Lung inhomogeneities, inflation and [18F]FDG uptake rate in ards

Results 5 patients presented mild, 12 moderate and 3 severe ARDS. In mild and moderate ARDS a consistent lung fraction is homogeneous with a high [F]FDG metabolic activity (53 ± 14% and 53 ± 20%). Inhomogeneous lung fraction with a higher [F]FDG uptake increases from mild to severe (12 ± 3%, 16 ± 9% and 27 ± 11%). On the other hand, the homogeneous parenchyma with normal [F]FDG uptake decreases in worse ARDS (33 ± 14%, 26 ± 20% and 5 ± 9%). Conclusions Our findings indicate that the actual classification of ARDS from mild to severe reflects the underlying pathophysiology. In fact, while a similar sized homogeneous and inflamed/metabolically more active compartment is present in all the ARDS patients, in mild ARDS it is associated with a consistent fraction of normal lung while in severe ARDS is primarily associated with inhomogeneous, inflamed/metabolically more active lung tissue.