Swyer-James Syndrome

Swyer-James syndrome (SJS), also known as Macleod syndrome, refers to hypoplasia of a portion of or the whole lung caused by postinfectious obliterative bronchiolitis. It is thought to occur following acute bronchiolitis in infancy or early childhood. This early insult results in damage to the terminal and respiratory bronchioles, preventing normal development of alveolar buds.

Radiographic manifestations of SJS include pulmonary hyperlucency and pruning of vessels. On this radiograph, we can see that the left lung is smaller and more lucent compared to the right. In addition, the pulmonary vessels on the left are smaller and don't extend as far peripherally as those on the right.

CT demonstrates pruning of vessels and a mosaic attenuation pattern. Expiratory images show air trapping. On this coronal reformation, we can see decreased caliber of vessels on the left, with a relative hyperlucency.

References

• Ghossain MA, et al. Swyer-James syndrome documented by spiral CT angiography and high resolution inspiratory and expiratory CT: an accurate single modality exploration. J Comput Assist Tomogr. Jul-Aug 1997;21(4):616-8.
• Marti-Bonmati L, et al. CT findings in Swyer-James syndrome. Radiology. 1989 Aug;172(2):477-80.