Evaluation by imaging methods of cochlear implant candidates: radiological and surgical correlation

Evaluation by imaging methods is critical in the preoperative care of cochlear implant (CI) surgery, providing safety to surgeons when indicating and performing this procedure. The ideal imaging study consists of an association between Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). AIM: To investigate the accuracy of imaging studies as predictors of possible complications of surgery. Study Design: A cross-sectional investigation. MATERIAL AND METHOD: The medical records of 104 patients undergoing CI surgery between May 2003 and October 2006 were studied. The preoperative muldisciplinary selection process included CT associated or not with MRI. RESULTS: The final sample was composed of 100 patients after 4 patients with no records of radiological exams were excluded. Patients were divided into two groups. The accuracy of group A (CT only) was 69.69%, the sensitivity was 36.36%, the specificity was 86.36%, the Positive Predictive Value (PPV) was 57.14%, and the Negative Predictive Value (NPV) was 73.07%; the accuracy of group B (CT and MRI) was 80.59%, the sensitivity was 38.46%, the specificity was 90.74%, the PPV was 50.0%, and the NPV was 85.96%. CONCLUSION: The preoperative radiological evaluation by CI was effective in identifying anatomic abnormalities, allowing surgeons to avoid, or at least be aware of, possible complications. This study demonstrated that CT and MRI were superior to CT alone.