Here are the main radiologic signs of collapse:
1. Loss of volume - The affected lobe or lung appears smaller in size compared to the contralateral side.
2. Increased radiolucency - The collapsed lobe appears whiter than normal lung tissue due to loss of aeration.
3. Loss of vascular markings - The normal bronchovascular markings are obscured in the collapsed area due to loss of lung expansion.
4. Mediastinal shift - The mediastinum shifts towards the side of collapse to occupy the space left by the collapsed lung.
5. Displacement of fissures - The fissures adjacent to the collapsed lobe are displaced or obliterated.
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