Nodular Opacities

The presence of micronodules or cysts excludes a confident diagnosis of UIP.45 On HRCT, micronodules are discrete, round, soft-tissue densities of <3 mm.7 Cysts are low attenuation areas that tend to be round and thin-walled (<2 mm). Cysts in the lung often contain air but may also contain fluid or solid material.7