Anatomical and volumetric analysis of fibro-osseous lesions of the craniofacial skeleton.

Purpose: Our study aimed to provide volumetric data relating to fibro-osseous lesions of the craniofacial skeleton, in order to highlight risk factors due to the different entities, and to guide clinical decisions for jeopardized patients.

Methods: Volumetric measurements of osteomas and ossifying fibromas were performed by applying the open-source software ITK-Snap to cone-beam computed tomography images. DICOM datasets were imported, identified, and delineated using semiautomatic segmentation; this was then verified using manual segmentation. The volumes of the lesions were computed automatically in cubic millimeters using the program. For statistical investigations, descriptive statistics and independent Student t-tests were performed. Additionally, Pearson's correlation was applied as a bivariate analysis. Values of p < 0.05 were considered significant.

Results: 45 patients (11 male and 34 female) were included in this study. The mean volumes were 10.02 ± 18.79 cm for osteomas and 4.80 ± 5.71 cm for ossifying fibromas (p = 0.016). Males (12.81 ± 20.38 cm) presented significantly larger volumes than females (5.43 ± 10.32 cm) (p = 0.042). With regard to shape, morphology, and affection of surrounding anatomical structures, irregular shape (p = 0.001; p = 0.037), multilocular morphology (p = 0.001; p = 0.037), nerve affection (p = 0.001; p = 0.002), tooth affection (p = 0.001; p = 0.594), cortical bone exceedance (p = 0.033; p = 0.001), and clinically visible symptoms (p = 0.004; p = 0.001) were statistically significantly associated with a larger volume of both entities.

Conclusion: Volumetric analysis revealed that osteomas significantly exceeded the mean size of ossifying fibromas, supporting the argument that special attention should be paid to this entity. In cases of difficult histopathological examination, lesions with irregular shape, multilocular morphology, nerve and tooth affection, cortical bone exceedance, and clinically visible symptoms should be considered for close clinico-radiological follow-up, irrespective of the entity.