What imaging modalities are recommended for the diagnosis of pneumothorax in primary care?

In primary care, the recommended imaging modality for diagnosing pneumothorax is a chest X-ray, typically an upright posteroanterior or anteroposterior radiograph. This is the standard initial investigation to confirm the presence of air in the pleural space and assess its size and clinical significance ¹.

Point-of-care ultrasound (POCUS) is increasingly recognized as a valuable adjunctive tool for pneumothorax diagnosis, especially in settings where immediate radiography is not available or in unstable patients. Ultrasound can detect the absence of lung sliding and the presence of a lung point, which are indicative of pneumothorax, and has shown higher sensitivity than supine chest X-rays in emergency settings (Chan et al., 2020).

However, in primary care, ultrasound use depends on practitioner training and equipment availability, and chest X-ray remains the first-line imaging modality recommended by UK guidelines ¹.

Therefore, the integrated approach is to use chest radiography as the primary diagnostic imaging in primary care, with point-of-care ultrasound as a useful supplementary tool when accessible and when clinical suspicion remains high despite a negative or inconclusive X-ray.