If the petrous ridge is projected over the floor of the maxillary sinuses in a Waters method projection, what adjustment should be made?

The Waters method, also known as occipitomental projection, is used to visualize the maxillary sinuses. In this method, the patient's orbitomeatal line (OML) should be perpendicular to the image receptor, and the x-ray beam is directed through the mentum. When the petrous ridges are projected over the floor of the maxillary sinuses, it indicates that the OML is not sufficiently perpendicular; consequently, the skull is not extended enough.

By extending the neck further, you adjust the angle of the OML to achieve the proper alignment, allowing for a clearer view of the maxillary sinuses without obstruction from the petrous ridges. This adjustment ensures that the petrous ridge is positioned below the maxillary sinus floor in the image, thereby providing an optimal view of these structures.

Proper adjustment of head extension is critical in achieving the appropriate imaging results and making precise diagnoses based on the radiographic findings.