Visualization of the Paranasal Sinuses*
| Maxillary | 2 - 3 mo |
| Ethmoidal | 3 - 6 mo |
| Sphenoidal | 1 - 2 y |
| Frontal | 8 -10 y |
* The radiographic visualization of the sinuses lags the actual gross appearance based on autopsy.Kirks DR. Griscom NT. Practical Pediatric Imaging. Lippincott - Raven: Philadelphia. 1998.