, we can identify the clear line of the visceral pleura on the left apex and the paucity of markings and increased blackness within the left apex, consistent with a left apical pneumothorax. In this case, we have a large pneumothorax on the left, with areas of subsegmental atelectasis within the lung as well as

[00:06:00] overall volume loss within the lung and mild mediastinal shift to the right, consistent with early tension pneumothorax. In this case, the patient's had a previous pleural disease and has developed a pneumothorax. Because of the previous pleural disease, the air within the pleural space is unable to extend to the apices, giving this unusual loculated appearance to the pneumothorax.

[00:06:30] Can you identify the pneumothorax in this case? Please pause the video and take a look. So, in this case, again, we can identify a edge that should not be present, this is the edge of the lung and the visceral pleura, with a left-sided, small left-sided, apical pneumothorax. So, in summary, a small pneumothorax can be easily missed. A large pneumothorax can be life-threatening. Air in the pleural

[00:07:00] space will rise to the highest point. The thickness of the visceral pleura is similar to the thickness of the fissures.