Figure 12c. Talc embolism in a 26-year-old woman. The patient had a 4-year history of heroin and methadone abuse. (a) Targeted view of the left lung from a chest radiograph shows widespread involvement of the lung by pinpoint micronodules. (b) CT scan (5-mm collimation, lung window) obtained at the level of the basal trunk shows extensive patchy areas of increased attenuation in both lungs. (c) Follow-up radiograph obtained 6 years later shows coalescent areas of increased opacity (progressive massive fibrosis) in the bilateral middle lung zones (arrows). Note also the emphysematous right upper lung zone. (d) Thin-section (1.5-mm collimation) CT scan (mediastinal window) obtained at the subcarinal level shows coalescent areas of increased attenuation (progressive massive fibrosis) posteriorly in both lungs. Note also the areas of high attenuation within the masses (arrow), a finding that suggests talc deposition.