Anatomic Variations of the Frontoethmoidal Region according to the International Frontal Sinus Anatomy Classification (IFAC) and Radiological Sings of Sinusitis

Introduction:

The endonasal approach to the frontal recess and sinus can be complicated by a variety of anatomical variants. The intention of this study was to analyze the incidence of anatomical variants of the paranasal sinuses according to the International Frontal Sinus Anatomy Classification (IFAC) and to show the incidence of radiological signs of opacification.

Material and methods:

249 CT data sets of the nasal sinuses were analyzed in multiplanar reconstructions. Exclusion criteria were previous surgical procedures of the paranasal sinuses, oncological diseases of the paranasal sinuses and insufficient image quality that prevents a correct analysis. All anatomical variants were analyzed according to the IFAC criteria. Radiological signs of opacification were classified according to the Lund-Mackay staging system.

Results:

The analysis revealed Supra Agger cells (SACs) in 48% and Supra Agger frontal cells (SAFCs) in 25% of the data sets. Suprabulla cells (SBCs) could be identified in 88%, Suprabulla frontal cells (SBFCs) in 26% of the CTs. Even in anatomical variants, which extended far into the frontal sinus, the incidence of radiological sings of opacifications was not higher compared to “normal” anatomic conditions.

Conclusion:

Anatomical variants of the fronto-ethmoidal region are frequent. In 43% of the data sets cells – according to the IFAC criteria – with pneumatization close to or into the sinus frontalis could be observed. Obviously, even large cell formations do not necessarily prevent mucus drainage and ventilation of the paranasal sinuses. Surgical interventions at the frontal recess and sinus should therefore only be planned in specific complaints and corresponding diagnostic findings.

Publication History

Publication Date:
18 April 2018 (online)