Transport through the maxillary ostium in the ethmoid infundibulum

The aim of this study was to use transnasal endoscopy to observe transport through the maxillary ostia in the ethmoid infundibulum, to gain more basic scientific information about the nasal cavity and paranasal sinus.

Transnasal observation of 512 patients in a supine or seated position was conducted with 0- and 70-degree nasal endoscopes. Drainage pathways of mucopurulence at the natural maxillary ostia were observed. A dye test was also performed in 53 patients to clearly observe real-time transport of activated carbon in the ethmoid infundibulum.

Among 914 ethmoid infundibula, mucopurulence and activated carbon were transported out of 31 and 53 natural maxillary ostia, respectively. All ethmoid infundibula drained at the inferior edges of the ostium, despite patients' supine or seated positions. Fourteen cases of mucopurulence and 17 cases of activated carbon flowed circularly in the ethmoid infundibula. The flow of activated carbon from the natural ostium to the nasopharynx could also be observed simultaneously or solely. However, there were 6 ostia through which no activated carbon flowed back into or drained out of the sinus, despite flow from the natural ostium to the nasopharynx or circular flow.

The drainage pathway of the maxillary ostium is its inferior edge. The accessory ostium is only necessary to promote circular flow. Mucopurulence or activated carbon, which flowed circularly in the ethmoid infundibulum, can also be gradually transported to the nasopharynx. Revision surgery may not be necessary for all patients with circular chronic maxillary sinuses.