Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study

Braz J Otorhinolaryngol. 2017;83(5):530---535 Brazilian Journal of OTORHINOLARYNGOLOGY www.bjorl.org ORIGINAL ARTICLE Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study夽 Roseli Saraiva Moreira Bittar, Eduardo Setsuo Sato ∗ , Douglas Jósimo Silva Ribeiro, Robinson Koji Tsuji Universidade de São Paulo (USP), Escola de Medicina, Departamento de Otorrinolaringologia, São Paulo, SP, Brazil Received 2 July 2015; accepted 20 June 2016 Available online 31 July 2016 KEYWORDS Cochlear implant; Vestibular function; Preoperative diagnosis Abstract Introduction: Cochlear implants are undeniably an effective method for the recovery of hearing function in patients with hearing loss. Objective: To describe the preoperative vestibular assessment protocol in subjects who will be submitted to cochlear implants. Methods: Our institutional protocol provides the vestibular diagnosis through six simple tests: Romberg and Fukuda tests, assessment for spontaneous nystagmus, Head Impulse Test, evaluation for Head Shaking Nystagmus and caloric test. Results: 21 patients were evaluated with a mean age of 42.75 ± 14.38 years. Only 28% of the sample had all normal test results. The presence of asymmetric vestibular information was documented through the caloric test in 32% of the sample and spontaneous nystagmus was an important clue for the diagnosis. Bilateral vestibular areflexia was present in four subjects, unilateral arreflexia in three and bilateral hyporeflexia in two. The Head Impulse Test was a significant indicator for the diagnosis of areflexia in the tested ear (p = 0.0001). The sensitized Romberg test using a foam pad was able to diagnose severe vestibular function impairment (p = 0.003). Conclusion: The six clinical tests were able to identify the presence or absence of vestibular function and function asymmetry between the ears of the same individual. © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/). 夽 Please cite this article as: Bittar RS, Sato ES, Ribeiro DJ, Tsuji RK. Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study. Braz J Otorhinolaryngol. 2017;83:530---5. ∗ Corresponding author. E-mail: (E.S. Sato). Peer Review under the responsibility of Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. http://dx.doi.org/10.1016/j.bjorl.2016.06.014 1808-8694/© 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Preoperative vestibular assessment protocol of cochlear implant surgery PALAVRAS-CHAVE Implante coclear; Função vestibular; Diagnóstico pré-operatório 531 Protocolo de avaliação vestibular pré-operatória da cirurgia de implante coclear: estudo descritivo analítico Resumo Introdução: Os implantes cocleares (IC) são indiscutivelmente um método eficaz de recuperação da função auditiva de pacientes surdos. Objetivo: Descrever o protocolo de avaliação vestibular pré-operatória em sujeitos que serão submetidos ao IC. Método: Nosso protocolo institucional prevê o diagnóstico vestibular por meio de seis testes simples: testes de Romberg e Fukuda, nistagmo espontâneo, Head Impulse Test, Head Shaking Nistagmus, prova calórica. Resultados: Foram avaliados 21 pacientes com idade média de 42,75 ± 14,38 anos. Apenas 28% da amostra apresentou todos os testes normais. A presença de informação vestibular assimétrica foi documentada pela prova calórica em 32% da amostra e o nistagmo espontâneo mostrou-se pista importante para seu diagnóstico. A arreflexia vestibular bilateral foi diagnosticada em quatro sujeitos; arreflexia unilateral em três e hiporreflexia bilateral em dois. O Head Impulse Test mostrou-se indicador significante (p = 0,0001) para diagnosticar arreflexia da orelha testada. O teste de Romberg sensibilizado em almofada foi capaz de diagnosticar os comprometimentos severos da função vestibular (p = 0,003). Conclusão: Os seis testes clínicos foram capazes de identificar a presença ou não de função vestibular e assimetria da função entre as orelhas de um mesmo indivíduo. © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Publicado por Elsevier Editora Ltda. Este é um artigo Open Access sob uma licença CC BY (http:// creativecommons.org/licenses/by/4.0/). Introduction Cochlear implants (CI) are highly effective devices for recovery of hearing function in individuals with hearing loss and have facilitated integration into social life. The success of post-implant rehabilitation has raised new challenges in both the selection and the planning of the hearing prognosis of subjects undergoing surgery. Although the cochlear system is distinct from the vestibular system, both have identical neural transmission. The benefits of the electrical stimulation of the CI go beyond the auditory pathways and also benefit the vestibular system and postural control.1 Nonetheless, the CI is not without risk to the semicircular canal and otolith function and may impair or suppress vestibular function, especially if there is pre-existing pathology. The prevalence of postoperative dizziness varies widely in the literature and is around 20% in our cases. It usually resolves in approximately 30 days. Some of these patients develop bilateral vestibular areflexia (BVA), which severely reduces patient quality of life.2 Knowledge of vestibular system function before and after CI surgery is important for the satisfactory management of each case. Therefore, we have added vestibular assessment to our outpatient routine prior to CI surgery. Our main goal is to document the existence of vestibular function and possible asymmetries between the ears before surgery. This information can help in the selection of which ear to implant and can assist in the management of any postoperative vestibular symptoms. In adults, preoperative vestibular assessment was designed to be brief and easy to perform, using resources available at any otorhinolaryngology outpatient clinic. The tests used are able to identify both vestibular asymmetry from unilateral lesions as well as bilateral involvement. The protocol was designed to be accessible to services that perform CI surgery but do not always have a neurotological department and research equipment. It is not our intention to speak at length about each vestibular test used, but to provide the reader a quick and convenient method to identify vestibular impairment. Knowledge of vestibular function can indicate the adequate management and prevent undesirable side effects.3,4 Our goal is to describe the preoperative vestibular assessment of adult patients who are cochlear implant candid (...truncated)