Application of "banana cochleostomy" and looped electrode insertion for cochlear implantation in children with common cavity malformation and cystic forms of cochlear hypoplasia

Outcome of cochlear implantation in a case of cochlear aplasia with cochlear nerve deficiency

Cochlear nerve deficiency in cochlear aplasia is a contraindication for cochlear implantation (CI) anticipating poor auditory response. Few authors have reported auditory outcomes even without nerves following CI. This study outlines the audiological outcomes of a patient in early childhood with cochlear aplasia and cochlear nerve deficiency who underwent CI. Auditory and speech-language development were assessed using the Categories of Auditory Performance (CAP) scale, Speech Intelligibility Rating (SIR) scale and Ling-6 sound test; at the time of switch-on, after 6 and 12 months of auditory verbal therapy. Significant differences across CAP, SIR and Ling-6 sound detection scores were noted, with the highest mean scores at the 12th-month postimplantation, indicating substantial improvement in auditory and speech-language skills. In cochlear aplasia cases, residual cochlear elements and nerve fibres cannot be ruled out. Our report emphasises the need for research, as this has the potential to impact the existing guidelines for CI candidacy.

Pre- and post-operative imaging of cochlear implants: a pictorial review

Cochlear implants are increasingly used to treat sensorineural hearing disorders in both children and adults. Pre-operative computed tomography and magnetic resonance imaging play a pivotal role in patient selection, to rule out findings that preclude surgery or identify conditions which may have an impact on the surgical procedure. The post-operative position of the electrode array within the cochlea can be reliably identified using cone-beam computed tomography. Recognition of scalar dislocation, cochlear dislocation, electrode fold, and malposition of the electrode array may have important consequences for the patient such as revision surgery or adapted fitting.

Cochlear implantation in children with inner ear malformation: A multicenter study on auditory performance and speech production outcomes

OBJECTIVES

This multicenter study evaluated the auditory performance and speech production outcomes of cochlear implantation in children with inner ear anomaly and compared the outcomes of patients with different kinds of malformation.

METHODS

Cochlear implantation was performed in 107 children with inner ear malformation at four tertiary academic centers. The categories of auditory performance (CAP) and speech intelligibility rating (SIR) scores were evaluated preoperatively and one year and two years postoperatively.

RESULTS

Types of inner ear malformation and their frequencies were: incomplete partition type-I, 19 (17.8%) patients; incomplete partition type-II, 31 (29%), common cavity, 17 (15.9%), cochlear hypoplasia, 17 (15.9%), and isolated enlarged vestibular aqueduct (isolated EVA), 23 (21.5%) patients. EVA was the coexisting anomaly in 27(25.2%) subjects. The median CAP and SIR scores improved significantly during the first two years after cochlear implantation in all groups (p-values <0.001 and < 0.001, respectively). No significant difference was seen in CAP and SIR scores of children with different inner ear malformations (p-value = 0.147 and 0.570, respectively) or in patients with isolated EVA compared to coexisting EVA (p-value = 0.538 and 0.075, respectively).

CONCLUSION

The median CAP and SIR scores two years after surgery were 5 (Understanding of common phrases without lip-reading) IQR: 4-6, and 3 (Connected speech is intelligible to a listener who concentrates and lip-reads within a known context) IQR: 3-4, respectively. Auditory performance and speech production were significantly improved in all inner ear malformation patient groups, and no significant difference was observed between the scores of patients with different types of anomaly.

Rounded Insertion Technique for Cochlear Implantation Surgery to Treat Cystic Inner Ear Malformation

OBJECTIVE

This article outlines the advantages and applicability of the rounded insertion technique of cochlear implants in patients with cystic inner ear malformation. This technique enables the insertion of the maximum number of electrodes and prevents the unwanted entry of electrodes into the internal auditory canal.

METHODS

We conducted a retrospective chart review of consecutive patients with cochlear hypoplasia (CH) and/or common cavity (CC) who underwent CI (cochlear implantation) via rounded insertion technique. The position of the electrode array in each patient was confirmed postoperatively via X-ray, and the number of functional electrodes was confirmed during the mapping process.

RESULTS

This study included five male and two female patients (median age: 3 years; age range: 2-7 years). Among the seven patients, four received a cochlear implant on the right side, one on the left side, and two bilaterally. Of the nine ears, six were cases of CH, and three were CC. All cochlear implant surgeries via rounded insertion technique were completed without complications. The maximum number of electrode contacts with fair function in the cystic cochlea was confirmed via postoperative X-ray and the subsequent mapping process.

CONCLUSION

This consecutive series of patients demonstrated the safety and reliability of rounded insertion technique for CI in patients with CH and/or CC.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2229-2233, 2020.