Fig. 2— A 57-yr-old female with idiopathic pulmonary fibrosis and acute exacerbation showing multifocal patchy type. a) An initial high-resolution computed tomography scan shows the reticular opacity and honeycombing in the subpleural area of the lung. b) In follow-up computed tomography after 1 month, the ground-glass opacities of multifocal patchy distribution have developed in both lungs. The patchy ground-glass opacities are distributed randomly and the fine reticular opacities can also be seen within the ground-glass opacity.