Table 2.

Advanced Analysis Tools

Advanced Analysis Tool	Use	Current Clinical Usefulness
CT scan imaging densitometry or QCT scan imaging	•Routinely used for BLVR •Recently suggested for patients being evaluated for LVRS •Provides information about distribution of disease (homogenous vs heterogenous), degree of emphysema per lobe, lobar volumes, and fissure integrity •Routinely used to calculate LAAs, which correlates with degree of clinical impairment, and PD15, which provides sensitive metric of disease progression in early lung disease •Ongoing efforts to have QCT imaging qualified as biomarker with FDA as an acceptable outcome measure for therapeutic interventions •Cornerstone of central airway morphologic assessment	•Widely used and well accepted in academic centers •Expanding availability to the community
Parametric response mapping	•Can distinguish functional small airways disease from emphysema •Has identified less functional areas of the lung that potentially may be targeted for bullectomy or BLVR	•Widely used and well accepted in academic centers •Expanding availability to the community
Machine learning or deep learning	•Has ability to classify phenotypes and stratify disease severity from CT scan imaging	•Research setting

BLVR = bronchoscopic lung volume reduction; FDA = US Food and Drug Administration; LAA = low attenuating area; LVRS = lung volume reduction surgery; PD15 = lowest 15th percentile of lung histogram; QCT = quantitative analysis CT.