On the Assessment of Preserved Ratio Impaired Spirometry

revealing the underlying biological mechanisms of ILA.Yet ILA has a relatively high prevalence of 3-17% among individuals undergoing chest computed tomography compared with ILD (2-5); as such, it may not be feasible or adequate to perform invasive diagnostic and therapeutic interventions immediately and routinely in those with newly detected ILA.This prompted us to stratify subjects with ILA on the basis of their risk of progression and establish appropriate imaging follow-up strategies.We hypothesized that computed tomography quantification parameters for fibrosis could be used as a biomarker, providing a more objective metric for risk assessment.On the basis of the results of our analysis, we have identified the quantified extent of fibrotic ILA percentage in the whole lung as an independent risk factor for radiologic progression.Furthermore, subjects with ILA can be stratified for radiologic progression and overall survival on the basis of the presence of honeycombing and the quantified extent of fibrosis (.5% fibrotic ILA in any lung zone or fibrotic ILA .1% in the whole lung).We expect that our results might help in identifying Pinocchios who are at high risk of developing into real boys and providing a personalized follow-up strategy for optimal observation and treatment.Last, as Putman and Hunninghake pointed out (6), the integration of physiological and clinical data with imaging would be important, and it would also be necessary to verify how our results can be replicated using other quantitative analysis programs or metrics in the future studies.