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Figure 10. UIP Pattern Due to Connective Disease CTD-
UIP Pattern in a Patient With Dermatomyositis/
Scleroderma Overlap
Axial and coronal images show sharply demarcated fibrosis with exuberant honeycombing in the lower
lobes, and in the anterior upper lobes. CTD-UIP should be considered when honeycomb cysts are
extensive, occupying more than 70% of the fibrotic portions of the lung (exuberant honeycombing
sign), when fibrotic abnormality is sharply demarcated on coronal images from the relatively normal
upper lungs (straight-edge sign), and when there is relative increase in fibrosis in the anterior upper
lobes (anterior upper lobe sign).
