Volumetric evaluation of the paranasal sinuses in normal subjects using computer tomography images: a stereological study.

Objective: The size and shape of paranasal sinuses are especially relevant when considering endoscopic sinus surgery. For this reason, the size of the paranasal sinuses has been the subject of manystudies, none of which has used stereological methods to estimate thevolume.In the present stereological study, we estimated the volume of paranasal sinuses of normal males and females. Material and methods: We used a combination of the Cavalieri principle and computer tomography scans taken from 39 male and 38 female patients to estimate the volumes of frontal, maxillary, ethmoidal and sphenoidal sinuses. Results: The mean volumes of frontal, maxillary, ethmoidal and sphenoidal sinuses were estimated bilaterally, producing mean volumes of 11.6 � 0.8, 35.9 � 1.3, 11.8 � 0.4 and 13.6 � 0.7 cm 3 , respectively. When the correlations between estimated volumes were analyzed statistically a positive relation was found for the paranasal sinuses. The size of the sinuses tends to decrease with age. Conclusion: The findings of the present study using the stereological methods could provide data for the evaluation of normal and pathological volumes of the paranasal sinuses. # 2006 Elsevier Ireland Ltd. All rights reserved.