Mick Metselaar

Self-reported disability and handicap after hearing-aid fitting and benefit of hearing aids: comparison of fitting procedures, degree of hearing loss, experience with hearing aids and uni- and bilateral fittings

Self-reported outcome on hearing disability and handicap as well as overall health-related quality of life were measured after hearing-aid fitting in a large-scale clinical population. Fitting was performed according to two different procedures in a double-blind study design. We used a comparative procedure based on optimizing speech intelligibility scores and a strictly implemented fitting formula. Hearing disability and handicap were assessed with the hearing handicap and disability inventory and benefit of hearing aids with the abbreviated profile of hearing aid benefit. Effects on health-related quality of life and depression were assessed with the EuroQol-5D questionnaire and the geriatric depression scale. We found that hearing-aid fitting according to either procedure had a significantly positive effect on disability and handicap associated with hearing loss. This effect lasted for several months. Only the effect on disability persisted after 1-year of follow-up. Self-reported benefit from hearing aids was comparable for both fitting procedures. Unaided hearing disability was more pronounced in groups of participants with greater hearing loss, while the benefit of hearing aids was independent from the degree of hearing impairment. First-time hearing aid users reported greater benefit from their hearing aids. The added value from a bilateral hearing-aid fitting was not significant. Overall health-related quality of life and incidence of depression did not alter after hearing-aid fitting.

Dutch Cochlear Implant Group (CI-ON) Consensus Protocol on Postmeningitis Hearing Evaluation and Treatment

Objective: One of the most devastating sequelae of bacterial meningitis is profound hearing loss or even deafness. Although cochlear implantation is able to restore (some) hearing abilities, obliteration due to fibrosis and especially calcification of the cochlea in the postmeningitis period is limiting the success rate of an implantation. A national consensus assembled in a postmeningitis follow-up protocol has to increase awareness and thus the chances of an early detection and possible intervention when profound hearing loss occurs. Setting: All cochlear implant (CI) centers of The Netherlands located in the 8 academic otorhinolaryngology and audiology departments of The Netherlands, gathered in the Dutch Cochlear Implant Group (CI-ON, Cochlear Implant Overleg Nederland). Intervention: A protocol proposed by 3 centers was sent to all other CI centers in The Netherlands to review and agree on. Main Outcome Measures: The CI centers agreed on the need for, and use of, the proposed protocol. Keystones of the protocol are treatment with dexamethasone before start of antibiotics, early magnetic resonance imaging and repeated audiological follow-up, and urgent referral to a CI center in all cases with greater than 30 dB SNHL. Conclusion: The Cochlear Implant Centers in The Netherlands (CI-ON) have agreed on a protocolized follow-up after bacterial meningitis to increase the chances of an early detection and possible intervention should profound hearing loss occur.

Long-term changes in cerebellar activation during functional recovery from transient peripheral motor paralysis.

Localized altered cerebellar cortical activity can be associated with short-term changes in motor learning that take place in the course of hours, but it is unknown whether it can be correlated to long-term recovery from transient peripheral motor diseases, and if so, whether it occurs concomitantly in related brain regions. Here we show in a longitudinal fMRI study of patients with unilateral Bells palsy that increases in ipsilateral cerebellar activity follow the recovery course of facial motor functions over at least one and a half years. These findings hold true for changes in brain activity related to both oral and peri-orbital activation, even though these processes are differentially mediated by unilateral and bilateral brain connectivities, respectively. Activation of non-facial musculature, which was studied for control, does not show any change in cerebellar activity over time. The localized changes in cerebellar activities following activation of facial functions occur concomitantly with increases in activity of the facial region in the contralateral primary motor cortex suggesting that the cerebellum acts together with the cerebral cortex in long-term adaptation to transient pathological sensorimotor processing.

Comparison of speech intelligibility in quiet and in noise after hearing aid fitting according to a purely prescriptive and a comparative fitting procedure

We compared two different types of hearing-aid fitting procedures in a double-blind randomized clinical study. Hearing aid fittings based on a purely prescriptive procedure (the NAL-RP formula) were compared to a comparative fitting procedure based on optimizing speech intelligibility scores. Main outcome measures were improvement of speech intelligibility scores in quiet and in noise. Data were related to the real-ear insertion responses that were measured after fitting. For analysis purposes subgroups were composed according to degree of hearing loss, characterized by unaided speech intelligibility in quiet, previous experience with hearing aids, unilateral or bilateral fittings and type of hearing aid. We found equal improvement of speech intelligibility in quiet, while fitting according to the prescriptive formula resulted in a somewhat better performance as expressed by the speech-to-noise ratio in comparison to the comparative procedure. Both procedures resulted in comparable real-ear insertion responses.

Osteoradionecrosis of tympanic bone: Reconstruction of outer ear canal with pedicled skin flap, combined with hyperbaric oxygen therapy, in five patients

OBJECTIVE To evaluate the results of one-stage surgical repair of the meatal skin defect in patients with long-lasting osteoradionecrosis of the outer ear canal, using a postauricular, inferiorly pedicled skin flap. All patients were also treated with hyperbaric oxygen both pre- and post-operatively. METHODS A prospective study evaluating the results of a one-stage surgical procedure to repair the meatal skin defect in five patients with osteoradionecrosis of the outer ear canal. All patients were treated with hyperbaric oxygen both pre- and post-operatively. RESULTS In four of the five patients, intact canal skin was achieved after surgery and hyperbaric oxygen therapy. One patient needed a second operation to cover a small remaining area of bare bone. In one patient, wound healing was unsatisfactory and an area of bare bone remained. CONCLUSION In cases of osteoradionecrosis of the outer ear canal, the skin defect can be repaired with an inferiorly pedicled skin flap. Although not yet scientifically proven, the peri-operative application of hyperbaric oxygen may be of additional value to improve wound healing in areas of compromised tissue.

Comparative studies on hearing aid selection and fitting procedures: a review of the literature

Although a large number of fitting procedures have been developed and are nowadays generally applied in modern hearing aid fitting technology, little is known about their effectiveness in comparison with each other. This paper argues the need for comparative validation studies on hearing aid fitting procedures based on the design of a randomized clinical trial and carried out in a large-scale clinical population. These studies are hard to conduct but can provide detailed information on the various aspects of the rehabilitation with hearing aids. The design of several recently reported comparative studies of hearing aid fitting procedures will be reviewed. This gives rise to a number of comments on aspects like, study design, composition of the study population and definition of outcome measures rather than on the outcome or conclusions of these studies themselves.

Long-term effect of prednisolone on functional blink recovery after transient peripheral facial motor paralysis.

Objective. To determine the functional recovery in patients with severe transient peripheral facial motor paralysis (Bell palsy). Study Design. Prospective controlled trial. Setting. Academic medical center. Subjects and Methods. Blink recovery was studied in 2 groups of severely affected Bell palsy patients during a follow-up period of 84 weeks. The patients in one group received prednisolone within the first week after the onset of symptoms. No medication was given to the other group. A control group of healthy subjects was also included. Simultaneous orbicularis oculi muscle activity and eyelid kinematics were recorded by surface electromyographic (EMG) recording and eyelid search coils, respectively. Results. At the beginning of the paralysis, very little integrated orbicularis oculi muscle activity and eyelid movement was measured at the palsied side of the face. Thirteen weeks later, the integrated orbicularis oculi EMG and functional blink recovery gradually improved until 39 weeks. Beyond, only the integrated orbicularis oculi EMG slightly increased. At 84 weeks, the integrated orbicularis oculi EMG was significantly larger in the prednisolone group compared with the control group. The integrated EMG of the nonmedicated group recovered to normal values. Curiously enough, the functional blink recovery at the palsied side remained reduced to 64% compared with the healthy controls in the prednisolone-treated group and to 36% in the nonmedicated group. Conclusion. The authors demonstrate that prednisolone significantly increased the orbicularis oculi muscle activity and significantly improved functional blink recovery in severely affected Bell palsy patients. However, the increase of muscle activity was insufficient to restore functional blinking to normal values.

Decline of Low-Frequency Hearing in People With Ski-Slope Hearing Loss; Implications for Electrode Array Insertion

HYPOTHESIS The decline of low-frequency hearing in people with ski-slope hearing loss varies and might depend on etiology. BACKGROUND People with ski-sloping hearing loss might benefit from cochlear implantation with preservation of residual hearing. To reduce the risk of losing low-frequency hearing after implantation, the electrode-array can be inserted partially up to the desired frequency. That, however, obstructs electrical stimulation of lower frequencies. To decide between complete or partial insertion, knowledge regarding the natural decline of low-frequency hearing is helpful. METHODS Patients with at least two ski-slope audiograms over time were selected. We calculated progression at lower frequencies for 320 patients. Etiologies for hearing loss were retrieved from medical records. Progression of hearing loss was analyzed separately for patients with uni- and bilateral hearing losses. Relative progression of hearing loss was obtained by comparing progression to a reference group. RESULTS Average progression of PTA was 1.73 dB/yr and was not significantly different in the bilateral and unilateral group. Etiologies that did not show significantly more progression compared with the reference group could be identified as single or short-lasting pathologic events, whereas long-lasting conditions had significant more progression of PTA. CONCLUSION Patients with a ski-slope hearing loss that was caused by a single or short-lasting event have low progression rate and are viable for partial insertion to minimize the risk of damaging residual low-frequency hearing. In the absence of such an event, complete insertion should be considered because faster than normal deterioration of low-frequency hearing over time will probably limit the advantage of preservation of residual hearing.

Evaluation of magnetic resonance imaging diagnostic approaches for vestibular schwannoma based on hearing threshold differences between ears: Added value of auditory brainstem responses

Objective: This study investigates the most appropriate audiometric criterion in deciding which patients with asymmetric hearing loss should be referred to MRI to exclude a lesion in the cerebellopontine angle (CPA). Careful selection of patients could improve resource utilization while preventing unnecessary investigations with accompanying burden and costs. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: Of all the patients who were referred to our clinic between 1997 and 2012, the records were reviewed of those who underwent pure-tone audiometry, auditory brainstem response (ABR) testing, and had a Gadolinium-enhanced MRI of the CPA. Intervention: Regarding interaural pure-tone threshold differences at single or multiple (averaged) frequencies, we assigned multiple possible cut-off values (dB) defining an aberrant result, suggestive for CPA lesions. Results were compared with MRI to calculate sensitivity and specificity for every cut-off value. These were visualized as ROC curves enabling qualitative comparison. Added value of ABR was assessed as well. Main Outcome Measures: Sensitivity and specificity of various criteria to decide which patients with asymmetric hearing loss to send to MRI to exclude a CPA lesion. Results: In total, 1016 records were reviewed. Two hundred ninety-four subjects (29%) were diagnosed with a CPA lesion on MRI. Sensitivity and specificity for audiometry results differed greatly depending on the predefined cut-off value for hearing threshold difference (40–95% sensitivity and 20–90% specificity). Best ROC curves were obtained when threshold differences at two or three higher frequencies were averaged. Adding results of ABR to the threshold criterion yielded a slightly better ROC curve, although sensitivity decreased. Conclusions: The best criterion to decide which patient with asymmetric hearing loss should be referred to MRI is based on the average bone conduction threshold difference at multiple (two or three) higher frequencies. The extent of the average threshold difference between ears that is used as a cutoff will mainly depend on treatment modality and (eventually) on resource costs and on the burden of Gadolinium-enhanced magnetic resonance imaging. Results of ABR can have little added value when only patients with a unilateral abnormal ABR at the worse hearing ear are referred to MRI. However, a lower sensitivity must then be accepted.