Cone beam versus multi-detector computed tomography for detecting hearing loss

Objective To determine whether the diagnostic value of cone-beam computed tomography (CBCT) is equivalent or superior to that of multi-detector computed tomography (MDCT) for the radiological assessment of conductive hearing loss with intact tympanic membrane in adults. Evaluation of inter- and intraobserver variability and measurement of the radiation dosimetry associated with each technique were secondary objectives. Study design Prospective, single-center study. Methods Ten adults were included from April to June 2013. All patients underwent MDCT and CBCT with reconstruction of temporal bones. Two radiologists with ENT experience reviewed the results twice. Diagnostic agreement between MDCT and CBCT and inter- and intraobserver agreement was evaluated with the kappa statistic. Comparisons of dosimetry were evaluated by calculating the ratio of the CT dose index (CTDI) between MDCT and CBCT. Results Diagnostic agreement between MDCT and CBCT was satisfactory (kappa = 0.69). Inter- and intraobserver agreement was also acceptable, and the average ratio of the CTDI of MDCT and CBCT was 4.01. Conclusion CBCT is a reliable method that uses a low dose of radiation to investigate conductive hearing loss with intact tympanic membrane in adults. Its relevance and potential superiority to MDCT in diagnosing middle ear pathologies such as otosclerosis remain to be demonstrated, but the preliminary data are promising.