CT Scan for Diagnosis of Congenital Atresia of the External Auditory Canal and Other Associated Abnormalities of the Affected Ear

Objective To analyze the CT scan signs of the congenital abnormalities of the external auditory canal of 12 patients, providing the credible results of images for clinic treatment.Methods The CT scan signs of the affected ears of 12 patients(9 boys and 3 girls) were retrospectively analyzed. The mean ages was 22 months(range 1 month~6 years). CT scans were taken by a systemic spiral CT machine for entire temperal bones of the affected sides. The layer thickness of the scan was 1mm and the interval length between the two successive layers was also 1mm.Results Forteen ears of congenital atresia of external auditory canal were approved by CT scan and 7 canals were replaced by bony masses(thickness1mm in 3 ears and 1mm in 4 ears).Thread-like stenosis was found in 5 ears.Canals were blocked by soft tissue in 1 ear and anterior wall defect of the canal in 1 ear. The associated abnormalities of the middle ear,such as following:stricture of tympanic cavity in 10 ears, deformity of atticus in 5 ears and small size with abnormal shape of malleus and incus in 8 ears were also delineated. No obvious abnormality was found in inner ear.Conclusion HRCT could demonstrate patterns and severity accurately, which has already become a indispensable imaging modality for microscopical operation of otology.