How to reliably evaluate middle ear diseases? Comparison of different methods of post-processing based on multislice computed tomography examination.

CONCLUSIONS

Multislice computed tomography (MSCT) virtual endoscopy was useful in evaluating mainly post-traumatic and postoperative cases. In other pathological conditions axial images and MPR reformations were most useful.

OBJECTIVES

Evaluation of cross-sectional images, multiplanar 2-D reformations, 3-D reconstructions and virtual endoscopy (VE) in assessment of the middle ear in inflammatory diseases, trauma, otosclerosis and tumours. Comparison of each method and correlation with surgical findings.

MATERIALS AND METHODS

Investigations were carried out in 80 patients with middle ear pathology. In each case MSCT of the petrous bone was performed. In addition to cross-sectional native scans, frontal and sagittal images were achieved using MPR reconstructions. 3-D volume rendering (VR) and VE images were also generated. The value of native scans information, 2-D, 3-D reconstructions and VE of the tympanic cavity structures was assessed in comparison to intraoperative findings.

RESULTS

MPR reconstructions were most useful in the assessment of skull base trauma, skull base tumours and in cases of chronic middle ear inflammation. Highly vascularized tumours, disruption of ossicular chain and stapes prosthesis were best evaluated on 3-D reconstructions. Axial images proved to be the best for otosclerosis interpretation.