Which projection allows for the visualization of all paranasal sinuses?

The lateral projection is the most effective method for visualizing all paranasal sinuses. This projection allows for a clear view of each of the sinuses—frontal, maxillary, ethmoid, and sphenoid—by placing the patient's side against the image receptor. The lateral position helps to differentiate the various sinuses and provides a comprehensive image of their anatomical relationships.

In this view, the frontal sinuses are displayed above the orbits, the maxillary sinuses appear at the level of the teeth, and the ethmoid and sphenoid sinuses can be well-defined, allowing for assessment of any pathological changes. This provides important information about sinus diseases, such as infections, blockages, or structural abnormalities.

Other projections do not provide as complete a view of all paranasal sinuses simultaneously. For instance, the AP projection focuses primarily on the frontal sinuses and can obscure details of the maxillary or other sinuses. The oblique projection is useful in certain situations but does not comprehensively visualize all sinuses. Although the axial projection can demonstrate specific sinuses, it typically presents one sinus well while not adequately showing the others in a single image. Thus, the lateral projection is specifically chosen for its ability to visualize the entire anatomy