Radio-surgical correlation of chronic suppurative otitis media

Abstract

Background: Chronic suppurative otitis media (CSOM) because of disease nature and location of vital structures like middle ear ossicles, facial nerve, and lateral semicircular canal poses clinical as well as radiological challenge in diagnosis, especially the squamosal variety. Hence this study to evaluate radio-surgical correlation in cases of CSOM.

Methods: We retrospectively analysed 92 case records who met the inclusion criteria. Their pre-operative high-resolution computed tomography (HRCT) temporal bone imaging was evaluated for erosion of the ossicular chain and the fallopian canal. This was correlated with the surgical findings noted intra-operatively. The appropriate statistical analysis was carried out. The radio-surgical correlation was evaluated by Cohen’s kappa value.  

Results: The kappa value for status of ossicular chain was 0.805 and 0.384 for status of fallopian canal. HRCT imaging had a positive predictive value and negative predictive value of 94.3% and 85.3% respectively, in detecting ossicular chain erosion. In detecting fallopian canal erosion, HRCT showed a sensitivity of 33.3%. Analysing the individual ossicles, we found kappa to be 0.266 for malleus, 0.463 for incus and 0.827 for stapes.

Conclusions: There was excellent radio-surgical correlation for ossicular chain erosion while it was poor for fallopian canal erosion. HRCT showed excellent radio-surgical correlation for stapes, moderate for incus and poor for malleus. In-spite of its shortcomings in differentiating cholesteatoma and non-cholesteatomatous pathologies of the middle ear cleft, HRCT imaging plays a key role in assessing the status of the ossicles and fallopian canal.