Adenomatoid odontogenic tumor: correlation of MRI with histopathological findings.

Adenomatoid odontogenic tumor is a rare benign and odontogenic tumor that is frequently misdiagnosed as other odontogenic cysts and tumors on radiographic examination. To acquire additional information of adenomatoid odontogenic tumor, we performed magnetic resonance imagings (MRI) at a case of adenomatoid odontogenic tumor. The lesion was divided between the peripheral portion with a thick circular shape and the central portion with a round shape on the basis of the signal intensity (SI) of MRI. The peripheral portion showed intermediate SI contained multifocal no SI on T1WI, high SI contained multifocal no SI on T2WI, and heterogeneous enhancement on CE-T1WI. These multifocal areas corresponded to the numerous punctate radiopaque foci shown on computed tomography. The central portion showed homogeneous low SI on T1WI, homogeneous very high SI on T2WI, and no enhancement on CE-T1WI. Macroscopic examination revealed the round shaped lesion included one large cystic space correspondent to the central portion with a clear cystic wall correspondent to the peripheral portion on MRI. The MRI features corresponded to the macroscopic findings of the histopathological examination.