What is the primary goal of the parietocanthial projection?

• A. To visualize the nasal cavity
• B. To demonstrate the zygomatic arches
• C. To project the petrous pyramids below the maxillary sinuses
• D. To capture the frontal sinuses

Answer: (C)

The primary goal of the parietocanthial projection, commonly known as the Waters view, is to project the petrous pyramids below the maxillary sinuses. This positioning allows for a clear visualization of the maxillary sinuses, which can be critical in diagnosing sinusitis or other sinus-related conditions. By angling the X-ray beam correctly, the petrous ridges—part of the temporal bones—are positioned inferiorly to the maxillary sinuses, facilitating a clearer view of both the maxilla and the surrounding structures.

This projection is particularly useful in head and facial imaging as it helps to prevent superimposition of vital anatomical structures. As a result, this technique not only enhances the visualization of the maxillary sinuses but also assists in assessing other surrounding areas of the facial anatomy, making it essential in radiographic examinations of the skull and facial bones.