High-resolution computed tomography of interstitial pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF), also referred to as cryptogenic fibrosing alveolitis (CFA), is the clinical-radiological-pathological syndrome associated with the most common form of fibrosing interstitial pneumonia, usual interstitial pneumonia (UIP). Unfortunately, the diagnosis of IPF carries with it a relatively poor prognosis. The characteristic features on high-resolution computed tomography (HRCT), consisting of reticular abnormality and honeycombing with basal and peripheral predominance, are virtually diagnostic within the correct clinical context. The extent of fibrosis on HRCT is an important prognostic indicator. When ground-glass attenuation is seen in patients with IPF, it commonly progresses to fibrosis and honeycombing. Complications of IPF include accelerated progression and deterioration, lung cancer, spontaneous air leak, and secondary infection. This article discusses the key imaging features as correlated with histopathology, differential diagnosis, complications, and follow-up evaluation of idiopathic pulmonary fibrosis.