Magnetic Resonance Lung Function Imaging Study of Pulmonary Fibrosis Combined With Emphysema Syndrome

Inclusion Criteria: * (1) Chest HRCT shows emphysema mainly distributed in the upper lung field, manifesting as wallless or thin-walled (wall thickness \<1 mm) low-transmittance areas with clear boundaries with normal tissue, or multiple bullae (diameter \> 1 cm), and the emphysema area/total lung volume is ≥10%; (2) interstitial pulmonary fibrosis mainly distributed in the lower lung field and subpleura, manifesting as honeycomb shadow or grid shadow, and the lung structure is destroyed , may be accompanied by traction bronchiectasis, ground glass opacities and consolidation opacities. Exclusion Criteria: * (1) Refusal to sign the informed consent form; (2) MRI contraindications (implanted pacemaker/defibrillator, claustrophobia, or any clinical condition that prohibits longer MRI examinations).