The obstruction was caused by agger nasi cells in 6 (43%), ethmoidal bulla or accessory cells in 4 (28.
Table 2: Middle Turbinate Variations Variation Number Percentage Typical 25 50 Paradoxically curved 6 12 Pneumatized 17 34 Large non-pneumatized 2 4 Table 3: Uncinate Superior Attachment Attachment Number Percentage Middle turbinate 21 42 Lamina papyracea 18 36 Skull base 11 22 Table 4: Ethmoidal Bulla Variations Typical 31 62 Large 11 22 Hypoplastic 8 16 Table 5: Correlation of Diagnostic Endoscopy Finding with Computed Tomography Findings Sl.
Laine & Smoker (14) have defined the osteomeatal complex as an aerated channel of the middle meatus representing the final common pathway for drainage of the maxillary and frontal sinuses and anterior ethmoid cells, delimited by the uncinate process, ethmoidal bulla and middle turbinate.
ENLARGED ETHMOID BULLA: An enlarged ethmoidal bulla may obstruct the infundibulum or the middle meatus.
The more common variations can be divided into four groups, depending on the structures involved: middle turbinate bone, uncinate process, ethmoidal bulla and nasal septum.
Ethmoidal Variations: Haller cells-According to Kennedy and Zinreich (17), Haller cells, ethmoidal air cells that project inferiorly to the ethmoidal bulla into the floor of the orbit in the region of the maxillary sinus ostium, are encountered in 10% of the population (Figure 5).
The ethmoidal bulla can be so extensively pneumatized that it completely fills the sinus of the middle turbinate bone (Figure 6).
Among the anatomic variants, concha bullosa (especially the larger ones), and giant ethmoidal bulla occur in the vicinity of maxillary sinus infundibulum, and agger nasi cells are close to the frontal sinus recess.