Avaliação por imagem nos candidatos ao implante coclear: correlação radiológico-cirúrgica

Abstract

No pré-operatório da cirurgia de Implante Coclear (IC) o estudo por imagem adquire importância fundamental, proporcionando ao cirurgião segurança na indicação e realização da cirurgia. A avaliação ideal compreende a associação entre Tomografia Computadorizada (TC) e Ressonância Nuclear Magnética (RNM). OBJETIVO: Avaliar a acurácia dos exames de imagem como preditores de possíveis complicações durante o ato cirúrgico. Desenho do Estudo: Corte transversal. MATERIAL E MÉTODOS: Foram avaliados por prontuários, 104 pacientes submetidos à cirurgia de IC de maio de 2003 a outubro de 2006. Estes passaram por uma seleção multidisciplinar pré-operatória, e radiológica por TC associada ou não à RNM. RESULTADOS: Excluiu-se 4 pacientes sem registro de exames radiológicos, resultando 100 pacientes. Estes foram divididos em dois grupos: grupo A (TC) apresentou acurácia 69,69%, sensibilidade 36,36%; especificidade 86,36%; Valor Preditivo Positivo (VPP) 57,14%; Valor Preditivo Negativo (VPN) 73,07% e o B (TC e RNM) acurácia 80,59%, sensibilidade 38,46%; especificidade 90,74%; VPP 50,0%; VPN 85,96%. CONCLUSÕES: A avaliação radiológica pré-operatória do IC mostrou-se importante, sendo capaz de identificar alterações anatômicas, evitando, ou ao menos, preparando o cirurgião para possíveis complicações. Esse estudo demonstrou que a avaliação associada com TC e RNM pôde ser considerada superior à TC isoladamente.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.