Spontaneous pneumomediastinum in 33 patients: Yield of chest computed tomography for the diagnosis of the mild type

Background: Spontaneous pneumomediastinum (SPM) usually occurs in young peo ple without an apparent precipitating factor or disease. Although there hav e been many studies focused on the clinical features and standard chest X-r ay (CXR) findings of SPM, few have reviewed the chest computed-tomographic (CT) findings. Objectives: We assessed SPM using CXR and CT, and the relati on between them. Methods: We evaluated 33 patients (26 males) diagnosed wit h SPM on the basis of symptoms and chest radiological findings. Results: Th ree patients showed normal CXR but a diagnostic CT scan. Seven showed mild pneumomediastinum on CXR, In these 10 patients, pneumomediastinum was easil y detected by chest CT, Moderate and severe SPM were easily detected by bot h CXR and CT. Conclusions: These findings suggested that CXR alone poorly d etected approximately 30% of SPM and that chest CT scan was needed to make the diagnosis in these cases. It seems likely that SPM is underdiagnosed by 30% or more in clinical practice. Copyright (C) 2000 S. Karger AG. Basel.