PNEUMATIZATION OF THE ANTERIOR CLINOID PROCESS OF THE SPHENOID BONE

A CLINICO- ROENTGENOGRAPHIC STUDY

Abstract

Lateral skull x-ray films of 29 bleached skull specimens and of 1, 000 clinical cases were examined carefully for any degree of pneumatization of the anterior clinoid process of the sphenoid bone.
Some degree of pneumatization of the clinoid process was discerned in approximately one-third of the cases. Generally, the degree of pneumatization was more pronounced in those that showed greater development of the sphenoid sinus. In these cases the roof of the lesser wings of the sphenoid was elevated and protruded into the cranial cavity.
The appearance of the Eminentia optica on the postero-superior wall of the extreme posterior sinuses coincided closely with the degree of pneumatization of the clinoid process in the skull specimens. The x-ray findings in the clinical cases, however, were not always consistent with the operative findings in this respect, probably due to inadequate visualization of this region during operation or to unsatisfactory x-ray films for detection of any extension of pneumatization into the clinoid process.
Careful x-ray examination of the skull for any sign of pneumatization of the anterior clinoid process of the sphenoid bone preoperatively might therefore provide information concerning the degree of intrasinus projection of the optic nerve canal and help to prevent injury to the optic nerve during operation of the extreme posterior sinuses.