A pseudocavity appears as an oval or round area of low attenuation in lung nodules, masses, or areas of consolidation that represent spared parenchyma, normal or ectatic bronchi, or focal emphysema rather than cavitation. These pseudocavities usually measure less than 1 cm in diameter. They have been described in patients with adenocarcinoma, bronchioloalveolar carcinoma, and benign conditions such as infectious pneumonia. [from
HPO]