Experimental comparison of different dressing materials forprevention of magnetic dislocation in cochlear implants

Introduction MRI in CI patients includes the risk of magnet dislocation. As a countermeasure, the application of a pressure bandage is recommended, which can provide varying degrees of protection against magnet dislocation depending on the material used and the examiner. The aim of this study was to compare the holding force of two established bandage materials in dependence of different examiners.

Material and methods: A dummy head was retroauricularly equipped with a force sensor (ME-Messsysteme GmbH, Germany) to measure the retention force of the wrapping bandage applied over it. A counter pressure element (CPE) similar to a cheque card transferred the force of the bandage to the measuring head with a contact area of 0,5cm².10 different examiners applied an elastic bandage and a indicator bandage to the test stand in 5 repetitions each.

Results With the elastic bandage in combination with the CPE, mean retention forces of 46.6 ± 17.3N were achieved (median:40.0N). In contrast, the indiactor bandage achieved an average force of 69.7 ± 12.3N (median:61.5N). This difference between both wrapping techniques was highly significant (p < 0.01). Overall, the results of the elastic wraps did not scatter more than those with the indicator bandage (Levene's test).

Summary It was known from preliminary studies that higher wrapping forces can be achieved with the indicator bandage. The indicator bandage is designed to ensure that different investigators achieve as equal a tension force as possible. We have not been able to prove this effect on the basis of our data. Nevertheless, the combination of an indicator wrap and a CPE is recommended for MRI in CI patients with implants that are not suitable for MRI because of the higher wrapping force.

Poster-PDF A-1497.pdf

Publication History

Article published online:
13 May 2021