Type of sphenoid sinus in the adult population is usually

The types of the sphenoid sinus can be classified in three groups in the adult: I. conchal, II. pre sellar, and III sellar types, depending on the extent to which the sphenoid bone is pneumatized.In the conchal type, the area below the sellar is a solid block of bone without an air cavity.In the pre sellar type, the sphenoid sinus has moderate air cavity with no sellar indentation.In the sellar type, which is the most common, the corpus of the sphenoid is well pneumatized with full indentation of the sellar into the sinus and extends posteriorly until the clivusThe conchal type is most common in children and infrequent in the adult (Rhoton).