The causes of hearing loss detected on temporal bone MDCT

Abstract

Objective: Description the findings on temporal bone MDCT scan and diagnostic the causes of hearing loss.
Methods: From 01/2022 to 01/2024, more than 300 patients have been done temporal bone MDCT scan in Diagnostic Imaging Department of Vinmec Healthcare System, of which 250 patients had symptoms of hearing loss, which can be the main or an accompanying symptom. We interpreted the CT findings and diagnostic causes of hearing loss based on the consensus of clinical and imaging diagnostic results, some of which are accompanied by surgical assessment or follow-up examination after treatment.
Results: The patients undergoing temporal bone MDCT scan have F/M ratio 132/118 with an age range from 2 years old to 81 years old. Most type of hearing loss are conductive, with a few being mixed and
sensorineural types. CT findings show that the main cause of hearing loss is otitis media with or without perforated eardrum. Other less common causes including: ear wax, perforated eardrum due to trauma, otosclerosis, middle ear cholesteatoma, external ear cholesteatoma, external ear polyps, ossicular chain abnormalities, tympanic glomus tumor, inner ear malformation, a few cases with normal findings on CT scan in patients diagnosed with nasopharyngitis with eustachian tube obstruction, disorders circulation in the inner ear, or age – related hearing loss,... In cases of otitis media, there is a special case where the cause is tuberculosis in a patient with history of colon tuberculosis and lymph node tuberculosis. In some cases of sensorineural hearing loss or suspected inner ear abnormalities, inner ear MRI was performed to better evaluate the inner ear and especially the vestibular-cochlear nerve. CT scan of the temporal bone has high positive and negative diagnostic value in determining the location of abnormalities and the causes of hearing loss.
Conclusion: MDCT of the temporal bone is a highly valuable method in assessing the morphology of the ossicles, the mastoid cells, tympanic cavity, footplate and inner ear morphology, contributing to the
prediction the causes of hearing loss and other symptoms associated with hearing loss (may be primary or secondary symptoms). The findings are analyzed from the outer ear to the middle ear and the inner ear, depending
on the cause of hearing loss, which has different findings.