Referências anatômicas na cirurgia do implante auditivo de tronco cerebral

Abstract

Audi tory brainstem implant (ABI) is an option for deaf patients who do not have the whole auditory pathways preserved. The surgery, because of its anatomical and functional complexity, requires specific training of the surgeon in an anatomy lab. Aim: To study the surgical anatomy of the auditory brainstem implant surgery. Study design: Anatomic study. Material and Method:In the present study, we dissected a fresh cadaver prepared with a dye solution injected into the arteries and intracranial veins. The location of the insertion of the ABI electrode was studied through translabyrinthine access. Results: The surgical technique used for implanting the brainstem electrode is similar to that used in the removal of vestibular schwannoma. The cochlear nucleus complex, comprising ventral and dorsal cochlear nuclei, is the optimal electrode site. The ventral cochlear nucleus is the principal nucleus for transmission of neural impulses from the 8th pair and form the main ascending route of the cochlear nerve. Neither the ventral nor the dorsal nuclei are visible during surgery and their location depends on the identification of adjacent anatomical structures. Conclusion: The region for the implantation of the electrode in the auditory brainstem implant presents anatomical landmarks that allow its easy identification during surgery.

Satisfação e qualidade de vida em usuários de implante auditivo de tronco cerebral

“…This is usually the case of individuals with Neurofibromatosis type 2 (NF-2), malformation or agenesis of cochlear nerves and/or cochlea, as well as in cases of cochlea ossification following meningitis (1)(2)(3)(4) . The ABI allows access to speech and environmental sounds.…”

“…The different speech perception results of ABI users are associated with various reasons, among them the device's setting parameters, aspects related to auditory processing, the position of electrodes in the cochlear nuclei, as well as etiology, the amount of implantable neural elements, and the general state of the central nervous system (2,8) . In the literature, some authors have observed that ABI users reported clinical improvement in quality of life after using the device (3,8) .…”

Implante auditivo de tronco encefálico: revisão de literatura

“…O núcleo coclear ventral é o principal núcleo de transmissão de impulsos neurais do VIII par. Seus axônios formam a principal via ascendente do nervo coclear 8 .…”

“…Tanto o núcleo ventral como o dorsal não são visíveis durante a cirurgia e sua localização depende de identifi cação de estruturas anatômicas adjacentes 8 . A via de acesso escolhida deve ser ampla o sufi ciente para permitir a correta identificação dos parâmetros anatômicos utilizados como referência ao correto posicionamento dos eletrodos.…”

Implante auditivo de tronco encefálico em pacientes com perda auditiva neurossensorial profunda por meningite e ossificação coclear total bilateral

“…As vias cirúrgicas de acesso ao tronco encefálico mais utilizadas são a retrossigmoídea e a translabiríntica (Brito Neto et al, 2005). A via retrolabiríntica ampliada foi descrita em 2012 para a realização do ABI em crianças .…”