164 THE NASAL ACCESSORY SINUSES IN MAN 



the clinical observations of Dr. Greenfield Sluder, of St. 

 Louis, regarding neuralgias from irritations of the fifth 

 nerve by infectious processes in the sinus sphenoidalis such 

 irritation in some reported instances having first occurred 

 in early childhood. 



In all cases in this series one sinus sphenoidalis was found 

 on each side, and in no instance was more than the one pres- 

 ent. The septum sphenoidale was in all cases complete. 

 The position of the septum was usually vertical and median 

 in the anterior portion, but deviating slightly from these 

 planes posteriorly. In some instances, however, the in- 

 equality in the rate of resorption had been sufficient to pro- 

 duce a more marked deviation of the septum, even to an 

 extent which made the septum form the posteromedial 

 wall of the smaller sinus a process similar to that described 

 when considering deviations of the septum frontale. 



The extent of sphenoidal pneumatization, like that of all 

 other nasal accessory sinuses, may show wide variations in 

 specimens of approximately the same age. The develop- 

 ment during childhood may be slow, as is shown in Figs. 

 32, 34, and 36, and marked deficiency in resorption may 

 persist in adult specimens (Fig. 55). The sinus shown in 

 Fig. 56 may be taken as the form to illustrate approximately 

 the average adult type. In many instances, however, the 

 sinuses not only fill the body of the sphenoid, but may ex- 

 tend far into the clivus, or recesses may develop into the 

 processus pterygoideus (Figs. 45, 47, and 54), into the greater 

 or the lesser wings of the sphenoid, or, in some instances, 

 into the orbital process of the palate bone. (Pneumatiza- 

 tion of the orbital process of the palate bone, however, was 

 found to be more frequently produced by the extension of a 



