Janny R. Hof

Otoacoustic emissions at compensated middle ear pressure in children

Middle ear pathology has a negative effect on the detectability of otoacoustic emissions. In this study, we investigated the effect of compensating a deviant static middle ear pressure while measuring transient evoked otoacoustic emissions (TEOAEs). In 59 children (mean age 4 years, 5 months) TEOAEs were measured twice in one session: first at ambient pressure and than at compensated middle ear pressure. On average, TEOAE amplitudes increased by 1.9 dB as a result of middle ear pressure compensation. The amplitude increase was largest in frequency bands centred at 1 and 2 kHz and a statistically significant correlation was found between the amount of compensated pressure and the TEOAE amplitude increase. In the higher frequency bands centred at 3 and 4 kHz, TEOAE amplitudes were almost insensitive to pressure compensation. These results show that measuring OAEs at compensated middle ear pressure enhances the amplitude of TEOAEs, and thus improves the detectability.

Auditory maturation in premature infants: a potential pitfall for early cochlear implantation.

To describe spontaneous hearing improvement in the first years of life of a number of preterm neonates relative to cochlear implant candidacy.

Minimally Invasive Ponto Surgery compared to the linear incision technique without soft tissue reduction for bone conduction hearing implants: study protocol for a randomized controlled trial.

BackgroundOver the last years, less invasive surgical techniques with soft tissue preservation for bone conduction hearing implants (BCHI) have been introduced such as the linear incision technique combined with a punch. Results using this technique seem favorable in terms of rate of peri-abutment dermatitis (PAD), esthetics, and preservation of skin sensibility. Recently, a new standardized surgical technique for BCHI placement, the Minimally Invasive Ponto Surgery (MIPS) technique has been developed by Oticon Medical AB (Askim, Sweden). This technique aims to standardize surgery by using a novel surgical instrumentation kit and minimize soft tissue trauma.MethodsA multicenter randomized controlled trial is designed to compare the MIPS technique to the linear incision technique with soft tissue preservation. The primary investigation center is Maastricht University Medical Center. Sixty-two participants will be included with a 2-year follow-up period. Parameters are introduced to quantify factors such as loss of skin sensibility, dehiscence of the skin next to the abutment, skin overgrowth, and cosmetic results. A new type of sampling method is incorporated to aid in the estimation of complications. To gain further understanding of PAD, swabs and skin biopsies are collected during follow-up visits for evaluation of the bacterial profile and inflammatory cytokine expression.The primary objective of the study is to compare the incidence of PAD during the first 3 months after BCHI placement. Secondary objectives include the assessment of parameters related to surgery, wound healing, pain, loss of sensibility of the skin around the implant, implant extrusion rate, implant stability measurements, dehiscence of the skin next to the abutment, and esthetic appeal. Tertiary objectives include assessment of other factors related to PAD and a health economic evaluation.DiscussionThis is the first trial to compare the recently developed MIPS technique to the linear incision technique with soft tissue preservation for BCHI surgery. Newly introduced parameters and sampling method will aid in the prediction of results and complications after BCHI placement.Trial registrationRegistered at the CCMO register in the Netherlands on 24 November 2014: NL50072.068.14. Retrospectively registered on 21 April 2015 at ClinicalTrials.gov: NCT02438618. This trial is sponsored by Oticon Medical AB.

Short-term results from seventy-six patients receiving a bone-anchored hearing implant installed with a novel minimally invasive surgery technique

Short-term results from seventy-six patients receiving a bone-anchored hearing implant installed with a novel minimally invasive surgery technique

Percutaneous bone-anchored hearing system implant survival after 550 primary implant surgeries

The Bone-Anchored Hearing System (BAHS) has become an established option for rehabilitation of several type of hearing impairment such as conductive hearing loss, mixed hearing loss and single-sided deafness. Overall good outcomes have been reported. Nevertheless, complications such as inflammation of the skin around the percutaneous abutment, pain and implant loss are related to BAHS. For implant loss stability, primary and secondary stability are important concepts. Primary stability is defined as implant stability immediately after surgery. Dental studies show that primary stability is influenced by implant design, surgical technique, bone quantity and bone quality. Secondary stability is defined as stability over time and is determined by primary stability and osseointegration. In dental implants, osseointegration is influenced by surgical trauma, implant design, smoking status and other subject-related factors such as diabetes and hygiene. In BAHS, implant loss rates of 8.3%-18% have been reported. 3-mm implants, young age, age of 60 or higher and male status have been described as risk factors for implant loss. In this study, we aimed to analyse implant survival rates for BAHS surgery including risk factors for the population in Maastricht University Medical Centre+ (MUMC), the Netherlands.

Compensating for deviant middle ear pressure in otoacoustic emission measurements, data, and comparison to a middle ear model.

Objective Deviant middle ear pressure has a negative effect on the forward and backward transmission of stimulus and emissions through the middle ear. Resolving this deviant middle ear pressure is expected to lead to better middle ear transmission and, as a result of this, stronger otoacoustic emissions, which are better detectable. We investigated the effect of compensation o a deviant tympanic peak pressure on click-evoked otoacoustic emissions (CEOAEs). Second, we compared patient data to model predictions made by Zwislocki’s middle ear model. Setting University Medical Center. Patients Fifty-nine children aged between 0.5 and 9 years (mean, 4.4 yr). Intervention Hearing investigations including CEOAE measurements at ambient and at compensated tympanic peak pressure (TPP). Main Outcome Measure CEOAEs at ambient and compensated TPP. Results Compensation of TPP resulted in higher emission amplitudes below 2 kHz (increase of 8–11 dB). In addition, the compensated measurement showed an increased phase lag (up to one-fourth cycle). For ears with mild deviations of TPP, Zwislocki’s model could describe these changes. Pressure compensation was well described by a compliance increase of the tympanic membrane, the malleus, and the incus. Conclusion Compensating the ear canal pressure for negative tympanic peak pressure increased CEOAE amplitudes below 2 kHz and increased the phase lag. These changes can be predicted from an increase of the compliance of the tympanic membrane, incus, and malleus, as a consequence of the pressure compensation.

Otoacoustic emissions at compensated middle ear pressure: preliminary results

Abstract Otoacoustic emissions (OAEs) are widely accepted for neonatal screening of congenital and early acquired sensori-neural hearing loss. The presence of middle ear pathology has a negative effect on the presence of OAE. In this study we investigated whether measuring OAEs at compensated middle ear pressure (CMEP) resulted in a higher pass rate than at ambient pressure. The results showed a higher pass rate of OAEs at CMEP than at ambient pressure, but in individual cases measurement at CMEP can result in a fail while there was a pass at ambient pressure.