CT EVALUATION OF CONGENITAL AURAL ATRESIA - WHAT THE RADIOLOGIST AND SURGEON NEED TO KNOW

Purpose: The preoperative evaluation of aural atresia and stenosis is strongly dependent upon high resolution CT. We have devised a 10 point surgical rating scale based on high resolution CT of the temporal bon e that will provide radiologists with a stepwise method of evaluating these scans and will allow them to communicate these findings to otolo gic surgeons in a consistent fashion. Method: We prospectively evaluat ed 1,500 patients with aural atresia or stenosis for eight critical ar eas of temporal bone anatomy, each area receiving I rating scale point , with the exception of the presence of a stapes, which received 2 poi nts. The appearance of the external ear received the final point on th e rating scale since the external ear is formed earlier than the middl e ear and helps to predict its deformities. The presurgical score was utilized in selecting surgical candidates and was correlated with the intraoperative findings as well as the postsurgical results by compari ng pre- and postoperative speech reception threshold. Patients with a presurgical rating of less than or equal to 5 were not considered surg ical candidates, Otherwise, the percentage of successful surgeries cor responded roughly to the rating scale. Results and Conclusion: Thus, a presurgical rating of 8 points translates into an 80% chance of resto ring hearing to normal or near-normal levels.