Fig. 6From: Clinical and radiological features of lung disorders related to connective-tissue diseases: a pictorial essayCoronal multiplanar reformatted images. A, B demonstrate the presence of straight-edge sign in female RA patients showing interstitial lung fibrosis. This sign consists of a more pronounced fibrosis in the lung bases—with sharp demarcation in the cranio-caudal plane (white arrows in A, B)Back to article page