Evaluating the Cribriform Plate Dimensions, Frontal Sinus Ostium Sizes and Frontal Sinus Volume with Computed Tomography

Background: More data needed about the variations of the skull base and relationships between the structures which form the skull base and paranasal sinuses to minimize the complications during endoscopic sinus surgery. The aim of this study was to investigate the relationships between Cribriform Plate (CP) dimensions, frontal sinus ostium sizes and frontal sinus volumes. Materials and Methods: We measured the depth and width of the CP, the larger anteroposterior and side-to-side diameter of the frontal sinus ostia and the frontal sinus volumes on Computerized Tomography (CT) images of 120 adult subjects. Results: The mean depth of CP was 8.43 ± 1.62 mm at the right side and 8.48 ± 1.66 at the left side. The mean frontal sinus volumes were 4.83 ± 3.58 cm3 at the right side and 5.09 ± 3.74 cm3 at the left side. There were significantly larger frontal sinus volumes in males (male/female median values: 4.50/3.54 cm3 ; p=0.03). There were significant positive correlations between CP depth, larger side-to-side and anteroposterior diameter of the frontal sinus ostium and frontal sinus volume (p<0.01). There was a significant negative correlation between larger side-to-side diameter of the frontal sinus ostium and CP width (p:0.041). The presence of ipsilateral hyperpneumatized frontal sinus and deep CP should be taken into consideration to avoid iatrogenic injury. In light of our results, surgeons should remember that the frontal recess may be narrow if the CP is wider than 4.5 mm in preoperative evaluation.