110 THE NASAL ACCESSORY SINUSES IN MAN 



as found in cases of different ages, are given in the above 

 table of measurements of the sinus maxillares. The rela- 

 tions of the ostium to the infundibulum are fairly constant. 

 The opening is in the inferolateral wall of the infundibulum, 

 the situation of the midpoint of the ostium corresponding 

 approximately to the anterior portion of the middle third 

 of the infundibulum. 



Communication between the sinus maxillaris and the 

 meatus medius is via the ostium maxillare, the infundibulum 

 ethmoidale, and the hiatus semilunaris (Figs. 26, 37, and 

 53). The distance between the ostium maxillare and the 

 hiatus semilunaris varies in adult cases from 4 to 12 mm., 

 according to the width of the processus uncinatus and also 

 to the degree of the medial inclination of its free or postero- 

 superior portion. 



Through the anterior portion of the infundibulum the 

 sinus maxillaris is brought into close relationship with the 

 cellulse infundibulares, and to all sinus frontales having their 

 ostia lateral to the processus uncinatus (Figs. 35, 49, and 

 52). In this series the ostia of 39.6 per cent, of the frontal 

 sinuses were so located. These relations are important 

 when dealing with suppurative conditions in this area; also, 

 as observed by Keen, in those cases of sarcoma of the maxilla 

 in which a portion of the growth has extended toward or 

 into the frontal region, partially or completely filling the 

 infundibulum, the cellule infundibulares, or even the sinus 

 frontalis. 



Duplication of the ostium maxillare is a condition in which 

 the sinus maxillaris has two ostia, both of which communicate 

 with the infundibulum ethmoidale. Such a condition was 

 present in only one specimen in this series (Fig. 54) . Dupli- 



