Multiplanar computed tomographic analysis of the frontal recess region in Chinese subjects without frontal sinus disease symptoms.

The purposes of this study were to determine the prevalence of frontal-ethmoidal cells and to evaluate variation in the superior attachment of the uncinate process in Chinese subjects. 202 normal Chinese subjects (404 sides) underwent spiral computed tomography and multiplanar reconstruction images were evaluated. Agger nasi cells showed a prevalence of 94.1%. Of all the frontal cells identified in 159 sides (39.6%) of frontal recesses, the prevalence of type I, type II and type III cells was 24.4, 7.0 and 8.2%, respectively. Suprabullar, frontal bullar and interfrontal septal cells were identified in 148 sides (36.6%), 36 sides (9.0%) and 25 subjects (12.4%), respectively. 244 uncinate processes (60.4%) had 1 superior attachment and the remainder (39.6%) had 2 superior attachments. The prevalence of terminal recesses was 89.1%. Our results characterized normal frontal recess pneumatization patterns in Chinese subjects. That, together with variation in the superior attachment of the uncinate process, emphasized the role of agger nasi cells and the uncinate process in endoscopic frontal sinus surgery.