22 meniscus (air crescent) sign

CLINICAL IMAGAGING�AN ATLAS OF DIFFERENTIAL DAIGNOSIS�EISENBERG

1. 22 Meniscus (Air-Crescent) Sign *

2. CLINICAL IMAGAGING AN ATLAS OF DIFFERENTIAL DAIGNOSIS EISENBERG DR. Muhammad Bin Zulfiqar PGR-FCPS III SIMS/SHL

3. Fig C 22-1 Aspergillosis. A mycetoma (solid arrow) appears as a homogeneous rounded mass that is separated from the thick wall of the cavity by a crescent-shaped air space (open arrows).

4. Fig C 22-2 Aspergillosis. Multiple cavities of various sizes are superimposed on a diffuse pulmonary infiltrate. A fungus ball almost fills the large cavity in the right upper lobe (arrows). A right pleural effusion is also seen in this patient with chronic lymphocytic leukemia.

5. Fig C 22-3 Aspergillosis. Bilateral aspergillomas in an elderly man with residual tuberculosis. CT scan shows large cavities in the upper lobes containing fungus balls of different sizes. 41

6. Fig C 22-4 Hydatid cyst. A crescent of air (arrows) is seen about the periphery of the echinococcal cyst.