A Comparative Study of a Novel Adhesive Bone Conduction Device and Conventional Treatment Options for Conductive Hearing Loss

Abstract

Objective: To compare the audiological performance with the novel adhesive bone conduction hearing device (ADHEAR) to that with a passive bone conduction (BC) implant and to that with a bone conduction device (BCD) on a softband.

Study design: Prospective study in an acute setting, single-subject repeated measure in three situations: unaided, with conventional BCDs (passive implant or on softband), and with the ADHEAR.

Setting: Tertiary referral center.

Patients: Ten subjects with conductive hearing loss were evaluated with the ADHEAR. Five of these were users of a passive BC implant (Baha Attract with Baha4); five received a BCD (Baha4) on a softband for test purposes.

Intervention: Use of non-invasive adhesive bone conduction system for the treatment of conductive hearing loss.

Main outcome measures: Air and bone conduction thresholds, sound field thresholds, word recognition scores in quiet, and speech recognition thresholds in quiet and noise were assessed.

Results: Users of the passive BC implant received comparable hearing benefit with the ADHEAR. The mean aided thresholds in sound field measurements and speech understanding in quiet and noise were similar, when subjects were evaluated either with the ADHEAR or the passive BC implant. The audiological outcomes for the non-implanted group were also comparable between the ADHEAR and the BCD on softband.

Conclusions: Based on our initial data, the ADHEAR seems to be a suitable alternative for patients who need a hearing solution for conductive hearing loss but for medical reasons cannot or do not want to undergo surgery for a passive BC implant.

FIG. 1

The ADHEAR system. Connecting the audio processor to the adhesive adapter.

FIG. 2

Sound field audiometry. PTA4 thresholds in sound field were determined in the unaided condition, with the ADHEAR and with the bone conduction device. Box plots indicate the median (centred horizontal line) with 25%- and 75%-quartiles (upper and lower horizontal lines) and minimum and maximum values (whisker). The cross indicates the mean. Individual data are labeled according to subject identifier. The pBC Implant group is displayed on panel A, the BCD softband group on panel B. pBC indicates passive bone conduction; BCD, bone conduction device; PTA4, four frequency pure tone average across frequencies 0.5, 1, 2, and 4 kHz.

FIG. 3

Speech understanding in quiet. WRS was determined at 65 dB SPL using the Pruszewicz monosyllabic Polish word test in the pBC Implant group (A) and BCD softband group (B). SRT in quiet was measured with the same test in the pBC Implant group (C) and BCD soft band group (D). Box plots indicate the median (centred horizontal line) with 25%- and 75%-quartiles (upper and lower horizontal lines) and minimum and maximum values (whisker). The cross indicates the mean. Individual data are labeled according to subject identifier. pBC indicates passive bone conduction; BCD, bone conduction device; SRT, speech recognition threshold; WRS, word recognition score.

FIG. 4

Speech understanding in noise. The SRT in noise was determined using the Polish Sentence Matrix Test, with speech and noise coming from the front at a fixed noise level of 65 dB SPL and adaptive speech level in the pBC Implant group (A) and in the BCD softband group. Box plots indicate the median (centered horizontal line) with 25%- and 75%-quartiles (upper and lower horizontal lines) and minimum and maximum values (whisker). The cross indicates the mean. Individual data are labeled according to subject identifier. pBC indicates passive bone conduction; BCD, bone conduction device; SRT, speech recognition threshold; WRS, word recognition score.