How Efficacious is HRCT Temporal Bone in Determining the Ossicular Erosion in Cases of Safe and Limited Squamous Type CSOM?

HRCT temporal bone is a very valuable radiological investigation. However its still not widely used by otologists for routine surgeries. Ossicular erosion is often encountered unexpectedly in safe cases of CSOM and in limited squamous type of cases. If preoperative diagnosis of ossicular erosion is made then otologist can preoperatively plan ossicular reconstruction techniques leading to improved results. We conducted a study in 60 patients to evaluate the efficacy of HRCT temporal bone in determining ossicular erosion in cases of CSOM. It was a diagnostic observational study where surgical finding of ossicular erosion was taken as a gold standard. Sensitivity specificity; positive predictive value and negative predictive value of HRCT was calculated in detecting malleus; incus and stapes erosion. P value was calculated. Sensitivity and specificity for malleus erosion was 78.5% and 78.1% respectively. Sensitivity and specificity for incus erosion was 73.1% and 57.8% respectively. Sensitivity and specificity for stapes erosion was 52% and 57.1% respectively. P value was less than 0.05. We concluded that HRCT is a good adjunct for determining the ossicular erosion and its use should be encouraged by the otologist.