Imaging study of ossifying fibroma with associated aneurysmal bone cyst in the paranasal sinus

• Published in: European journal of radiology 2012-11, Vol.81 (11), p.3450-3455
• Main Authors: Yang, B.T, Wang, Y.Z, Wang, X.Y, Wang, Z.C
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aneurysmal bone cyst; Bone Cysts, Aneurysmal - complications; Bone Cysts, Aneurysmal - diagnosis; Bone Neoplasms - complications; Bone Neoplasms - diagnosis; Child, Preschool; Female; Fibroma, Ossifying - complications; Fibroma, Ossifying - diagnosis; Humans; Magnetic Resonance Imaging - methods; Male; Middle Aged; MR imaging; Ossifying fibroma; Paranasal Sinus Neoplasms - complications; Paranasal Sinus Neoplasms - diagnosis; Radiology; Reproducibility of Results; Sensitivity and Specificity; Sinonasal cavity; Tomography, X-Ray Computed - methods; Young Adult
• ISSN: 0720-048X; 1872-7727
• DOI: 10.1016/j.ejrad.2012.05.010

Abstract Objective To determine the CT and MR imaging features of ossifying fibroma with aneurysmal bone cyst of the paranasal sinus. Materials and methods We retrospectively reviewed 15 patients with histopathology-proven ossifying fibromas with aneurysmal bone cysts in the paranasal sinus. All 15 patients underwent CT and MR imaging. The following imaging features were reviewed: location, shape, margin, CT findings, and MR imaging appearances and time-intensity curve of dynamic contrast-enhanced MR imaging. Results Ossifying fibromas occurred in the maxillary sinus in one patient, sphenoid sinus in 2, frontal sinus in 3, frontoethmoid sinuses in 3, and ethmoid sinus in 6 patients. Ossifying fibromas showed an elliptic-shape and aneurysmal bone cysts revealed a multicystic appearance, with well-demarcated margins. On unenhanced CT, ossifying fibromas appeared isodense to gray matter with scattered calcifications in nine, ground-glass appearance in 6 patients and aneurysmal bone cysts showed mixed density. Ossifying fibromas appeared isointense to gray matter in 12 and slightly hypointense in three patients on T1-weighted images, and isointense in 4 and hypointense in eleven patients on T2-weighted images, with moderate or marked enhancement after administration of contrast material. The time-intensity curves of eight ossifying fibromas exhibited a rapidly enhancing and rapid washout pattern. The intracystic components of aneurysmal bone cysts showed heterogeneous signal intensity on MR images, with fluid–fluid levels identified clearly by T2-weighted images, without enhancement. The periphery and septa of aneurysmal bone cysts appeared isointense on MR images, with marked enhancement. Conclusions Fluid–fluid levels within an elliptic-shape mass with scattered calcifications or ground-glass appearance is highly suggestive of this complicated entity in the paranasal sinus.