Cochlear implants: Referral, selection and rehabilitation

Modified Veria Technique for Cochlear Implantation by Postaural Approach

There are various surgical techniques for cochlear implantation, classical one being mastoidectomy and posterior tympanotomy which has some disadvantages and complications like extensive bone work, violation of mastoid air cell system and fear of injury to vital structures like facial nerve. To minimize these problems, various modifications in cochlear implantation surgery has been done which includes introduction of Veria technique which also has certain disadvantages like extensive dissection and prolonged surgical time. In this article we are introducing an innovative technique of cochlear implantation where we have modified the pre-existing Veria technique that has been described in detail in the coming sections. Total 9 cases have been done so far with this modified Veria technique. This technique includes postaural approach with minimal soft tissue and bone work, making the cochlear implantation simple, easily doable, with less operating time, with minimal morbidity, faster healing due to smaller incision and avoiding facial nerve injury.

Ophthalmological screening of a paediatric cochlear implant population: a retrospective analysis and 12-year follow-up

AIMS

To determine the nature and prevalence of ophthalmological findings for a cohort of children in a paediatric cochlear implant program and to assist the clinician in devising an investigative plan for this population.

METHODS

Retrospective medical record review of children who underwent multichannel cochlear implantation at a tertiary care hospital between February 1996 and July 2008.

RESULTS

In all, 141 children (mean age 28 months, range 16 months to 9 years) had complete medical record documentation consisting of orthoptic and opthalmological examination, including cycloplegic refraction. A total of 59 children (41.8%) had ocular abnormalities with refractive errors being the most common abnormality. Hypermetropia was the most common refractive error and was found in 21 children (14.8%). Strabismus was found in six patients, with constant esotropia being the most common. Ocular pathology (excluding refractive or muscle abnormalities) were found in nine patients (6.3%). Three patients had syndromes associated with ocular findings including Waardenburg and Usher syndrome. During the follow-up period, 14 children were fitted with prescription lenses, 3 had strabismus surgery, and 2 underwent ptosis.

CONCLUSIONS

Routine orthoptic and ophthalmologic examination can be beneficial in the initial evaluation of children assessed for cochlear implants. Electroretinography is useful in evaluating children with unexplained congenital sensorineural hearing loss, suggestive symptoms including night blindness, unexplained reduction in visual acuity, or delayed motor milestones. Routine yearly follow-up may aid in the detection of changing refractive errors and the possibility of later-onset retinal degeneration.

Rehabilitation regimes based upon psychophysical studies of prosthetic vision

Human trials of prototype visual prostheses have successfully elicited visual percepts (phosphenes) in the visual field of implant recipients blinded through retinitis pigmentosa and age-related macular degeneration. Researchers are progressing rapidly towards a device that utilizes individual phosphenes as the elementary building blocks to compose a visual scene. This form of prosthetic vision is expected, in the near term, to have low resolution, large inter-phosphene gaps, distorted spatial distribution of phosphenes, restricted field of view, an eccentrically located phosphene field and limited number of expressible luminance levels. In order to fully realize the potential of these devices, there needs to be a training and rehabilitation program which aims to assist the prosthesis recipients to understand what they are seeing, and also to adapt their viewing habits to optimize the performance of the device. Based on the literature of psychophysical studies in simulated and real prosthetic vision, this paper proposes a comprehensive, theoretical training regime for a prosthesis recipient: visual search, visual acuity, reading, face/object recognition, hand-eye coordination and navigation. The aim of these tasks is to train the recipients to conduct visual scanning, eccentric viewing and reading, discerning low-contrast visual information, and coordinating bodily actions for visual-guided tasks under prosthetic vision. These skills have been identified as playing an important role in making prosthetic vision functional for the daily activities of their recipients.

Is psychological status a determinant of speech perception outcomes in highly selected good adolescent cochlear implant users?

OBJECTIVE

The main purpose of this study was to assess the relationship between the speech perception skills and state-trait anxiety in cochlear implant user adolescents who were highly selected good candidates. The impact of preoperative speech perception ability on postoperative speech perception and state-trait anxiety status were also examined.

SUBJECTS AND METHODS

The subjects for this study were 25 consecutively chosen congenitally profoundly deaf adolescents (12 boys, 13 girls) who received nucleus multi channel cochlear implants and were followed for at least a year at Hacettepe University. Daily Sentences in Turkish and State-Trait Anxiety Inventories (STAI) were administered to subjects after 12-72 months (mean: 35.28+/-18.27) of implant use.

RESULTS

The trait and state anxiety scores were matched with the relative rank of normal hearing subjects' trait-state anxiety scores and the analysis of post-implant state-trait anxiety findings shows that both state and trait anxiety scores were widespread but still in normal range. The correlation between trait, state anxiety scores and speech perception ability was not statistically significant in adolescent cochlear implant users. However, their preoperative speech perception scores were significantly correlated with their postoperative speech perception abilities.

CONCLUSION

The majority of adolescents, in this study, achieved varying degrees of open-set speech recognition and made greater gains than their previous auditory experience with hearing aids. Also, the indirect positive effects of early identification-amplification, communication therapy and counseling programs on their personal well-being is clearly observed from the outcomes of their state and trait anxiety scores. As a result of correlating the trait and state anxiety levels with pre- and post-implant speech perception skills, a significant negative correlation was expected. However, no statistical correlation was found between speech perception skills and the psychological outcomes. This result may be the indicator of the positive effect of the early habilitation-parental support and cochlear implant on the quality of life as the adolescents involved in this study were developmentally and audiologically ready for implantation. The present study provides understanding of the audiological and social-emotional influences of early identification and habilitation programs on adolescents with cochlear implants.