em /em Background . em Outcomes /em . From the 140 edges NVP-BEZ235 cost analyzed, 126 (90%) acquired agger nasi and 110 (78.571%) had frontal cells. 37 frontal sinuses had been free from mucosal disease, 48 were opacified partly, and 50 had been totally opacified. There was no significant difference found in frontal sinus mucosal disease in presence or absence of frontal cells or agger nasi. em Conclusions /em . The current study shows that frontal cells might be underreported in the literature, as the prevalence identified is usually noticeably higher than previous studies. 1. Introduction Functional endoscopic sinus surgery (FESS) has become one of the commonest surgical procedures performed by otolaryngologists . The widespread adoption of FESS has improved the understanding of the anatomy of the nose and the paranasal sinuses. However, the area which still causes confusion to surgeons is the frontal recess . Medical procedures in this area is usually challenging due to its narrow confines and variable anatomy . Anatomically, the frontal recess is usually bounded medially by the middle turbinate and laterally by the lamina papyracea . The posterior wall of the frontal recess is the bulla lamella. If the latter does not reach the skull base, the frontal recess may open into the suprabullar recess. The anterior wall is formed by the frontal process of the maxilla and the frontal bone, which thickens anterosuperiorly to form the frontal beak. In the posteromedial and superior region of the frontal recess lies the lateral wall of the olfactory fossa, which is the thinnest part of the anterior skull base . This interesting anatomical area was described by Schaeffer in 1916 as the nasofrontal region . However, the first detailed description of the various cells in this area was in 1941 by van Alyea , who used the term frontal recess rather than nasofrontal duct. Van Alyea used the name frontal cells in its broader meaning to refer to the different types of ethmoidal cells pneumatizing in this area. This included the frontal cells (sometimes called the frontoethmoidal cells), as described by Kuhn et al. , the agger nasi cells, the interfrontal sinus septal cells, and the supraorbital cells. Other cells which have also been described in this area include the suprabullar cells and the frontal bulla cells . The agger nasi is generally considered to be the most constant cell in the frontal recess and was found by Bolger et al.  to exist in 98.5% of patients. The term frontal cells (frontoethmoidal cells) is currently used to describe a group of anterior ethmoidal cells that have been classified by Kuhn et al.  into 4 types. Type I is usually a single frontal cell above an agger nasi cell. Type II is usually a tier of cells in the frontal recess above the agger nasi cell. Type III is usually a large cell pneumatizing from the frontal recess into the frontal sinus. Type IV is usually a cell totally isolated within the frontal sinus. Frontal cells have been reported to occur in 20C41% of paranasal sinuses . In our practice, we noticed that reviewing the CT scans of patients admitted for FESS revealed the presence of frontal cells more often than not. Our impression was that the frontal cells might be underreported in the literature. 2. Methods Coronal and axial CT paranasal sinuses scans of 70 consecutive patients admitted for FESS from November 2007 to January 2009 were reviewed as a part NVP-BEZ235 cost of an audit of FESS techniques in our department. The scans were studied to identify the agger nasi and the frontal cells as classified by Kuhn et al. . The cells were identified on the right and left sides separately. Ipsilateral frontal sinus mucosal disease was detected and scored according to the Lund and Mackay system . Other types of frontal recess cells like interfrontal sinus septal cells, supraorbital cells, suprabullar cells, and frontal bulla cells were not included in this study. Fisher’s Mouse monoclonal to ABCG2 NVP-BEZ235 cost exact test and chi-square test with Yates’ correction for tables with 1 degree of freedom were used to test the statistical significance of.