Estudo anatômico da cóclea para confecção de instrumental para a cirurgia de implante coclear com 2 feixes de eletrodos em cócleas ossificadas Cochlear anatomy study used to design surgical instruments for cochlear implants with two bundles of electrodes in ossified cochleas

A ossificação da cóclea, decorrente principalmente de meningite, impede a inserção completa do implante coclear convencional. Os implantes com 2 feixes de eletrodos mais curtos do que o convencional foram desenvolvidos especialmente para cócleas ossificadas. Porém, durante essa cirurgia há um grande risco de lesão da artéria carótida interna (ACI). Portanto, a medida da profundidade das cocleostomias para inserir os dois feixes de eletrodos aumentaria a segurança desse procedimento. OBJETIVOS: 1) Obter as distâncias entre as cocleostomias e a ACI em ossos temporais de cadáver; 2) Confeccionar instrumento que possa ser usado na cirurgia de implante coclear com 2 feixes de eletrodos. FORMA DE ESTUDO: Experimental prospectivo. MATERIAL E MÉTODO: Em 21 ossos de cadáveres foi realizada: 1) mastoidectomia cavidade aberta; 2) cocleostomias nos giros basal e médio da cóclea; 3) identificação da ACI; 4) medida da distância entre as cocleostomias e a artéria. RESULTADOS: A medida média ± desvio padrão obtida para o túnel superior foi 8,2 ± 1,1mm e para o túnel inferior foi 8,1± 1,3mm. A menor distância encontrada foi 6,5mm para o túnel superior e 6,0mm para o túnel inferior. CONCLUSÃO: Apesar dos parâmetros calculados concluímos que a melhor medida para ser considerada na confecção do instrumento cirúrgico serão as mínimas medidas obtidas em cada um dos giros cocleares, pois é a maneira mais segura para evitar a lesão da ACI, que pode ser fatal.<br>Cochlear ossification, mainly secondary to meningitis, prevents the complete conventional cochlear implant insertion. Implants with two electrode bundles shorter than the conventional ones were specifically developed for ossified cochleas. However, during surgery there is a high risk of damaging the internal carotid artery (ICA). Therefore, measuring cochleostomy depth in order to insert the two electrode bundles would greatly increase the procedure's safety. AIMS: 1) Find the distances between cochleostomies and ICA in cadaver temporal bones. 2) Design an instrument that can be used in cochlear implant surgery to introduce an implant with two bundles of electrodes. STUDY DESIGN: Experimental prospective. MATERIALS AND METHODS: In 21 temporal bones from cadavers we performed: 1) canal wall down mastoidectomy; 2) cochleostomy in the cochlear basal and middle turns; 3) ICA identification; 4) Length determination between the cochleostomies and the artery. RESULTS: the average distance ± standard deviation obtained for the upper tunnel was of 8.2 ± 1.1 mm and for the lower tunnel it was of 8.1± 1.3 mm. The shortest distance found was of 6.5 mm for the upper tunnel and 6.0 mm for the lower tunnel. CONCLUSION: Despite the values calculated, we concluded that the best value to be considered in creating a surgical instrument are the minimum lengths obtained for each one of the cochlear turns, because this is the safest way to avoid damaging the ICA, that can be fatal

Common Childhood Epilepsy Mimics

Unusual movements in children frequently generate concern of underlying seizures from parents and lead to professional review. Stigma associated with epilepsy heightens anxiety and a wish to confirm or exclude the diagnosis as soon as possible. These considerations could lead to a wrong diagnosis of epilepsy being given with unwarranted exposure to medications with potential side effects and cost burden to families. This chapter seeks to provide practitioners in pediatric epilepsy with an exploration of practical differential diagnoses for epilepsy in children, particularly for convulsive seizures. Evaluation of all epilepsy mimics requires a precise and relevant history to help arrive at a diagnosis. Epilepsy mimics across various ages will be reviewed, with the most common differential diagnoses presented first. Examples of common potential epilepsy mimics include benign sleep myoclonus, which is frequently observed in infants and may be a challenge to differentiate from myoclonic seizures in infants. It is a very common phenomenon in pre-term infants with an incidence of 57–132 per 1000 live births. Breath-holding spells among toddlers are common and may be mistaken for epilepsy, as can reflex anoxic seizures. Self-gratification phenomena have been observed from infancy onward and may resemble clonic seizures. Inattention in school-going children is a differential diagnosis for absence seizures and both conditions may co-exist. Stressed or traumatized children may present with non-epileptic psychogenic seizures, as can children with established seizures. Lack of concurrent electrophysiological correlates and absence of stereotypic presentation help differentiate inattention and non-epileptic seizures from childhood epilepsy. Sleep-related activity such as hallucinations, parasomnias, and hypnagogic jerks could also be mistaken for epilepsy in children. Video electroencephalogram (video-EEG) telemetry evaluation is invaluable in such cases. Lack of video-EEG services, simple videos, or EEG studies in resource-poor settings makes diagnosis of epilepsy imitators challenging. The differences between epilepsy and common differential diagnoses for practitioners in resource-limited settings who may lack access to requisite investigative tools will be addressed in the following text. The outcome for most epilepsy mimics is excellent with minimal morbidity and mortality. The potential danger posed by unnecessary medical interventions caused by misdiagnosis of epilepsy makes it imperative that this possibility is minimized