Usefulness of cone-beam CT for presurgical assessment of keratoma (cholesteatoma) of the maxillary sinus.

BACKGROUND Evaluating the presurgical usefulness of cone-beam CT (CBCT) in the diagnosis and subsequent surgery of keratoma (cholesteatoma) of the maxillary sinus. METHODS CBCT scans were obtained by using 3-dimensional CT (3DCT) apparatus. The exposure factors had a field of view of 16 × 12 cm, 120 kVp, 7 mA, and an exposure time of 20 seconds. The acquired image data consisted of a 14-bit sensor that delivers 16,384 shades of gray with a standard isotropic cubic voxel size of 0.3 mm. RESULTS The CBCT scans clearly demonstrated a 22- × 16.82- × 17.62-mm expansile lesion in the left maxillary sinus area, with thin cortical plates, and a focal perforation of the medial cortical plate at the level of the apices. CONCLUSION All CBCT visual data provide impressive, full 3D images of maxillary sinus keratoma, and help us to perform successful surgery.