Figure 1. Coronal CT of the sinus at 50 mAs. In the left paranasal sinus the uncinate process (open arrow), infundibulum (double headed arrow) and maxillary ostium (large arrow) are clearly seen, i.e. scoring 2 for each structure. In the right paranasal sinus the infundibulum (double headed arrow) and uncinate process (open arrow) are demonstrated but not clearly visualized, i.e. scoring 1 each.