Cochlear Implant Surgery: Endomeatal Approach versus Posterior Tympanotomy.

The aim of the present study was to compare the posterior tympanotomy (PT) technique to the endomeatal approach. The endomeatal approach (EMA) for Cochlear Implant (CI) surgery was performed on 98 patients with procident lateral sinus or a small mastoid cavity, on 103 ears (Group A). Conventional mastoidectomy and PT was performed on the other 104 patients, on 107 ears (Group B). Data on all patients were then collected for the following: intra- and post-operative complications, Tinnitus Handicap Inventory (THI), Vertigo Symptom Scale (VSS), duration of surgery, and postoperative discomfort. The difference in the total number of major and minor complications between the case group and the control group was not statistically significant. There was a statistically significant difference in discomfort between the two groups using the Visual Analogue Scale (VAS), both immediately postsurgery (p = 0.02) and after one month (p = 0.04). The mean duration of surgery was 102 ± 29 min for EMA and 118 ± 15 min for the PT technique (p = 0.008). EMA is a faster technique resulting in reduced postoperative patient discomfort in comparison to the PT method. The experience of the surgeon as well as the correct choice of surgical technique are fundamental to successful outcomes for cochlear implant surgery.

Comparación de complicaciones según la técnica utilizada en los implantes cocleares / Comparison of complications by technique used in cochlear implants

Introducción: Las complicaciones son un indicador muy sensible de la utilidad de una técnica quirúrgica. En cirugía de implante coclear se pueden utilizar 3 abordajes: el abordaje clásico utiliza el receso facial (RF) para el paso del electrodo; el abordaje suprameatal (SMA) no requiere mastoidectomía y utiliza la creación de un túnel que pasa por encima del nervio facial para entrar a la caja del tímpano desde atrás, y el abordaje endomeatal (EMA) que se basa en la realización de un canal en la pared posterior del conducto auditivo externo. Material y métodos: Estudio multicéntrico de revisión de 208 pacientes, comparando las diferentes técnicas de abordaje descritas. Se clasificaron las complicaciones en mayores y menores. Resultados: Entre los 208 pacientes implantados el 10,5% (22 de 208) presentó complicaciones, de estas el 2,88% (6 de 208) fueron complicaciones mayores que llevaron a la reimplantación y el 7,69% (16 de 208) fueron complicaciones menores. Comparando los resultados obtenidos por los diferentes grupos, podemos decir que la técnica del RF es la que menos porcentaje de complicaciones mayores tuvo, 1,1% seguida de la técnica EMA con un 2,38% y la SMA con un 3,75%. En cuanto a las complicaciones menores, el grupo operado por SMA tuvo el menor porcentaje presentando el 6,25%, seguido del grupo operado por EMA con el 7,14% y el grupo operado por el RF presentó el 10%. Conclusiones: Las 3 técnicas quirúrgicas descritas muestran un porcentaje de complicaciones muy similar. Por lo tanto, podemos concluir, que las 3 técnicas son seguras y alternativas unas con otras (AU)

Introduction: Complications are a very sensitive indicator of the usefulness of a surgical technique. In cochlear implant surgery, there are 3 principal approaches: the classic approach uses the facial recess (FR), the suprameatal approach (SMA) does not require mastoidectomy and uses the creation of a tunnel over the facial nerve to enter the middle ear, and the endomeatal approach (EMA) is based on the completion of a groove in the posterior wall of external auditory canal. Material and methods: A multicentre review of 208 patients with cochlear implants, comparing the different techniques. The complications were classified into major and minor. Results: Among the 208 implanted patients, 10.5% (22 of 208) had complications. Of these, 2.88% (6 of 208) were major complications and 7.69% (16 of 208) were minor complications. Comparing the results obtained by the different approaches, the FR technique had the lowest rate of major complications (1.1%), followed by the EMA technique with 2.38% and SMA with3.75%. As for minor complications, operations in the SMA group had the lowest rate (6.25%), followed by the EMA group (7.14%) and the group operated on using the FR technique presented the highest (10%).Conclusions: The 3 techniques described show very similar rates of complications. Consequently, we can conclude that they are safe and are alternatives (AU)

Comparison of complications by technique used in cochlear implants.

INTRODUCTION: Complications are a very sensitive indicator of the usefulness of a surgical technique. In cochlear implant surgery, there are 3 principal approaches: the classic approach uses the facial recess (FR), the suprameatal approach (SMA) does not require mastoidectomy and uses the creation of a tunnel over the facial nerve to enter the middle ear, and the endomeatal approach (EMA) is based on the completion of a groove in the posterior wall of external auditory canal. MATERIAL AND METHODS: A multicentre review of 208 patients with cochlear implants, comparing the different techniques. The complications were classified into major and minor. RESULTS: Among the 208 implanted patients, 10.5% (22 of 208) had complications. Of these, 2.88% (6 of 208) were major complications and 7.69% (16 of 208) were minor complications. Comparing the results obtained by the different approaches, the FR technique had the lowest rate of major complications (1.1%), followed by the EMA technique with 2.38% and SMA with 3.75%. As for minor complications, operations in the SMA group had the lowest rate (6.25%), followed by the EMA group (7.14%) and the group operated on using the FR technique presented the highest (10%). CONCLUSIONS: The 3 techniques described show very similar rates of complications. Consequently, we can conclude that they are safe and are alternatives.

Preliminary results in cochlear implant surgery without antromastoidectomy and with atraumatic electrode insertion: the endomeatal approach.

A surgical approach using the external auditory canal and the round window as a natural access pathway for cochlear implant positioning, the endomeatal approach, is described. This approach avoids performing an antromastoidectomy, the subsequent posterior tympanotomy and the promontorial cochleostomy. The endomeatal approach also allows an optimal insertion plane for electrode array atraumatic insertion through the round window.The technique was developed and practiced in 35 fresh temporal bones and then it was applied in ten patients. This surgery has an endomeatal first stage, which begins with a stapedectomy-like tympanomeatal flap. This flap allows an easy access to scala tympani via round window niche. The internal part of a groove is drilled on the posterior wall of the EAC. The groove is parallel to the EAC axis and starts in its inner border. Once the endomeatal stage is completed, a standard retroauricular approach is performed, in order to make the receptor-stimulator well and to complete the groove externally, until it connects the middle ear with the external mastoid surface. A flat second well is drilled in front of the first one to lodge the remaining electrode lead. In small children this well is deepened. The electrode array is introduced in the scala tympani through the RW and located into the groove. The electrode is covered and fixed inside the groove with bone paté. The extra length of the electrode lead is located in the second well and the receptor-stimulator is fixed in its well. The ground electrode is placed under the periosteum, the retroauricular incision is sutured, the tympanomeatal flap is restored and a dressing is placed into the EAC. Surgical time was significantly shorter than in standard approach. There were neither surgical nor healing complications. Electrode insertion was easy and complete and functional results were adequate. The goal of this approach is to avoid antromastoidectomy and posterior tympanotomy, which are replaced by the EAC groove. It is faster and safer, eliminating the risk of facial nerve injury. It also allows a better access to the round window, with a less traumatic electrode insertion, suitable for "soft surgery" performing. It may advantageously replace the classical transmastoideal approach.