| Feature | DPO | NPO |
| Radiographic | Branching, dendritic; coral-like | Round with smooth contours, lobulated |
| Histological | In alveolar septa, tubular shape of bone | Within alveolar spaces, lobulated bone |
| Marrow | Present | Absent |
| Clinic | Associated with chronic obstructive lung disease and interstitial fibrosis | History of passive congestion & cardiac problems |