Reliability of high‐resolution CT scan in diagnosis of ossicular tympanosclerosis

Abstract

Objectives To evaluate the reliability of high‐resolution CT scans (HRCT scans) in the diagnosis of tympanosclerosis and to determine its benefit to predict the post‐surgical hearing outcome based on comparing radiological and surgical findings. Methods A retrospective study at a tertiary institute included 940 ears that underwent tyampanoplasty for chronic suppurative otitis media (CSOM) between January 2013 and March 2017. Preoperative temporal bone HRCT scans were analyzed to check for the prediction of tympanosclerosis and ossicular fixation. Intraoperatively, ossicular chain integrity was checked. Preoperative and postoperative audiometric evaluations using air‐bone gap (ABG) were compared. A postoperative pure‐tone ABG of 20 dB or less was considered as a successful hearing result. Results are compared with historical control groups, the study has been reviewed and approved by the IRB at the medical research center in Hamad Medical Corporation; however, it is a retrospective study so no informed consent was obtained from the patients. Results The study included 940 ears that underwent tympanoplasties due to CSOM, where 238 out of 940 (25.3%) of ears showed tympanosclerosis during tympanoplasty, intraoperatively, tympanosclerosis was localized to the eardrum in 174 of the 238 involved ears (73.1%), A 64 out of 238 (26.9%) of the ears with tympanosclerosis showed ossicular fixation, divided as 45 ears with Incudo‐malleal fixation, 14 ears with stapes fixation, and 5 ears with triple ossicular fixation. HRCT scan of the temporal bone was suggestive of ossicular chain fixation in 79 cases distributed as 55 incudo‐malleal fixations, 19 stapes fixation, and 5 complete ossicular fixations, with a sensitivity of 96.8%, and specificity of 98%. The audiological results were analyzed, with a patient follow‐up after 6 months. Conclusions Our study showed that CT scans when combined with the clinical findings can be an informative guide to otolaryngologists for preoperative evaluation and counseling of tympanosclerosis surgeries.

Air spaces of the temporal bone: a morphometric analysis with clinical implications

“…When TS plaques affect the mobility of the tympanic membrane, they have to be surgically removed. Larem et al presented a high success rate of tympanoplasty in the myringosclerosis ears with a postoperative air-bone gap ≤ 20 dB in 96.5% of cases [29]. As mentioned above, the ossicle chain can also be affected by TS.…”

“…Intratympanic TS most commonly involves silent areas in the middle ear, with ossicular involvement seen in 30%-40% of cases of intratympanic TS [29]. The severity of the impact of TS on hearing is determined primarily by the location and extent of TS plaques [5].…”

“…This involves the removal of TS mass, followed by a reconstruction of the middle ear sound conductive mechanism [43]. In cases of fixation of the incudo-malleal complex, possible treatment may be the removal of the incus and the head of the malleus and the insertion of a partial ossicular replacement prosthesis (PORP) [29]. Surgical interventions when the stapes is fixed are a manner of great controversy.…”

Imaging of Pathologies of the Temporal Bone and Middle Ear: Inflammatory Diseases, Their Mimics and Potential Complications—Pictorial Review

“…Diffuse hyaline formation and calcium deposits can be observed in specimen for histopathology (Figure 11) [57]. For imaging, CT is important and can show thin, tiny calcifications of the ossicular chain and the adjoining ligamenta mallei, the ligamentous incudis superius and posterius, as well as the ligamentum annulare stapedis (Figure 12) [56,58]. The extent can vary greatly from light calcifications to confluent bone-like plates.…”