Prognostic indicators in paediatric cochlear implant surgery: a systematic literature review

Abstract

Background

Paediatric cochlear implantation (PCI) requires complex case evaluation and counselling, surgical intervention, and habilitation. Outcomes vary and many cases have sub-optimal outcomes as a result of a broad spectrum of adverse influences.

Objective

To systematically review the literature to identify research papers that indicate a demonstrated outcome or prognostic factor in paediatric CI, the overall aim being to develop a prognostic index for clinical use.

Methods

Six main literature domains were assessed: medical/surgical; audiology; psychology; speech/language; education; and family. Search strategies were applied to appropriate databases and journals. A strict inclusion criterion was utilized. A critical appraisal tool was administered to evaluate the final eligible citations.

Results

The review identified 92 citations, of which 38 were eligible. Heterogeneity in study design prevented a quantitative meta-analysis of the data.

Discussion

While there are a large range of factors that impact PCI outcomes, well-constructed case control studies are limited in number and scope and relatively few demonstrated significant prognostic factors. Only four factors were identified as consistently influencing PCI outcomes: age at implantation, Connexin 26, inner ear malformations, and meningitis.

Conclusion

Evaluation of relevant adverse prognostic factors in paediatric CI remains a largely unreported field. Better identification of these factors is required for improving vital pre-operative counselling and resultant surgical expectations and outcomes.

Keywords:

• Paediatric cochlear implantation
• Prognostic factors
• Systematic review
• Hearing loss
• Case control studies

Acknowledgements

We would like to thank the clinical staff of the Hear and Say Centre for Deaf Children and Lia Lassig, Clinical Specialist Audiologist, Cochlear Implant Program, Royal Children's Hospital for their constructive advice and support during this research project.