Evaluating the success of a newly introduced Feed and Wrap protocol in magnetic resonance imaging scanning of the temporal bone for the evaluation of congenital sensorineural hearing loss.

OBJECTIVES

Magnetic resonance imaging (MRI) of the temporal bones, specifically of the cochlea and retro-cochlear pathway, is an important investigation in the diagnostic workup and management of congenital hearing loss. However, obtaining a diagnostic quality MRI scan depends upon the need for the infant to remain still for the duration of the scan. The Feed and Wrap (F + W) technique is a method that has been used successfully in infants for scans of other parts of the body, but has not been properly studied in MRI scans performed for hearing loss. The primary aim was to evaluate the diagnostic success rate of a newly introduced Feed and Wrap MRI scanning protocol used for assessment of sensorineural hearing loss in infants at Western Australia's Tertiary Paediatric hospital over the last three years. The secondary aims were to discuss the advantages and disadvantages of this technique and to review the available published literature on this technique and compare it to our case series.

METHODS

All F + W MRI scans performed for the investigation of congenital hearing loss between 2016 and 2019 at the King Edward Memorial Hospital for Women and Perth Children's Hospital were retrospectively reviewed. The primary outcome was the diagnostic utility of the MRI scan with a diagnostic scan defined as the ability to diagnose or exclude radiological causes of sensorineural hearing loss.

RESULTS

53 MRI scans of the temporal bone and brain were identified. 86.8% of scans were diagnostic. The mean age of infants who underwent diagnostic scans was 6.8 weeks old compared to 10.9 weeks (p = 0.01) for those who had non-diagnostic scans. The optimal age cut off for F + W technique was ≤10 weeks. The odds of failure are 16.7 (95%CI 6.5-42.8, p = 0.003) times higher above the cut of age of 10 weeks compared to ≤10 weeks.

CONCLUSION

The F + W technique is a viable method for obtaining diagnostic quality MRI scans of the inner ear structures in infants with hearing loss, with a greater likelihood of success when applied in younger infants.