Computed tomography of combined right upper and middle lobe collapse.

We report two patients with combined right upper and middle lobe collapse and present the CT findings. The CT appearance is different from isolated right upper or middle lobe collapse, but similar to left upper lobe collapse. As with other types of lobar collapse, the diagnosis can usually be made from frontal and lateral chest radiography. However, occasionally the exact type of lung collapse may be unclear prior to CT, and thus CT may be useful in making the correct diagnosis.