Figure 2: CT-scan (coronal plane) of a patient having been subjected to middle meatal antrostomy. “Missed ostium sequence” on the right side leading to persistence of maxillary sinusitis.
a. Neo-ostium of the maxillary sinus in the middle meatus.
b. Preserved, intact uncinate process and persistent obstruction of the natural maxillary sinus ostium due to mucosal edema of the neighbouring mucosa.