LAUSR

A 9-y-old girl presented with lethargy, fatigue, and progressive exertional dyspnea for the last two–three years, and rapid breathing for the past six months. Chest radiograph showed confluent air-space opacities in both lungs. Chest computed tomography (CT) scan done outside 3 mo earlier showed diffuse ground-glass opacities with interstitial thickening suggestive of crazy paving in bilateral lungs (Fig. 1a). To evaluate the disease progression without the radiation exposure associated with another CT scan, magnetic resonance imaging (MRI) was performed. It showed diffuse hyperintense areas bilaterally on T2 turbo spin echo and MultiVane XD sequences, indicative of ground-glass changes (Fig. 1b and c). Radiologically, a possibility of pulmonary alveolar proteinosis (PAP) was given. Subsequently, bronchoalveolar lavage and lung biopsy confirmed PAP. In PAP, the phospholipidoproteinaceous material which deposits within the alveoli presents with longer T2 relaxation time, and longer or equal T1 relaxation time, which results in hyperintense signal, as seen in the index case. With the recent advances in lung MRI, short-duration protocols are able to give diagnostic information similar to CT in children [1, 2], thereby emerging as an attractive radiation-free modality. MRI can demonstrate the findings of PAP similar to CT, and may be relatively better than CT in picking up the parenchymal changes associated with PAP [3]. To conclude, MRI may serve as an attractive radiationfree modality in diagnosing PAP in children and evaluating the lung changes over time.