Search Results (17)

Cartilage conduction hearing aids (CCHAs) are new devices that have attracted attention in recent years for external auditory canal atresia. In these devices, a vibrator is attached to the ear cartilage to transmit sound through vibration. In this study, we measure the mechanical impedance of the ear concha auriculae, which represents the mechanical load on the vibrator. To evaluate the output of the CCHAs, we develop a coupler simulating the ear cartilage that measures the sound pressure corresponding to the eardrum sound pressure of the normal ear. Consequently, the mechanical impedance of the developed coupler is several times larger than that of the human ear cartilage measured in this study; however, it is an acceptable value considering the difference in the contact area. The output sound pressure of the vibrator with the coupler simulating the ear cartilage roughly simulates the sound pressure in the ear canal with normal hearing (with the ear canal sealed). In this study, the measured mechanical impedance of the human ear cartilage is approximately 20 dB less than that of the mechanical coupler specified in IEC (International Electrotechnical Commission) 60318-6 for the evaluation of the bone conduction vibrator. Full article

Forty-nine children who started wearing cartilage conduction hearing aids (CC-HAs) before completing elementary school (17 with bilateral hearing loss and 32 with unilateral hearing loss) were followed-up and examined. The wearing and utilization status of the CC-HA and its progress to date were evaluated. In addition, 33 participants who purchased the CC-HAs were interviewed to assess the wearing effect. Eleven of seventeen children with bilateral hearing loss and 25 of 32 children with unilateral hearing loss continued to use the CC-HAs. In terms of wearing effect, a good wearing effect was reported, even by those with unilateral hearing loss. In cases where it was difficult to wear CC-HAs stably with pasting or ear tips, it was possible to fix them stably using commercially available hair bands and eyeglass vines. In two cases, the CC-HAs were worn from infancy. With ingenuity and appropriate educational and medical support, it is possible to wear CC-HAs from infancy. Full article

This systematic review evaluates the efficacy and benefit of cartilage conduction hearing aids (CC-HAs) and that factors that influence purchasing decisions. The hearing thresholds and functional gain following CC-HA wear were synthesised. A one-way analysis of variance compared the differences in the hearing thresholds and functional gain at individual frequencies and in patients with a variety of pathological changes. The synchronised aided hearing threshold and functional gain at 2.0 kHz were significantly better than at 0.5, 1.0, and 4.0 kHz. There was no significant difference in the synchronised unaided hearing thresholds across individual frequencies between 0.5 and 4.0 kHz. The synchronised functional gain in patients with atresia was significantly greater than in patients with aural atresia or stenosis and middle ear pathologies with normal ear canals. The acceptability of CC-HAs in terms of purchase decision is influenced by the condition of the external auditory meatus and severity of hearing loss, with the highest purchase rate seen in patients with aural atresia or stenosis. CC-HAs’ fitting procedure advantages and cosmetic considerations make these devices a viable and preferred choice for individuals with microtia and aural atresia. Additional research to evaluate the benefits towards emotional well-being is crucial to gain insights into the psychological impact of CC-HA use. Full article

Clinical findings on cartilage conduction hearing aids (CCHAs) have gradually become clear; however, few reports include a large number of cases. This study included 91 ears from 69 patients who underwent CCHA fitting in our hospital. Their ears were divided into six groups (i.e., bilateral aural atresia or severe canal stenosis, unilateral aural atresia or severe canal stenosis, chronic otitis media or chronic otitis externa with otorrhea, sensorineural hearing loss, mixed hearing loss, and conductive hearing loss) according to their clinical diagnosis and type of hearing loss. Most clinical diagnoses were aural atresia or meatal stenosis (bilateral, 21.8%; unilateral, 39.6%). The purchase rate of CCHAs was higher in the closed-ear group (bilateral, 77.3%; unilateral, 62.5%). In the bilateral closed-ear group, air conduction thresholds at 1000, 2000, and 4000 Hz and aided thresholds with CCHAs at 4000 Hz were significantly lower in the purchase group than the non-purchase group. No significant difference was observed between the purchase and non-purchase groups in the unilateral closed-ear group. In the bilateral closed-ear group, air conduction thresholds and aided thresholds were associated with the purchase rate of CCHAs. In the unilateral closed-ear group, factors other than hearing might have affected the purchase rate of CCHAs. Full article

Background and Objectives: Platelet-rich fibrin (PRF) membrane plays an important role in cell proliferation and aids in healing. This study aimed to assess the safety and efficacy of the addition of PRF to the graft in tympanoplasty. Materials and Methods: A retrospective study was conducted involving 47 patients with chronic dry eardrum perforation, who were candidates for different types of tympanoplasty (type I-IV). The study took place in the ENT department, County Emergency Clinical Hospital of Cluj-Napoca. In group 1 (27 patients) tympanoplasty was performed with a cartilage graft, while in group 2 (20 patients) a cartilage graft was used with the addition of a PRF membrane. The PRF clot was extracted and transformed into a thin membrane. Postoperative evaluation included otoendoscopy and otomicroscopy at 1, 3, 6, and 12 months after surgery, as well as pure-tone audiometry at 12 months. Results: Postoperative follow-up at 1, 3, 6, and 12 months showed a higher rate of graft survival in the PRF group than in the non-PRF group. At the 12-month mark, a successful outcome was observed in 95.0% of patients in the PRF group, while the success rate in group 1 was 70.4% (p < 0.05). The postoperative hearing threshold value was statistically significantly lower in the group with PRF, compared to the non-PRF group, being 18.4 ± 10.4 dB and 27.6 ± 16.2 dB (p < 0.001), respectively. Although the postoperative air-bone gap value did not differ significantly between groups, there was a greater improvement in the PRF group (p < 0.7). The PRF was well tolerated, and the incisions healed perfectly. Conclusions: The PRF membrane increases the rate of autograft survival and is therefore an effective material for patients with chronic perforations of the tympanic membrane. Full article

A relatively loud sound is audible when a vibrator is attached to the aural cartilage. This form of conduction is referred to as cartilage conduction (CC). In Japan, a new type of hearing aid has been developed using CC and has been available in clinical practice since 2017. A clinical study conducted prior to its launch demonstrated its benefits, particularly in patients with aural atresia who were unable to use air conduction hearing aids. Several studies have been published on the benefits of CC hearing aids since their introduction into clinical practice. Most of the patients included in these studies had canal stenosis or aural atresia, and the purchase rates of CC hearing aids in these patients were relatively high. However, the number of patients with canal-open ears was small, with overall poor results in the trials, with the exception of patients with continuous otorrhea. CC hearing aids are considered a good option for compensating for hearing loss in ears with canal stenosis or atresia in both bilateral and unilateral cases. However, CC hearing aids are not currently considered the first choice for patients with a canal-open ear. Full article

The cartilage-conduction hearing aid (CC-HA) is a new hearing device that is suitable for use in patients with conductive hearing loss. It has been 5 years since the introduction of the CC-HA. Although the number of users has increased, the CC-HA is not yet widely known. This study examines the effects of CC-HA on patients with conductive hearing loss and investigates factors that affect the willingness to use the device by comparing purchasers and non-purchasers of CC-HA in patients with unilateral conductive hearing loss. Eight patients had bilateral conductive hearing loss, and 35 had unilateral conductive hearing loss. Each patient underwent sound field tests and speech audiometry, and the effects of the CC-HA were compared with those of conventional bone conduction hearing aids (BC-HA). In patients with bilateral conductive hearing loss, the CC-HA was non-inferior to BC-HA. The CC-HA improved the hearing thresholds and speech recognition in patients with unilateral conductive hearing loss. Moreover, in patients with unilateral conductive hearing loss, experiencing the effect of wearing the CC-HA under conditions such as putting noise in the better ear could affect patients’ willingness to use the CC-HA. Full article

The ear molds and shells of hearing devices are generally designed using ear impressions. Computed tomography (CT) can provide information concerning ear structure, which can be utilized in computer-aided design to create hearing devices. This study aimed to compare the differences in hearing devices designed using either ear impressions or CT images. The ear chip of a cartilage conduction (CC) hearing device was designed based on the ear impression and CT images of patients with aural atresia. Three patients with bilateral (n = 1) or unilateral (n = 2) aural atresia participated in this study. The aided thresholds and subjective evaluations were compared. There were no serious problems with the use of either device, and no remarkable differences were observed regarding their respective audiological and subjective benefits. Regarding the subjective patient preferences, the hearing aid with the device designed via CT imaging was better in three ears of two patients, whereas the wearing comfort of the transducer was better for the device designed via the ear impression. The subjective evaluation of appearance varied among the cases. Finally, a device that was designed using CT findings was purchased for one patient. CT images can be utilized in computer-aided design to create CC hearing devices. Full article

Cartilage conduction hearing aids (CC-HAs) are a novel type of hearing aid relying on cartilage conduction, the so-called third auditory conduction pathway. However, CC-HAs have only recently entered routine clinical use, and therefore data on their usefulness are lacking. The purpose of this study was to examine the possibility of assessing whether individual patients would show good adaptation to CC-HAs. Thirty-three subjects (41 ears in total) underwent a free trial of CC-HAs. Age, disease category, and the pure-tone threshold of air and bone conduction, unaided field sound threshold, aided field sound threshold, and functional gain (FG) at 0.25, 0.5, 1, 2, and 4 kHz were compared between patients who subsequently purchased and did not purchase the CC-HAs. Overall, 65.9% of the subjects purchased CC-HAs after the trial. In comparison to non-purchasers, those who decided to purchase CC-HAs showed better pure tone hearing thresholds at high frequencies for both air conduction (2 and 4 kHz) and bone conduction (1, 2, and 4 kHz), as well as for aided thresholds in the sound field (1, 2, and 4 kHz) when using CC-HAs. Therefore, the high-frequency hearing thresholds of subjects trialing CC-HAs might be helpful for identifying those who are likely to benefit from them. Full article

Although hearing devices based on cartilage conduction have become more widely used in Japan, methods for evaluating the output volume of such devices have not yet been established. Although the output of air-conduction-based sound-generating devices (e.g., earphones and hearing aids) can be standardized via the head and torso simulator (HATS), this is not applicable to cartilage conduction devices because the simulated pinna is too soft (hardness: A5) compared with human aural cartilage. In this study, we developed polyurethane pinna that had the same shape but different degrees of hardness (A40, A20, and A10). We then compared the HATS results for the new pinna simulators with data from human ears. We found that the spectral shapes of the outputs increasingly approximated those of human ears as the simulated pinna hardness decreased. When a durometer was pressed against the ear tragus of a human ear, the hardness value ranged from A10 to A20. Accordingly, cartilage-conduction-based sound information could be obtained using a HATS that had a simulated pinna with a similar hardness value. Full article

Cartilage conduction hearing aids (CC-HA), bone anchored hearing aids (Baha), and ADHEAR are good choices to improve hearing in patients who cannot use air conduction hearing aids because of aural atresia or continuous otorrhea. As there are many overlaps in the characteristics of these devices, we conducted a comparative trial of CC-HA, Baha, and ADHEAR. We provided patients with the opportunity to select their devices. The data of 6 patients who underwent comparative trials in our department between October 2021 and August 2022 were retrospectively examined. The gains of Baha and CC-HA outweighed those of ADHEAR. Regarding the sound localization test, there was no significant tendency for any of the hearing devices. Regarding the Glasgow Benefit Inventory, there was no clear tendency among the three devices in the quality of life evaluation. The most satisfactory model was the one subjectively chosen by the patient, regardless of the gain and score of the sound source localization test. Therefore, we believe that it is necessary to provide an opportunity for comparative trials and a consultation with each patient in the process of selecting a device. Full article

Sound localization in daily life is one of the important functions of binaural hearing. Bilateral bone conduction devices (BCDs), middle ear implants, and cartilage conduction hearing aids have been often applied for patients with conductive hearing loss (CHL) or mixed hearing loss, for example, resulting from bilateral microtia and aural atresia. In this review, factors affecting the accuracy of sound localization with bilateral BCDs, middle ear implants, and cartilage conduction hearing aids were classified into four categories: (1) types of device, (2) experimental conditions, (3) participants, and (4) pathways from the stimulus sound to both cochleae. Recent studies within the past 10 years on sound localization and lateralization by BCDs, middle ear implants, and cartilage conduction hearing aids were discussed. Most studies showed benefits for sound localization or lateralization with bilateral devices. However, the judgment accuracy was generally lower than that for normal hearing, and the localization errors tended to be larger than for normal hearing. Moreover, it should be noted that the degree of accuracy in sound localization by bilateral BCDs varied considerably among patients. Further research on sound localization is necessary to analyze the complicated mechanism of bone conduction, including suprathreshold air conduction with bilateral devices. Full article

Hearing improvement represents one of the may valuable outcomes in microtia and aural atresia reconstruction surgery. Most patients with poor development in their hearing function have had a severe microtia. Conventional methods to improve hearing function are bone conduction and bone anchored hearing aids. Cartilage conduction hearing aids (CCHA) represents a new amplification method. This study assessed the outcomes and evaluated the impact and its safety in the patients with microtia and aural atresia whose hearing dysfunction did not improve after surgery for ear reconstruction in our hospital. Hearing functions were evaluated with pure tone audiometry or sound field testing by behavioral audiometry and speech audiometry before and after CCHA fitting. As a result, there was a significant difference between unaided and aided thresholds (p < 0.001). Speech recognition threshold and speech discrimination level also significantly improved with CCHA. The average functional gains of 14 ears were 26.9 ± 2.3 dB. Almost all parents of the patients reported satisfaction with the performance of CCHA, and daily communication in children with hearing loss also became better than usual. Full article

Because cartilage conduction—the transmission of sound via the aural cartilage—has different auditory pathways from well-known air and bone conduction, how the output volume in the external auditory canal is stimulated remains unknown. To develop a simulator approximating the conduction of sound in ear cartilage, the vibrations of the pinna and sound in the external auditory canal were measured using pinna simulators made of silicon rubbers of different hardness (A40, A20, A10, A5, A0) as measured by a durometer. The same procedure, as well as a current calibration method for air conduction devices, was applied to an existing pinna simulator, the Head and Torso Simulator (hardness A5). The levels for vibration acceleration and sound pressure from these pinna simulators show spectral peaks at dominant frequencies (below 1.5 kHz) for the conduction of sound in cartilage. These peaks were likely to move to lower frequencies as hardness decreases. On approaching the hardness of actual aural cartilage (A10 to A20), the simulated levels for vibration acceleration and sound pressure approximated the measurements of human ears. The adjustment of the hardness used in pinna simulators is an important factor in simulating accurately the conduction of sound in cartilage. Full article

Severe conductive hearing loss due to unilateral aural atresia leads to auditory and developmental disorders, such as difficulty in hearing in challenging situations. Bone conduction devices compensate for the disability but unfortunately have several disadvantages. The aim of this study was to evaluate the benefits of cartilage conduction (CC) hearing aids for speech perception in unilateral aural atresia. Eleven patients with unilateral aural atresia were included. Each participant used a CC hearing aid in the atretic ear. Speech recognition scores in the binaural hearing condition were obtained at low speech levels to evaluate the contribution of aided atretic ears to speech perception. Speech recognition scores were also obtained with and without presentation of noise. These assessments were compared between the unaided and aided atretic ear conditions. Speech recognition scores at low speech levels were significantly improved under the aided atretic ear condition (p < 0.05). A CC hearing aid in the unilateral atretic ear did not significantly improve the speech recognition score in a symmetrical noise presentation condition. The binaural hearing benefits of CC hearing aids in unilateral aural atresia were predominantly considered a diotic summation. Other benefits of binaural hearing remain to be investigated. Full article