The role of preoperative imaging for cochlear implantation in postlingually deafened adults.

BACKGROUND

Preoperative imaging is standard practice for cochlear implant candidacy. Postlingually deafened adults rarely have temporal bone abnormalities that alter management.

OBJECTIVES/HYPOTHESIS: To determine the role of preoperative imaging for cochlear implantation in postlingually deafened adults. We hypothesize that imaging does not alter management in the absence of history or physical examination findings suggestive of an anatomic abnormality.

STUDY

DESIGN

Nested case-control study.

METHODS

We identified postlingually deafened adults with preoperative imaging and cochlear implantation at our institution from 1995 to 2008. Controls had a negative history and normal exam. Cases had suggestive history or exam. Imaging studies and operative records were reviewed.

RESULTS

Approximately 164 patients met inclusion criteria-59 cases and 109 controls. Mean age at onset of hearing loss was 30.4 years (range, 0-73 yr), mean age at onset of deafness was 54.1 years (range, 9-89 yr), and mean age at implantation was 61.5 years (range, 20.6-89.7 yr). Twenty cases (34%) and 17 controls (16%) had abnormal imaging (p = 0.001). Six cases (8.5%) and 2 controls (1.8%) had changes in their management as a result of the imaging findings (p = 0.023). Both control patients had incidentally detected acoustic neuromas, which altered the side of the cochlear implantation. There was a strong association between preoperative history and exam findings and abnormality on imaging (p = 0.007). Abnormalities were 3 times more likely in patients with a positive history or exam (OR = 2.98; 95% CI, 1.36-6.54).

CONCLUSION

In patients with a negative history and examination, imaging rarely alters management. MRI may detect incidental vestibular schwannomas in patients with asymmetric hearing losses.

LEVEL OF EVIDENCE: 3b, Individual case-control study.