[Computed tomographic diagnosis of postoperative maxillary cyst (POMC)--a comparison with conventional tomography]

We reviewed the computed tomographic (CT) findings of postoperative maxillary cyst (POMC) in 64 patients with 79 lesions, and evaluated its diagnostic efficacy. Typical CT finding of POMC was an expansile and homogeneous soft tissue mass with bone erosion. Thin-walled capsule and bony septation were also demonstrated in 72% and 35% of the lesions, respectively. A comparison between conventional tomography and CT has been made in the same subjects for evaluation of the detectability and extension diagnosis of POMC. CT proved to be superior to conventional tomography in diagnosing the presence and the extent of POMC. We conclude that conventional tomography is not necessary in diagnosis of POMC, when full examination of the paranasal sinus is performed by CT.