Radiographic findings are highly diagnostic and include a rounded, tubular, or branching opacity pointing toward the ipsilateral hilum with surrounding pulmonary hyperlucency. These opacities may contain air-fluid levels when complicated by superimposed infection and can be seen with simultaneous hyperinflation in 57% to 83% of cases., Nonenhanced CT scans usually demonstrate low attenuation of impacted secretions (–5 to 25 HU). Regional oligemia in hyperlucent areas is suggested by reduced vessel diameters due to intrapulmonary vascular compression and hypoxic vasoconstriction. With contrast-enhanced CT scanning, the impacted mucocele should remain of low attenuation and without enhancement, distinguishing it from vascular lesions such as arteriovenous malformation or centrally obstructing neoplasm. The lack of a prominent feeding vessel further excludes the diagnosis of interlobar sequestration. Allergic bronchopulmonary aspergillosis may have a similar “finger in glove” appearance; however, it lacks adjacent hyperlucency, is frequently hyperattenuating on non-enhanced CT scans, and is typically seen in patients with allergies, asthma, or cystic fibrosis.