Development of Paranasal and Mastoid Sinuses: A Computed Tomographic Pilot Study

Abstract

Paranasal sinus and mastoid disease in children is an important potential source of intracranial sepsis. Cranial computed tomographic (CT) scans are a primary imaging modality for assessment of the paranasal sinuses and mastoids. Radiographic assessment of paranasal sinus development has largely been confined to plain radiographs and polytomographic examination. We report a pilot, quantitative analysis of 30 CT scans obtained from patients without known ear, nose, or throat disease, and aged from 3 weeks to 13.8 years. Ethmoid, sphenoid, and mastoid sinus development was assessed by a "pneumatization index" (PI) derived from each CT scan. At all ages, the rank order of sinus development was ethmoid > mastoid > sphenoid. Individual developmental rates showed considerable variation. In the newborn, mastoid and sphenoid sinus development was minimal, whereas ethmoid sinuses showed substantial aeration. The data suggest that, for children older than 5 years of age, an ethmoid sinus PI ≤ 0.714 is highly suspicious of paranasal sinus disease. (J Child Neurol 1986; 1:46-49)