Table 1 Predefined findings of the maxillary sinus

1.  Complete opacity

2.  Basal opacity

3.  Foreign body

4.  Oro-antral communication

5.  Basal septum

6.  Polypoid mucosal thickening

7.  Maxillary bone cyst penetrating into the sinus

8.  Fluid level

9.  Status post sinus lift

10.   No finding