What projection demonstrates all paranasal sinuses?

• A. Parietocanthial projection
• B. Lateral projection
• C. Caldwell projection
• D. Occipitofrontal projection

Answer: (B)

The lateral projection is the most effective for demonstrating all paranasal sinuses because it provides a comprehensive view of the anatomical relationships and allows for the visualization of each of the sinuses: the frontal, maxillary, ethmoid, and sphenoid. In this position, the sinuses can be distinctly outlined without superimposition of surrounding structures, making it easier to assess their size, shape, and any potential pathological conditions such as fluid levels or blockage.

The other projection options, while useful for visualizing specific sinuses, do not provide as complete an overview as the lateral projection. For instance, the parietocanthial projection primarily emphasizes the maxillary sinuses, whereas the Caldwell projection focuses on the frontal sinuses but can also demonstrate the ethmoid sinuses at a more limited angle. The occipitofrontal projection is less common and does not effectively showcase all sinuses simultaneously. Thus, it is the lateral projection that stands out as the best choice for a thorough evaluation of the paranasal sinuses.