From: Quantitative lung SPECT applied on simulated early COPD and humans with advanced COPD

Distribution notation | Coronal slice | Number | Distribution description | Total reduction of ventilation (%) | |
---|---|---|---|---|---|

Simulated normal | Uniform | 1 | Homogeneous activity distribution | 0 | |

Simulated COPD |
1 cm^{50%} 10% evenly
| 2 | Lesions with a diameter of 1 cm with 50% activity concentration, evenly distributed over the lung volume, occupying 10% of the total lung volume. | 5 | |

1 cm^{50%} 12% centred
| 3 | Lesions with a diameter of 1 cm with 50% activity concentration, centred to the large bronchial tubes, occupying 12% of the total lung volume. | 6 | ||

1 cm^{0%} 10% evenly
| 4 | Lesions with a diameter of 1 cm with 0% activity concentration, evenly distributed over the lung volume, occupying 10% of the total lung volume. | 10 | ||

1 cm^{0%} 12% centred
| 5 | Lesions with a diameter of 1 cm with 0% activity concentration, centred to the large bronchial tubes, occupying 12% of the total lung volume. | 12 | ||

2 cm^{50%} 10% evenly
| 6 | Lesions with a diameter of 2 cm with 50% activity concentration, evenly distributed over the lung volume, occupying 10% of the total lung volume. | 5 | ||

2 cm^{0%} 10% evenly
| 7 | Lesions with a diameter of 2 cm with 0% activity concentration, evenly distributed over the lung volume, occupying 10% of the total lung volume. | 10 | ||

2 cm^{50%} 48% evenly
| 8 | Lesions with a diameter of 2 cm with 50% activity concentration, evenly distributed over the lung volume, occupying 48% of the total lung volume. | 24 | ||

2 cm^{25%} 48% evenly
| 9 | Lesions with a diameter of 2 cm with 25% activity concentration, evenly distributed over the lung volume, occupying 48% of the total lung volume. | 36 |