When Hearing Aids Go Bad: An FM Success Story · Hearing Aid Program has a significant impact on the hearing aid industry.In fiscal year 2004, over 312,000 hearing aids were dispensed

J Am Acad Audiol 16:809–821 (2005)

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*Bay Pines VA Healthcare System, Bay Pines, Florida; †University of South Florida

Rachel McArdle, Ph.D., Bay Pines VA Healthcare System, Audiology (126), P.O. Box 5005, Bay Pines, FL 33744; Phone:727-398-9395; Fax: 727-319-1209; E-mail: [email protected]

Portions of this work were supported by Phonak, Inc. and by Rehabilitation Research and Development Service,Department of Veterans Affairs through a Merit Review.

When Hearing Aids Go Bad: An FM Success Story

Rachel McArdle*†

Harvey B. Abrams*†

Theresa Hnath Chisolm†*

Abstract

Both clinical and research findings support the effectiveness of frequency-modulated (FM) technology among individuals who continue to encountersignificant communication problems despite the use of conventional hearinginstruments. The use rate of FM devices throughout the nation, however,remains disappointingly low.The authors present a case of a longtime hearingaid user whose hearing aids provided decreasing benefit as his hearingimpairment increased to the extent that cochlear implantation was considered.Through the establishment of patient-specific treatment goals, the provisionof appropriate FM technology as verified through real-ear measurements,and careful and deliberate counseling and follow-up, this patient was able torealize significant communication benefits as reported through several self-assessment measures.The cost-benefit implications of FM technology versuscochlear implantation are discussed.

Key Words: Bilateral, hearing aids, hearing loss, rehabilitation of hearingimpaired

Abbreviations: BTE = behind the ear; CI = cochlear implant; COSI = Client-Oriented Scale of Improvement; CPHI = Communication Profile for the HearingImpaired; FM = frequency modulated; NAL-R = National Acoustic Laboratories—Revised; REIG = real-ear insertion gain; RMS = root mean square; SG =some guy;VA = Veterans Affairs;VAMC = Veterans Affairs Medical Center;WTP= willingness to pay

Sumario

Tanto los hallazgos clínicos como de investigación apoyan la eficiencia de latecnología de frecuencia modulada (FM) entre aquellos individuos que con-tinúan presentando problemas significativos de comunicación a pesar del usode instrumentos auditivos convencionales. La tasa de uso de los dispositivosde FM en el país, sin embargo, continúa siendo frustrantemente baja. Losautores presentan el caso de un usuario de audífonos de larga evolución, paraquién su auxiliar auditivo aportaba un beneficio en disminución conforme suhipoacusia aumentaba, al punto que se consideró colocarle un implante coclear.Luego de establecer metas de tratamiento específicas para el paciente, conel uso de una tecnología FM apropiada, verificada a través de mediciones deoído real, y con una consejería y un seguimiento cuidadosos, este pacientepudo obtener beneficios significativos en la comunicación, pudiéndose demostrarusando varias medidas de auto-evaluación. Se discuten las implicaciones decosto/beneficio de la tecnología FM versus la implantación coclear.

Palabras Clave: Bilateral, auxiliares auditivos, hipoacusia, rehabilitación delhipoacúsico

Journal of the American Academy of Audiology/Volume 16, Number 10, 2005

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The Veterans Affairs (VA) NationalHearing Aid Program has a significantimpact on the hearing aid industry. In

fiscal year 2004, over 312,000 hearing aidswere dispensed to eligible veterans (anaverage rate of 1,240 instruments eachbusiness day) at a cost of over $118,000,000.The hearing aids issued by the VA in calendaryear 2003 represented 54.4% of the entirehearing aid industry’s market growth (Strom,2004).The VA now accounts for more than onein seven (14.4%) of all hearing aids dispensedin the United States (Strom, 2004).

Of the close to 200,000 veterans whoreceived hearing aids this year, an estimated25% have a severe-to-profound hearingimpairment (Dennis, pers. comm., 2004).Individuals with severe-to-profound hearingimpairment present a significant challengefor audiologists since the severity of theirhearing impairment imposes a greater impacton their communication abilities thantypically can be resolved by conventionalamplification alone. Consequently, tomaximize their limited communicationabilities, many of these patients requiremultiple visits, placing a further strain on asystem attempting to manage ever-increasingworkload demands.

Among treatment options available toveterans with severe-to-profound hearingimpairment is cochlear implantation.Presently there are ten VA Cochlear Implant(CI) Centers that have historically beenestablished through a review and approvalmechanism that takes into account facilities,staffing, training, and experience. Selected VAMedical Centers have been performingcochlear implantations for over ten years.Patients seen at non-CI VA Medical Centerswho are candidates for implantation arereferred to a VA CI Center in their generalgeographical region for evaluation andimplantation if they meet the audiological andsurgical criteria set forth by the Food andDrug Administration. Once implanted,patients are required to return to the VA CICenter for subsequent programming andfollow-up. This process usually requires six

return visits in the first year followingimplantation. In the event that the devicerequires service, the CI patient returns tothe VA CI Center as VA audiology clinics innon-CI VA Medical Centers generally do nothave clinicians with the knowledge, skills, orequipment to repair or modify the processor.

While clinical experience indicates theoutcomes associated with cochlear implantprocedures performed in the VA are verygood, the need to travel to a CI Center, oftenfar from home, for multiple visits may belimiting the number of potential CI recipientsin the veteran population who elect toundergo the preliminary evaluation. Inaddition, there are patients who are ineligiblefor implantation due to comorbid conditions,and/or otologic and audiologiccontraindications, as well as those who declinedue to spousal responsibilities, and/orobjections to or fear of the surgery. Indeed, itis estimated that only 50 veterans wereimplanted at VA CI Centers in the past year(Dennis, pers. comm., 2004).1 If 25% of the200,000 veterans receiving hearing aids thisyear have severe-to-profound hearing loss,and are thus cochlear implant candidates,then one can only conclude that thepercentage of eligible veterans receivingcochlear implants is relatively small.

The relatively low implantation ratesuggests a need to evaluate other treatmentoptions for veterans with severe-to-profoundhearing impairment, who continue to reportsignificant communication problems despiteregular use of amplification. One promisingtreatment option is the use of FM (frequency-modulated) technology. Despite researchfindings that have demonstrated the clinicalefficacy of FM technology (Jerger et al, 1996;Sanford and Kierkhaefer, 2002; Boothroyd,2004), our clinical experience andmanufacturer report (Ermann, pers. comm.,2003) indicate a low use rate of FM systemsin the adult population. Researchers havesuggested several reasons for this low use rateincluding a lack of convenience (e.g., a needto recharge batteries daily), cosmetics (e.g.,increased attention to hearing loss due to

Abreviaturas: BTE = retroauricular; CI = implante coclear; COSI = Escala deMejoría Orientada al Cliente; CPHI = Perfil de Comunicación del Hipoacúsico;FM = frecuencia modulada; NAL-R = Laboratorio Nacional de Acústica –Revisado; REIG = ganancia de inserción en oído real; RMS = raíz mediacuadrada; SG = alguna persona; VA = Asuntos de Veteranos; VAMC = CentroMédico de Asuntos de Veteranos; WTP = deseo de pagar

When Hearing Aids Go Bad/McArdle et al

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the need to “point” a transmitter at thespeaker), a need for considerable instructionin device use, and/or device cost (e.g., Jergeret al, 1996; Boothroyd, 2004; Valente, pers.comm., 2005). While high cost may be adeterrent to FM use in the private sector,within the VA healthcare system, FM devices(receivers and transmitters) are provided toeligible veterans at no cost to the patientthrough the VA national hearing aid contract.During fiscal year 2004, approximately 1100FM systems were issued to veteransnationwide (Noe, pers. comm., 2004), aseemingly low figure considering theincidence of significant hearing loss in theveteran population.

Recently, the authors undertook a studyat two VA audiology clinics (Bay Pines VAMC[Veterans Affairs Medical Center] andMountain Home VAMC) to examine outcomesof FM use in veterans with significant hearingloss who are provided with considerablecounseling, coaching, and instructions duringa trial period of device use (Chisolm et al,2004; Noe et al, 2004). During counselingsessions, issues related to convenience andcosmetics as well as repeated instructionson device use were addressed. Several of theparticipants in this study met the audiologicalcriteria to be considered candidates for acochlear implant. The authors present a caseof one of these participants to highlight thepotential use of an FM system as analternative treatment option for those whomight not wish to undergo surgicalimplantation or for whom surgicalimplantation is contraindicated.

BACKGROUND INFORMATION

In February 2000, SG (some guy), a 79-year-old male, was seen at the Bay Pines

VAMC. SG was a seasonal resident of Florida,as are many of the patients seen at Bay PinesVAMC. SG had a history of military noiseexposure, with records indicating he was lastfit binaurally with Oticon Multifocus® behind-the-ear (BTE) hearing aids in 1997 at aNorthern VAMC. SG was referred to the BayPines VAMC audiology clinic by his primarycare provider because of a “failure of his hearingaids to work properly.” Audiometric dataindicated a severe-to-profound sensorineuralhearing loss (see Figure 1) with poor word-recognition scores in quiet, that is, 25% for the right ear and 0% for the left ear.Air-conduction thresholds and word-recognition scores in quiet were consistentwith the audiometric testing completed in1997. SG reported his primary communicationgoal for hearing aid use,as determined throughthe Client-Oriented Scale of Improvement(COSI; Dillon et al, 1997), was to hear betterone-on-one in quiet. Although when first seenin our clinic, SG met audiometric criteria forconsideration as a candidate for a cochlearimplant, records do not indicate that this optionwas discussed at the time.

In March 2000, SG was fit binaurallywith Phonak PowerZoom® BTE hearing aidswith a DHC-2® remote control. Clinicalprotocol involved fitting hearing aids to NAL-R (National Acoustic Laboratories—Revised)prescription (Byrne and Dillion, 1986) withverification of fit using real-earmeasurements. Both hearing aids wereprogrammed for use in quiet on Program 1,

Figure 1. Pure-tone air-conduction thresholds for the right and left ear obtained in February 2000 and March 2003.


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use in mild noise on Program 2, and moderatenoise on Program 3. For Programs 2 and 3, theAudioZoom® feature of his hearing aids wasturned on, which activated the fixedhypercardioid directional microphones andreduced the low-frequency gain. Based on hishighly elevated auditory thresholds and poorword-recognition skills in quiet, SG wascounseled regarding realistic expectations forcommunication, such as the limitations ofconventional amplification when listening inless than optimal conditions (e.g., backgroundnoise, large distance from speaker, lack ofvisual cues). Attendance of a Hearing LossEducation (HLE) class offered at Bay PinesVAMC was also recommended for SG and hisspouse. The curriculum for the HLE classincluded instruction on the functional effectsof hearing loss, instruction and role-playing oncommunication strategies for both the personwith hearing loss and his or her significantother with normal hearing, and counselingon the importance of both the listener withhearing loss and his or her primarycommunication partner changing maladaptivecommunication behaviors that do not facilitateeffective communication. Finally, SG wascounseled that he might be a candidate for acochlear implant, but no referrals for a CIevaluation were made at that time.

In May 2000, SG was seen for a routinepost-hearing-aid-fitting follow-up appointmentin which it was determined that his goal hadbeen satisfactorily achieved. Specifically, SGindicated that he could communicateeffectively with his wife at home as long asvisual cues were available.

SG returned to the North and was notseen again in our clinic until October 2000.During this visit, SG reported that whenlistening in Program 1 (quiet program), thevolume was too loud. In addition, he reportedthat noise was bothersome. Overall gain wasreduced in Program 1, and it was determinedthat both microphones on each hearing aidwere clear of debris. If debris is blocking,even partially, one of the microphones in adual microphone system as used in thePowerZoom, the directionality can benegatively impacted as a result of microphonemismatch. SG was reminded of thelimitations with conventional amplificationfor an individual with his degree of hearingloss. Cochlear implantation, as an option,was presented again, and SG was encouragedto explore information about the benefits andlimitations of cochlear implantation.

Two weeks later (November 2000), SGreturned to the clinic, this time reportingdifficulty understanding speech in noisybackgrounds. After determining that bothmicrophones were clear of debris, adjustmentsto the frequency responses in Programs 2and 3 were made by reducing gain in the lowfrequencies and increasing gain in themidfrequency regions. Between December2000 and February 2001, SG was seen anadditional three times, each time with asimilar report that Program 2 and Program3 were not beneficial in noisy situations.Minor adjustments were made to thefrequency response, and additional counselingwas provided in each session. SG returned tohis summer home up North and was not seenagain until November 2001.

Between November 2001 and April 2002,SG was seen four times in the Hearing AidRepair Clinic by an experienced audiologytechnician to address reports that hearingaids were not working appropriately. Thetechnicians made minor programmingadjustments and physical modifications onthe basis of subjective report (real earmeasures are not used by the audiologytechnicians in our clinic to verify the resultsof programming changes).After spending thesummer months up North, SG returned to theHearing Aid Repair clinic in November 2002,not only complaining about the functioningof his hearing aids but reporting a noticeabledecrease in his overall hearing ability. SGwas referred for a comprehensive audiologicalreevaluation.

PRE-FM FITTING AUDIOLOGICALASSESSMENT

SG was seen for the audiological evaluationin early March 2003. During the

evaluation, SG reported that his ability tounderstand speech had declined and that hewas experiencing extreme difficultycommunicating in all situations, especially ingroup situations with background noise. SGexpressed frustration with his currentcommunication ability and was interestedin any hearing device that might improvehis ability to communicate even ifimprovement was minimal.

Results from audiometric testing showeda 10–15 dB decrease in air-conductionthresholds since his previous examinationin 2000 (see Figure 1). After reviewing test


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results, the possibility of cochlearimplantation was again discussed. SG said hehad explored cochlear implants and was notinterested in undergoing surgery. As theauthors were currently recruitingparticipants for the FM research study, theprotocol was described to SG, and he agreedto participate. In addition to enrolling SGinto the study, the audiologist decided toreplace the three-year-old Phonak PowerZoomBTE hearing aids with a new set of the samemake and model instruments. While theaudiologist could have chosen to use newtechnology (i.e., digital hearing aids), there wasno clinical advantage to be achieved withdigital signal processing for this patient. SGwas proficient in the operation of his currenthearing aids; the electroacoustic properties ofthe PowerZoom instruments were appropriatefor the degree of impairment; the PowerZoominstruments were compatible with PhonakMicrolink® FM system use, and mostimportantly, SG expressed a great desire to trythe FM system as soon as possible. If thehearing aid technology was changed, the studyprotocol would have required at least a one-month trial period with new hearing aidsprior to FM use.

INITIAL STUDY VISIT

SG enrolled in the study at the end ofMarch 2003. The purpose of the initial

study visit was twofold.The first objective wasto verify that the participant’s current hearingaids were functioning and programmedappropriately. Since SG’s hearing aids hadjust been checked, and new instrumentsordered, this was not done. The secondpurpose of this visit was to establish specificgoals for FM use utilizing COSI and to obtainbaseline measures for selected items fromthe Communication Profile for the HearingImpaired (CPHI; Demorest and Erdman,1987) and MarkeTrak survey (Kochkin, 1990)with reference to use of hearing aids alone.

Goals for FM Use

The COSI was designed as a goalattainment scaling tool to be used by theclinician to identify important individuallistening situations that are pertinent to aspecific patient. Once identified, theindividual listening situations becomecommunication goals to be achieved through

treatment with amplification and/or anassistive listening device such as an FMsystem. During the initial visit, SG was askedto identify three main listening situationsin which he wanted to improve his ability tocommunicate through the use of an FMsystem. The main communication goal forSG was to be able to understand his wife ina one-on-one situation (i.e., in the kitchen,riding in the car, taking walks together). Hissecond communication goal was to improvehis ability to hear his friends in a one-on-onesituation at a restaurant during Friday nighthappy hour. His third goal was to improve hisability to understand on the telephone.

SG was asked to rate his “final ability”with his hearing aids (i.e., how much of thetime he could communicate effectively in thesituations he nominated as treatment goals),by choosing from five options: “hardly ever”(10%), “occasionally” (25%), “half of the time”(50%), “most of the time” (75%), and “almostalways” (95%). SG reported that with hiscurrent Phonak PowerZoom BTE hearingaids, he was able to understand his wife only50% of the time, communicate effectively athappy hour only 25% of the time, andunderstand on the phone 10% of the time.Typically, patients are asked to note their“degree of change” from no hearing aids to useof hearing aids as either “worse,” “no change,”“slightly better,” “better,” or “much better.”This was not measured in the study due tothe long-term use of hearing aids prior tohis initial study visit.

Baseline Outcomes Data

CPHI

The CPHI is a 145-item questionnaireassessing self-perception of communicationperformance, communication importance,communication environment, communicationstrategies, and personal adjustment. Anadvantage of the CPHI is that it providescomprehensive information about the effectsof hearing loss on an individual’s functioning.A disadvantage, particularly from a clinicalperspective, is the length of administrationtime. For the purposes of this clinicalinvestigation, the authors decided to use onlythe 18 items related to self-perception ofcommunication performance. These itemsprovide five scale scores. Three of the scalesassess communication effectiveness in

different types of situations—social, work,2and home. The other two scales assesscommunication effectiveness as a functionof type of listening condition—Average andAdverse. For each item, SG indicated whetheror not he could communicate effectively byusing a 5-point response scale ranging from1 for “Rarely or Almost Never” to 5 for“Usually or Almost Always.” The scores SGreported for each of the CommunicationPerformance scales using hearing aids aloneare shown by the black bars in Figure 5. Allscale scores were close to 2, which indicatedthat with hearing aid use alone, SG, onaverage, perceived his communication to beeffective only “Occasionally or Sometimes”across the various situations andenvironments.

MarkeTrak Survey

Items that appeared relevant to FM aswell as hearing aid use were selected from theMarketrak Hearing Aid Owner survey.Several of the selected items related to overallsatisfaction, hours of device use, overallquality of life, and negative feelings of

embarrassment, ridicule, or rejection. Theresponses obtained for hearing aid use aloneare shown in the second column of Table 1.SG reported he was “neutral,” neithersatisfied or dissatisfied with his currenthearing aids, wore them about 16 hours a day,that the hearing aids “sometimes” improvedhis quality of life, and that he “never” hadnegative feelings regarding hearing aid use.

Another set of questions from Marketrakassessed satisfaction with device featuresand functioning in different listeningsituations (see Table 2). SG indicated hislevel of satisfaction using a 5-point scale,ranging from 1 for “Very Dissatisfied” to 5 for“Very Satisfied.” As can be seen in the secondcolumn of Table 2, SG appeared relativelysatisfied with the hearing aid features butrelatively dissatisfied with how the hearingaids functioned, particularly in noise andwith soft sounds.

Responses by SG to questions aboutsatisfaction with hearing aid use in a varietyof listening situations and how important itwas for him to hear well in each of thesesituations is shown in Table 3. The secondcolumn shows the baseline data obtained for


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Table 1. Responses to Questions from Marketrak Survey for Items Related to Overall Satisfaction, Use,Overall Quality of Life, and Negative Feelings

Item HA Alone FM Six Weeks FM One Year

Overall Satisfaction Neutral Very Satisfied Very Satisfied

Hours of Use 16 12–16 12+

Quality of Lifeimprovement due to Sometimes Most of time Most of time device use

Feeling embarrassed,Ridiculed, or rejected due Never Never Neverto device use.

Table 2. Satisfaction with Device Features and Functioning

Feature HA Alone FM Six Weeks FM One Year

Visibility to others 4 5 5

Clearness of tone and sound 3 4 4

Reliability 4 5 5

Improves your hearing 4 5 4

Use in noisy situations 2 4 3

Ability to hear soft sounds 2 3 4

Comfort with loud sounds 3 3 4

Note: Responses were on a 5-point scale: 1 = Very Dissatisfied, 2 = Dissatisfied, 3 = Neutral, 4 = Satisfied, and 5 = Very Satisfied.


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listening with hearing aids alone. Thesatisfaction ratings, obtained using a 5-pointscale, with 1 for “Very Dissatisfied” and 5 for“Very Satisfied,” are shown first, followed bya number in parentheses, which indicates theimportance rating.The importance rating wasobtained using a 4-point scale with 1 for “NotImportant” and 4 for “Very Important.” SGwas not satisfied with his hearing aids in anyof the listening situations, and he indicatedthat being able to hear in all of the situationswas at least “somewhat important.” Note thatSG indicated there was only one situation inwhich it was “Very Important” for him to hearwell.This was “Conversation with one person,”for which he indicated he was “Dissatisfied”with the use of hearing aids.

The last MarkeTrak question asked SG toindicate the degree of change he hadexperienced, since he had started using thedevice (i.e., hearing aids), in a variety ofdifferent areas related to quality of life.Theseareas are shown in the first column in Table4, and his responses for hearing aids alone inthe second column.The data show no areas forwhich hearing aids resulted in an improvementin perception. For example, SG reported thatmental ability, feelings about himself, andsense of safety were “the same” with hearingaids as without hearing aids. His mental andemotional health and confidence in himself andhis ability to participate in group activitieswere all perceived to be “somewhat worse”with hearing aids than without.

Table 3. Satisfaction with Devices in Specific Listening Situations

Situation HA Alone FM Six Weeks FM One Year

Conversation with one person 2 (4) 5 (4) 4 (3)

In small groups 1 (3) 4 (3) 4 (3)

Outdoors 2 (3) 3 (2) 4 (3)

In large groups 1 (3) 3 (0) 2 (1)

At a concert/movie 1 (3) NR (0) NR (0)

Riding in a car 3 (3) 4 (2) 3 (2)

On the telephone 1 (3) 3 (3) NR (0)

Listening to music 1 (3) NR (0) NR (0)

In a place of worship 1 (2) NR (0) NR (0)

In a restaurant 2 (2) 4 (2) 4 (1)

Leisure activities 3 (2) 4 (2) 4 (3)

Note: Responses were on a 5-point scale: 1 = Very Dissatisfied, 2 = Dissatisfied, 3 = Neutral, 4 = Satisfied, and 5 = Very Satisfied. NR= no response. Numbers in parenthesis indicate how important SG reported it was to “hear well” in each situation. Responses were on a 4-point scale: 1 = Not Important, 2 = Somewhat Important, 3 = Important, and 4 = Very Important. A “0” indicates that an importance ratingwas not given.

Table 4. Changes SG Believed Occurred as a Result of Device Use

Area HA Alone FM Six Weeks FM One Year

Mental/emotional health 2 4 4

Mental ability 3 3 3

Physical health 3 3 3

Relationships at home 2 5 5

Social life 2 3 4

Feelings about yourself 3 3 3

Ability to participate in group activities 1 4 4

Sense of independence 2 5 4

Sense of safety 3 3 3

Confidence in yourself 2 3 3

Note: Responses were on a 5-point scale: 1 = A lot worse, 3 = The same, 5 = A lot better. No terms were provided for 2 or 4.

STUDY VISIT 2

The purpose of the second study visit wasto fit the FM device and provide general

training in the use of the FM system andspecific training related to the first goal forFM use as determined through COSI. Inaddition, SG was fitted with the new set ofPhonak PowerZoom hearing aids with a DHC-2 remote. For the FM system, SG was fit withPhonak MLx® receivers (Figure 2) bilaterallyand a Phonak HandyMic® transmitter(Figure 3), which is a handheld transmitterthat can also be worn on a lanyard. To fit theFM devices, the hearing aid response wasfirst compared to the NAL-R insertion gaintarget (Byrne and Dillon, 1986). RMS (rootmean square) difference between the NAL-R target and real ear insertion gain (REIG)with a 65 dB SPL composite noise input wasless than 5 dB from 500–2000 Hz bilaterally.Next, the FM transmitter was placed 15 cmfrom the real-ear system speaker, and thehearing aid and FM receiver were set to the“FM only” mode. A 65 dB SPL compositesignal was presented, and the REIG asprocessed through the FM system wascompared to the REIG of the hearing aid.The purpose of the verification was to assurethe FM system was providing a smooth andappropriate frequency response when coupledto the hearing aid. This procedure alsoallowed for verification that equal gain was

present for the FM-only and hearing aid-only modes by observing a higher SPL for theFM-only REIG (due to the microphone 15cm from the speaker) than the hearing aidREIG (microphone at 1 m from the speaker).

Once the fitting was verified, SG wasprovided instructions on the general use of theFM system. This included how to couple theFM system to the hearing aids, the variousprograms available through the hearing aidremote and through the FM receivers, thetransmitter settings, and how to charge theFM transmitter battery. After this generalinstruction, SG was provided with specificinstructions and practice using the FMsystem to improve communication with hiswife in one-on-one listening situations. SGwas accompanied by his wife to this sessionso that she could learn appropriate use of thetransmitter. The audiologist demonstratedhow to select the appropriate settings on thetransmitter, receivers, and the hearing aidremote control. SG and his wife engaged inseveral role-playing activities to practiceswitching from hearing aid use alone to FMuse alone to hearing aid and FM usecombined. In addition, SG was provided ahandout with step-by-step instructions forsetting up the FM system for one-on-onesituations. He was also given quick-referenceinstruction cards to carry in his pocket.


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Figure 2. MLx® wireless FM receiver coupled to aPowerZoom BTE hearing aid. Figure 3. HandyMic® FM transmitter.


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STUDY VISIT 3

The next visit for SG occurred two weeksfollowing the FM fitting. The purpose of

the third study visit was to introduce a newgoal for FM use and to monitor progress andreinforce the first goal. SG indicated that hewas benefiting from FM use whencommunicating with his wife and daughterin one-on-one situations. He reported someconfusion regarding how to set the systeminto FM-only mode, so re-instruction wasprovided. SG was then instructed on how touse the FM system most effectively to reachhis second communication goal, that is,improved communication with friends athappy hour on Friday nights. Once again,SG received verbal instructions, handoutswith step-by-step instructions for activatingthe FM system for small group in noisesituations, instruction cards to carry in hispocket for quick reference, hands-ondemonstrations, and role-playing in asituation similar to a happy hour setting.

STUDY VISIT 4

After an additional two weeks of practice,SG returned for his fourth study visit. By

this time, SG had mastered the use of theHandyMic transmitter and was reportingbenefit and success with his first twocommunication goals. For his thirdcommunication goal, that is, improvedtelephone communication, an additionaltransmitter, TelCom® (Figure 4), was neededto connect to the telephone.The TelCom is anFM transmitter that connects to both thetelephone and an audio signal such as the

television that allows for convenient switchingbetween the telephone and audio device, sothat when the FM system is broadcastingan audio signal, the TelCom sends thetelephone ring through the FM system tothe hearing aid. When an FM user answersthe telephone, the TelCom automaticallymutes the audio signal and transmits thetelephone signal through the FM receivers.The volume of the television or radio is notaltered for others in the room. When thetelephone handset is replaced, the audiosignal transmitted to the hearing instrumentsis turned back up to the previous volumesetting. If the FM user answers the phone andthe call is intended for someone else, the usercan override the TelCom and reengage theaudio signal, allowing the other person totalk on the phone in private. SG practicedanswering a telephone connected to a TelComand was provided with written instructionsto follow at home over a final two-week periodof time.

FINAL STUDY VISIT

During the final study visit, SG was askedto indicate his “final ability” and “degree

of change” for each COSI goal, completeselected items from the CPHI and Marketrakquestionnaires with a focus on FM use,indicate how much he would be willing to payfor an FM system if one were to be purchased,and finally, to decide whether or not he wishedto continue using the FM system beyond thestudy protocol. The report by SG of his goalattainment and data collected from selectedoutcome measures are described.

Figure 4. TelCom® FM transmitter.

Goals of FM Use

In terms of the first COSI goal identifiedby SG, improved communication with hiswife, SG reported he could communicateeffectively “95% of the time,” and he alsoreported the degree of change from hearingaid use to hearing aids plus an FM system tobe “much better.” During communicationsituations involving happy hour (i.e., the secondgoal), SG reported that he could communicateeffectively “50% of the time” and also thatcommunication during happy hour was “muchbetter” with the FM system than with hearingaids alone. For his final communication goal,improved telephone communications, SGreported that he was only able to communicateon the telephone “occasionally” but that it was“better” with the addition of the FM system.Given SG’s auditory word-recognition ability,the ability to “occasionally” to communicatevia hearing alone on the telephone was a veryencouraging finding. In face-to-facecommunication, SG was able to use bothauditory and visual cues to understandmessages. On the telephone, without visualcues, it would be expected that communicationwould be much more difficult for SG.

Outcomes Data

CPHI

Responses for the CommunicationPerformance scales are shown by the diagonalbars in Figure 5. The responses given by SGindicated improvement in self-perception ofcommunication effectiveness on all subscales.In fact, except for the work subscale, all of theincreases exceeded the 90th percentileconfidence intervals reported by Erdman andDemorest (1990) for a clinically significantchange. The greatest improvement was forcommunication at home. This result isconsistent with the treatment emphasis givento the first COSI goal reported by SG,communicating in one-on-one situations withhis wife.

MarkeTrak

Responses to MarkeTrak survey itemsare shown in column 3 of Tables 1–4. Asindicated in Table 1, overall satisfaction withthe FM system was high, and SG reported hewas using the FM system at least 12 hours

a day. He reported his quality of life wasimproved “most of the time” due to FM systemuse and that he had no negative feelingsassociated with FM use. As with hearingaids, satisfaction with device features washigh (Table 2), and in contrast to hearing aidfunctioning, with which SG was not satisfied,he was now “satisfied” with “use in noisysituations” and now “neutral” with regard to“ability to hear soft sounds” and “comfortwith loud sounds.”

When SG was asked to indicatesatisfaction with FM use in specific listeningsituations (Table 3), further validationregarding his communication goal ofimproved communication in one-on-oneconversations was obtained. He indicatedthat he was “very satisfied” with FM use inthis situation. High levels of satisfaction werefound for several other situations—-smallgroups, riding in a car, in a restaurant, andleisure activities. As might be expected fromthe COSI data, SG indicated that he was“neutral” with regard to satisfaction withFM use on the telephone.This finding was notsurprising, however, because SG had verypoor auditory speech recognition ability.Neutral responses were also obtained forlistening outdoors and in large groups.Although SG initially indicated that listeningat concerts/movies, listening to music, andlistening in places of worship were at leastsomewhat important to him prior to the FMtrial period, he did not provide a satisfactionrating for these situations. It is not knownwhy ratings were not provided by SG. Severalpossibilities exist. First, it may be that he had


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Figure 5. Scores for Communication Performancesubscale of the CPHI.


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no experience in any of the situations or thatthey were no longer perceived to be important.Indeed, when asked to rate his self-perceivedimportance, he left these items blank. Second,another possible explanation is that SG didtry the FM system in these situations andfound them to be frustrating. In this case, SGmay have in essence “given up” the idea ofhearing well in such situations. A thirdpossible reason for the lack of responses tothese items may have been due to a greaterneed for counseling on FM use in the specificlistening situations. For example, when anFM system is used in a place of worship, itis important that the microphone be placedon or near the talker or that the microphonebe connected through the direct audio inputcable to the sound system. The latter wouldalso be important in concerts or movies, ifavailable. While this information was givento SG, it is not known if he remembered tofollow the instructions. Similarly, whenlistening outdoors, different recommendationsare made based on whether the specificactivity involves listening at a near versus fardistance or in a fixed versus a mobilesituation. SG did not provide any specificoutdoor listening goals; thus, this area wasnot fully explored during follow-up, andspecific directions were not given. Finally, asseen in Table 4, SG indicated hismental/emotional health, relationships athome, ability to participate in group activities,and sense of independence were all better asa result of FM use.

Willingness to Pay

While clinical outcome measures revealcritical information concerning benefit,additional information concerning how muchan individual values a service or device canbe obtained through a willingness-to-pay(WTP) question (Palmer et al, 1995; Chisolmand Abrams, 2001). As with the otherparticipants in the FM study, the authorsasked SG how much more (using a retailvalue of $4,000 for the hearing instrumentsalone as an anchor) he would be willing to payfor the FM transmitter and receivers giventhe benefits achieved with his FM system.Although eligible veterans are not requiredto pay out of pocket for hearing aids or FMsystems, SG provided a WTP value of $3000.Although this does not mean that SG wouldhave paid this amount, it does suggest thatSG perceived the value of an FM system to

be relatively high compared to the value ofhearing aids. That is, the FM system wasworth 75% of the cost of hearing aids.

Decision to Keep FM

SG elected to keep his FM system. Hisfinal study visit was in May of 2003. SG didnot contact the audiology clinic again untilMay of 2004, at which time he reported thathis hearing aids and FM system were notperforming as well as when first received.During this visit, the audiologist replacedthe tubing on both earmolds, which hadbecome hard and brittle, and reviewed theimportance of using the transmitter close tothe mouth of the speaker to improve thesignal. SG reported the hearing aid soundquality was much improved with the newtubing, and he was satisfied with theperformance of the FM system again as well.

Soon after the May 2004 visit, SG, aswell as all other participants, was sent follow-up CPHI and MarkeTrak study questions.The purpose was to determine which, if any,of the positive outcomes observed at the endof the FM study trial period were maintained.The gray column in Figure 5 shows the one-year responses for the CPHI subscales.Whilethere were decreases from six weeks post for all scales, none of these decreases exceeded the 90% confidence intervals for a clinically significant change. It is somewhat disappointing that self-perceivedcommunication performance for all scalesmeasured in this study on the CPHI from pre-FM to one-year post–FM fitting wereminimal. Since no objective testing wascompleted at one-year post–FM fitting, it isnot clear if the relatively small changes incommunication performance are due to aninitial overinflation of benefit due to theHawthorne effect or to a change in hearingstatus and/or device function.

With regard to MarkeTrak, the resultingdata for the one-year follow-up are shown inthe last column in Tables 1–4. SG reported nochanges in overall satisfaction and use afterone year of FM use as compared to six weeksof FM use (Table 1). Similarly, as seen inTable 2, SG reported no changes insatisfaction of device features and functioningafter one year of use as compared to six weeksof FM use, except for use in noise, which aftersix weeks, SG reported being “satisfied” with,but after one year, SG reported being “neutral”(neither satisfied nor dissatisfied). With

regard to satisfaction in specific listeningsituations (Table 3), SG reported a slightdecrease at one year as compared to six weekspost–FM use for three of the 11 situations: (1)conversation with one person (very satisfiedto satisfied), (2) in large groups (neutral todissatisfied), and (3) riding in a car (satisfiedto neutral). Improvements noted after sixweeks in terms of mental health,relationships, participation, and sense ofindependence were maintained after oneyear. In addition, SG reported improvementin his social life as a result of FM use at oneyear (Table 4).

SUMMARY AND CONCLUSIONS

The case of SG is representative of manypatients who seek audiologic care at the

VA. Patients with significant hearing lossmay have experienced reasonable successwith hearing aids in the past, but as they ageand their hearing loss progresses, the benefitsof conventional amplification becomeincreasingly limited. As a result, patientswith significant hearing loss often makemultiple visits to the clinic for replacementhearing instruments or to make repeatedadjustments to their current instruments toresolve growing problems with speechintelligibility, particularly in adverse listeningenvironments. Similar to SG, many of thepatients with significant hearing loss assumetheir hearing aids “aren’t working right.” Atsome point, the clinician becomes aware thatconventional amplification will no longermeet the communication needs of the patientregardless of technology and that a decisionneeds to be made to pursue alternatives toamplification; for many patients, the optionof choice is cochlear implantation. As isillustrated in this case, however, not allpatients are agreeable to the implant optionand, given results for SG on the COSI, CPHI,MarkeTrak, and WTP, a convincing case canbe made that FM technology is a viable andeffective alternative to cochlear implantation.It is particularly important to note that theself-perception of benefit by SG as measuredby the MarkeTrak questionnaire remainedfairly stable for most situations over thecourse of 12 months.

Given the potential for good clinicaloutcomes with FM, a cost-effectivenesscomparison between CI and FM cannot beignored.The cost to the VA for two digital BTEinstruments, two receivers, one transmitter,

and a remote control is approximately $2,900as compared to an implant cost of about$23,000. The cost difference in the privatesector is likely to be even greater (even withthe higher FM device costs) given the surgeonand hospital fees associated with the CIprocedure. Several of the participants in ourstudy who initially requested evaluation foran implant were so pleased with the FMresults that they no longer wished to beconsidered for an implant. Of course, theauthors do not know if SG’s outcome wouldhave been better with a cochlear implant,but that he is satisfied enough with theresults of his FM system to continue to refusereferral for a CI suggests that any additionalbenefit would not have been “worth the cost.”In fact, FM receivers are manufacturedspecifically for cochlear implants, suggestingthat the problem of understanding speechin adverse listening environments continuesto remain a problem for many CI users.

The authors believe similar success withFM technology can be achieved with otherpatients exhibiting severe-to-profoundhearing impairment providing two importantrules are followed. First, the clinician andpatient must identify specific situations notbeing met with conventional hearing aids, andthe clinician must determine if the identifiedsituations can be reasonably achieved withFM technology. The authors found the COSIto be a particularly effective tool for thispurpose. Second, the patient must be carefullyfollowed through regular and frequent follow-up visits, particularly among older patientswho may feel overwhelmed with thetechnology (transmitters, receivers, adaptors,shoes, telephone devices, etc.). The authorsalso found it important to address onecommunication problem at a time (startingwith the highest priority problem) and toensure the patient was comfortable with thetechnology in this situation before moving onto the next.

In summary, the results of this case studymay be interpreted to suggest that FMtechnology can be a reasonable alternative tocochlear implantation for some subset ofveterans with significant hearing loss, interms of both clinical outcomes and cost-effectiveness. Given the success achieved bySG, clinicians may want to reconsider theirprotocols when treating patients with severe-to-profound hearing impairment to include atrial with FM technology prior to referral forCI evaluation.


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NOTES

1. Additional implantations were likely performedat universities with sharing agreements with thenearby VA Medical Centers, but as these affiliationsare not recognized as VA CI Centers, the number ofthese cases is unknown to national program officialsand therefore not captured for statistical purposes.2. As detailed in the CPHI manual, subjects who didnot work were asked to consider a comparablesituation for the items describing work environments.

Acknowledgment. This work was supported byPhonak, Inc.We would like to thank Amanda Hemardand Richard Wilson for their assistance in this proj-ect.

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Noe CM, McArdle R, Chisolm TH, Koder K, Rost L,Hemard A,Wilson RH,Abrams H, Reese J. (2004) FMtechnology use in adults with significant hearing lossI: candidacy. In: Fabry D, Johnson CD, eds. ACCESS:Achieving Clear Communication Employing SoundSolutions. Proceeding for the First International FMConference. Great Britain: Cambrian Printers,113–119.

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