| FEV | familial exudative vitreoretinopathy; forced expiratory volume |
|---|---|
| FEV1, | FEV1 forced expiratory volume in one second |
| I/E | inspiratory/expiratory [ratio]; internal/external |
| I:E | inspiratory/expiratory [ratio] |
| LEEP | left end-expiratory pressure; loop electrosurgical excision procedure |