Preoperative Evaluation of Bone Destruction Using Three-dimensional Computed Tomography in the Temporal Bone with Cholesteatoma

Jang, Chul Ho; Lee, Jin Su

Abstract

BACKGROUND AND OBJECTIVES: Conventional two dimensinnal computed tomography (2DCT) may provide precise details of soft tissues and bony structures of the temporal bone, but does not make an impression of direct visulaization of the lesions. The present study is to investigate the usefulness of three dimensional CT (3DCT) studies in the evaluation of bony defects caused by cholesteatoma.
MATERIALS AND METHODS
Fifteen cholesteatoma patients who showed bony destruction or suspicious destruction in the 2DCT were examined using 3DCT, The examination was carried out in axial or coronal planes with the technical factors of 125 kV, 200 mA, 1 mm thickness, and scanning time of 1 second. The CT data was transferred to a workstation with a real-time image processor. We used a software (solaris Adw 1.2, Sun co. USA) enabling image processing. The threshold-based imaging was used for 3D reconstruction.
RESULTS
In all patients, 3DCT clearly delineated the destruction of bony structures by cholesteatoma, The 3DCT generated images did provide spatial relationships which were not easily appreciated on 2DCT. Intraoperative bony destniction findings were correlated with 3DCT.
CONCLUSION
The 3DCT could be useful to evaluate the invasiveness of cholesteatoma to the cranial base. It would be also helpful in planning to reconstruct during surgery.