TABLE 3.
Criteria for CT-based pulmonary fibrosis staging and PF-based severity grading (patent no: ZL 2019 1 0514972.5).
| PF Scoring criteria | SpO2% | FVC%pred | DLco%pred | Age (year) | Gender | Total severity score | Criteria for severity grading | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ≥95% | 90–94% | ≤89% | >75% | 50–75% | <50% | >55% | 36–55% | <36% | Cannot complete | ≤60 | 61–65 | >65 | M | F | 10 | a (mild) | b (moderate) | c (severe) | |||
| 0 | 1 | 2 | 0 | 1 | 2 | 0 | 1 | 2 | 3 | 0 | 1 | 2 | 1 | 0 | 0–3 | 4–6 | 7–10 | ||||
| CT-based staging criteria | I | Honeycomb lesion area is <5% of the entire lung | |||||||||||||||||||
| II | Honeycomb lesion area is 5–25% of the entire lung | ||||||||||||||||||||
| III | Honeycomb lesion area is >25% of the entire lung | ||||||||||||||||||||
| CTPF stage presentation example | Fibrosis stage/severity | Definition | |||||||||||||||||||
| II a | Fibrosis stage II and IPF severity grade a (mild) | ||||||||||||||||||||
Notes: SpO2%: oxygen saturation of peripheral blood. SpO2% is the resting arterial oxygen saturation measured at fingertips. FVC: forced vital capacity. FVC%pred: the percentage of the actual FVC over the predicted FVC. DLco: diffusing capacity of the lung for carbon monoxide. DLco%pred: the percentage of the actual DLco over the predicted DLco.