Effect of audiological testing on programmable ventriculoperitoneal shunts

The hidden risks of hearing tests and programmable ventriculoperitoneal shunt valves

Programmable variable pressure valves were introduced in the 1980s, providing a non-invasive solution to post-operative alterations of the valve opening pressure to address problems of under or overdrainage. Since their increased use in the treatment of hydrocephalus, there have been case reports of unintentional alterations of the valve opening pressure following exposure to magnetic fields in everyday environments, from televisions to rollercoasters. Here we describe two cases of patients' programmable valves being altered following audiology assessments. We subsequently discuss some of the available research on the safety of these valves in various magnetic field strengths, alongside interim and updated recommendations made by the British Society of Audiologists with regards to testing of children with programmable shunts in place.

[Clinical protocol: audiological assessment of infants in Russian Federation. Part II]

This is the second part of the previously published clinical protocol of audiological assessment in infants. The goal of the protocol is unification approaches to audiological diagnosis of the infants. The following sections were included in the second part of the protocol: behavioral testing in infants, testing sequence, duration of the examination and necessity in follow-up, hearing assessment in special cases (premature children, children with congenital infections, after meningitis, with external ear abnormalities, single-sided deafness, with hydrocephalus and shunts, with auditory neuropathy spectrum disorder, with mild hearing loss and otitis media with effusion), medical report.

The Effects of Using Hearing Aids and Hearing Assistive Technologies on Programmable Ventriculoperitoneal Shunt

BACKGROUND

To investigate interaction between behind-the-ear (BTE) hearing aids, hearing assistive technologies, and programmable shunt valve to understand how use of BTE hearing aids in patients who underwent ventriculoperitoneal shunt (VPS) surgery affects the settings of a programmable shunt valve.

METHODS

In this study, we investigated the magnetic field (MF) generation of 3 BTE hearing aids made by different companies, 1 frequency modulated system using telecoil technology, and 1 wireless microphone technology and their interactions with 2 programmable shunt valves. All measurements were made in a silent booth using 2 different models. The influence of MF strength in the distance modeling was investigated based on the distance from source auditory prostheses. The measurements were recorded using a Gauss meter. In the anatomical modeling, the change in the settings and interaction of the valve in a bust mannequin were investigated.

RESULTS

No MF created by BTE hearing aids was detected in the distance modeling. The highest value measured was 32.67 μT (<90 dB noise) when BTE hearing aids and frequency modulated systems were used, and this value decreased as the distance increased. No MF generation was observed at measurements done for distances >10 mm. In the anatomical modeling, the settings of both programmable valves did not change under all acoustic conditions.

CONCLUSIONS

This is the first study to our knowledge examining the MF created by hearing aids and hearing assistive technologies and its impact on programmable valves and variations in their settings. Our findings showed that it is safe to use BTE hearing aids, frequency modulated systems, and wireless microphone technologies in patients with a programmable VPS.