• Functional physiology and measurement: a dominant paradigm that ties disease to quantifiable lung function—ventilation distribution, total lung capacity, and diffusing capacity—anchoring pathology to measurable impairment across diseases [10], [11], [8], [15], [2], [13].

• Emphysema and COPD pathology emphasize subtypes (centrilobular, generalized), chronic bronchitis, smoking associations, and airway remodeling; including hypertrophic emphysema and disease progression [14], [7], [9], [17], [19], [12].

• Interstitial fibrosis and fibrotic lung disease cluster links acute and chronic fibrotic processes to function, advancing classification through patterns of fibrosis, diffusion impairment, and sarcoidosis context [5], [2], [13], [4], [16].

• Cardio-pulmonary interactions show how chronic lung disease reshapes cardiac function and systemic circulation, highlighting hemodynamic consequences of respiratory impairment [18], [20].

• Morphology and evolution of disease: pathology-driven classification traces how acute bronchiolitis, emphysema variants, chronic bronchitis, and fibrotic changes develop, shaping diagnostic taxonomy [6], [7], [9], [17], [16].