Thorax HRTC Scan of the two brothers with the homozygous ABCA3 mutation. a, b) Patient B. Diffuse areas of reticular ground glass opacities, prevalent in the upper right lobe. Initial honeycombing in the dorsal segment. Diffuse pleural thickening. c and d) Patient C. The involvement of the upper lobes is very similar to that of the brother, patient B.