In-FORM-ation for Better Patient Care, Part 2: Another Look at the Standard “Audiogram Form”

In a recent article¹ in HR, I promoted the idea that we should all be constantly asking ourselves, “Why am I doing this test for this patient, and why am I doing it in this order?” If our answer is “Because that’s the way I was taught to do it” or “That’s the way I’ve always done it,” then it is time to revisit our rationales and try to objectively determine if this approach is the best one. The article then went on to address the Patient History Form—an important tool used in dispensing offices for screening patients for “red flags” that would warrant immediate referral to a physician. Additionally, the patient history and its related form should provide you with a reasonable “first look” or estimation of the patient’s degree and slope/configuration of hearing loss, nature of the loss (conductive, sensorineural, or central), and its impact on the individual.

Similar to Part 1 on Patient History Forms, this article concerns itself with the “Audiogram Form” (which generally also includes other audiometric tests). One salient point is that your test battery should have a logical and appropriate order so as to contribute to the gestalt of your and your staff’s hearing assessment, while providing for an optimal patient experience, with a logical “flow” that minimizes movement and/or switching settings on their part. It is important to keep in mind that patients age 65 or older have on average 30-45 minutes of high quality attention time; you need to the pertinent information in this time.

Jay B. McSpaden, PhD, CCC-A, BC-HIS, is an audiologist who retired from private practice and currently works part-time as a hearing instrument specialist in Jefferson, Ore.

In this discussion, one should be aware that insurance companies have forms that vary and evolve; likewise, any practitioner has his/her own work flow and perferred tests. Therefore, the information presented here is not intended to be didactic; it is “food for thought” for comparing your own current test battery and reporting system.

Brief Overview of the Audiogram Form

The Audiogram Form (Figure 1) used in our practice is a single two-sided sheet on which we have the ability to make statements about the patient’s general auditory system function. The upper third of the form contains the identifying information, including our practice logo, location, and contact information. At the top left is the patient’s name, age, date, address, the referral source, as well as the patient’s physician and phone number. Finally, the audiometer make and model are listed.

The middle-third of the front side is used to contain a right and left audiogram. We insert all the appropriate marks and symbols into and on this audiogram form. It is important to have a separate space for information generated from the data on both right and left ear.

Below this is a summary of the results divided into two sides. On the right-hand side below the “Figure Legend” is the set of symbols used in the form. At the center in the bottom third are five lines in which a brief preliminary report can be written.

On the back side of the Audiogram Form is the tympanometric data for the right and left ears. There are also spaces for the ipsilateral reflex data, contralateral reflex measurement, reflex decay information, and a Sensitivity Prediction by Acoustic Reflex (SPAR) test (performed if necessary). Additionally, there is a space for the patient’s name, the date, and the examiner’s name (important should this be the only testing procedure performed and/or if only the back of the form needs to be copied).

The bottom half of this back side of the Audiogram Form is used for “half lists” of the CID W-22 word lists. They are provided so that either “recorded” or “live voice” Word Discrimination Test scores can be generated using masked monosyllabic words. These are not the only lists available, but they are the ones currently used in our clinic.

The contents of the back of our form are copied “head to toe” because they are “pinned” into the chart at the top center. We can just turn up the page and read the results of the audiometric test battery used as appropriate for individual patients (Table 1).

FIGURE 1A and 1B. The front (left) and back (right) of our office’s Audiogram Form. We actually copy the back of the form (second page) in a “head-to-toe” fashion so that tympanometric data on the back of the form can be quickly added to the front. Full-size versions of this form are available as downloadable pdfs – just click on the images above.

Using the Form: Starting at the Back with Impedance Testing

After taking the Patient History¹ and performing otoscopy, we start at the back of the form (Figure 1b) with the tympanometric boxes. These are marked off in cc’s of equivalent volume and have a scale along the abscissa of mm of water pressure, with a range of +300 mm of water pressure to -300 mm water pressure and from 0.2 to 2.6 cc of equivalent volume along the ordinate or “Y” axis. Also along the ordinate, about one-third of the way from the top, is a “time marked” section that is 14 seconds long. This can be used with a printer for acoustic reflex decay measurements.

In our clinic, these data are generated manually and then transcribed onto the right and left Audiogram Form at the appropriate units of volume and pressure. The points measured are then connected so as to describe the right and left tympanograms at the correct units of pressure and volume.

Acoustic reflex threshold measurements are made from contralateral presentations of the signal through the earphone. These are measured through the probe tip in the contralateral ear. The threshold measurements are reported on the form under that ear into which the signal is inserted.

The ipsilateral measurements are always written on the side into which the signal was delivered. If reflex decay procedures are performed, they start at 1000 Hz with contralateral presentation. This is at the threshold for the reflex plus 10 dB for 10 seconds. If the results of the reflex change fall 50% or less in the steady state during the 10 seconds, the results are “positive” for “reflex decay.” If this is the case, a test is run at 500 Hz looking for the same response.

TABLE 1. Summary of the audiometric test battery presented in this article and its coverage of different sites of lesion.

On the other hand, if there is less than 50% decrease or no decrease when the stimulus is presented at threshold plus 10 dB for 10 seconds, the results are said to be “negative” for involvement of the VIIIth cranial nerve. In this case, the 500 Hz test is not performed.

The Audiogram Form is then turned back over (to the front of the form), and this data is summarized on the actual audiogram. The data for the right ear are recorded on the right side and those for the left are recorded on the left, placing an R or an L with a circle around them at the appropriate frequency and intensity. This permits us to see the recruitment at frequency as the “reflex threshold” approaches the “hearing threshold” within 65 dB. For example, if the reflex was measured to be 85 dB at 1000 Hz, an “R” with a circle around it would be entered at 85 dB on the 1000 Hz line of the appropriate ear.

We repeat this process at 500 Hz, 2000 Hz, and 4000 Hz for each ear specifying the measured thresholds at the correct frequencies. In the event that there is no response at a frequency, we leave that space blank. These measurements always refer to contralateral reflexes. When there are none but an ipsilateral reflex is present, this is shown as an “R” with a circle and the notation “Ipsi.”

On the “Summary of Results,” there is a space for “Tympanogram Type.” In this space goes either A or a subset of A, B, or C. (For a basic review of tympanometry, see McSpaden.²) Below that is a block to indicate the results of “Reflex Decay” testing. We view that as positive, negative, or blank. Positive reflex decay is a possible indicator of involvement of the VIIIth cranial nerve.

Tests in the Sound Booth

Speech MCL. The patient is then placed in a sound-treated room, and a number of tests are preformed. The first procedure is for the elicitation of the Most Comfortable Level (MCL) for speech, the results of which are noted in the summary. In addition, a bar about two-thirds as wide as the two adjacent intensity lines is placed between 500 and 2000 Hz at the measured level with”MCL” written in it. The measurement is done ipsilaterally in each ear and then bilaterally. This number is written as a fraction of Right/Left (as X/Y) in the MCL box marked “bin.”

Word recognition/speech reception testing with masking. The next procedure is the Speech Recognition Test (SRT) or Word Reception Test using either an ascending or descending presentation method. One can do this using the standard CID W-1 word lists in a “live voice” or via recording. The elicited SRT (or WRT) is entered into the summary.

This is followed by the Performance-Intensity Phonetically-Balanced (PI-PB) test, which is a version of the speech (or word) discrimination test. This yields the maximum potential score for “phonetically balanced” words (the so-called PBmax). It is also the score elicited at a maximum level of 90 dBHL, which allows us to look for the possibility of PI-PB rollover—an indicant of possible VIIIth nerve involvement. Again, these tests can be done using recorded presentation or by live voice.

Before we leave this brief discussion of procedures, it is necessary to say that, in our clinic, all speech discrimination testing is done using masking in the non-test ear. The masking signal is a white noise, and it is usually presented in the following manner:

1. If the otoimmittance indicates that the hearing loss is sensorineural, the presentation level of the masking is inserted at a level of 10 dB below the presentation level of the speech in the non-test ear.
2. If the otoimmittance indicates that the hearing loss is determined to be conductive, the masking level used in the non-test ear is 10 dB above the presentation level of speech in the test ear.

QuickSIN. The QuickSIN is an easy-to-use series of sentences recorded in four-talker babble, representing a realistic simulation of a social gathering in which the listener may “tune out” the target talker and “tune in” one or more of the background talkers. QuickSIN scores are reported in SNR loss and can provide insight into what type of amplification, if any, is applicable to the patient (directional microphones, array microphones, FM systems, etc).

Puretone testing. When all of the procedures involving speech are complete, the next procedures involve puretones. These are measured in the standard manner beginning at 1000 Hz in the “better ear” or the “right ear” (if there is no preference). The procedure is essentially the Hughson-Westlake procedure modified by Jerger and Carhart—a standard method for more than 40 years. Once the threshold measurements have been made and entered onto the right and left audiograms, several decisions need to be made.

If the interaural attenuation could be overcome, masking will have to be used before the puretone air conduction measurements are complete. In this case, we use narrow-band masking with an audiometer producing “frequency following” masking signals. We use the Hood Plateau Method for all puretone masking.

Following this task, another decision must be made: whether tone decay testing is necessary. If tone decay is indicated (or ordered by the physician), we use the Olsen-Noffsinger³ version of the test. The form for this can be found under the right-hand portion of the “Summary of Results.” This version of the test is performed at threshold plus 20 dB for 60 seconds. If, at the end of the 60 seconds, the hand is still raised or the button still depressed, the test results are said to be “negative” for involvement of the VIIIth cranial nerve. If the hand is “lowered” or the button released before the end of the 60 seconds, the results are said to be “positive.”

In our clinic, we take this test one step further; we do the test at higher frequencies, up through 4000 Hz, at which the threshold for hearing is not 80 dB or worse. In this way, we will not present a puretone at 100 dB at any frequency to any patient in either ear. We begin the test at this highest frequency knowing that, if the results at this high frequency are “negative,” the likelihood of a “positive” at a lower frequency is minimal. We can therefore “‘abort” the test procedure. If the results are “positive,” we can continue at successively lower frequencies until we reach a “negative” result or we have gone below 1000 Hz.

At this point, in the spirit of doing everything that requires earphones before removing them, we decide whether a “central battery” or a “central screening” is necessary (Table 1). We may do it now or we may reschedule the patient to return at a later time for the performance of the central battery. Any central test that we do is listed on the blank lines at the bottom. The name of the test, the results of the test, and the interpretation of these results are listed on a separate line of the Audiogram Form. A statement about the “site of lesion” responsible for these results is also included.

Before we remove the headset to introduce the bone oscillator, we make a careful inspection of the relation between the threshold of hearing and the acoustic reflex threshold level. At any time that the relationship gets within 60 dB at the same frequency, it is clear that “recruitment” has to have occurred. That is not to say that the reflex procedure is a test of recruitment; it is not! The only true test of recruitment is a “loudness balancing” procedure, such as that of Fowler et al since the brain makes judgments of loudness. These judgments of “perceived loudness” require roughly 85 dB in the normal-hearing ear. Whenever these thresholds approximate each other by less than 65 dB, the difference must have been “recruited.” The closer the approximation is (which has a minimum of 25 dB), the greater the amount of recruitment.

Regardless of the absolute numbers, whenever there is an acoustic reflex and a puretone threshold at the same frequency (presented contralaterally), the brain perceives that approximately 85 dB of loudness has been introduced! It is important that this information be visibly available not only for the examiner but also for the referral source or physician. It is easy to see that the relationship for the threshold of hearing and the acoustic reflex threshold levels are such that “recruitment” is possible and that it is present. This is an important factor in the diagnosis of “central auditory pathology” and in differentiating that from “peripheral auditory pathology.”

We are all aware that “recruitment” is caused by changes in the cyto-architecture of the hair cells in the cochlea. A recruiting ear—particularly a “recruiting” ear without tone decay, reflex decay, or PI-PB rollover—is highly indicative of sensory pathology involving the cochlear structures.

It is valuable to indicate that, while these pathologies are not amenable to surgical remediation or treatment, they are exquisitely amenable to remediation. This can include the use of appropriately fit hearing instruments and/or other rehabilitative steps. Also pertinent at this juncture is an examination and comparison of the speech reception threshold (SRT) and the average of the best two of the “speech frequencies” (500 Hz, 1000 Hz, and 2000 Hz). The literature suggests that the best predictor of the SRT is the average of the best two of the three speech frequencies ±2 dB. However, since we make our measurements in 5 dB steps, the best two scores ±5 dB is within parameters.

Tone MCLs and UCLs: Before we remove the headset from the patient, if they are going to be a candidate for amplification, we make two other tone measurements: the Most Comfortable Loudness (MCL) and the Uncomfortable Loudness Level (UCL or LDL). We use the narrow bands of noise at the frequencies 2,000, 3,000, 4000, and 6,000 Hz in each ear and binaurally.

These measurements are made in a “conservative” manner with the patient identifying the comfortable level and uncomfortable level of each ear. Our experience is that UCLs have a very specific relationship (within about 5 dB) with acoustic reflex thresholds. That is as it should be since both are the point at which the ears “go nonlinear.”

We make these measurements for several reasons. Market data⁴ shows that unrecognized “tolerance problems” continue to be a major component in consumers’ dissatisfaction with hearing aids. In addition, we believe that loudness growth measurements are increasingly important as manufacturers continue to make aids that amplify above 3000 Hz. It is important that we keep in mind both the MCL and UCL limits. We do not want to inadvertently fit patients with an instrument that is too loud or must be “turned down” in order to be tolerated.

Bone conduction testing. Having now completed the measurements that require earphones, we remove them and fix the bone conduction oscillator onto the skull over the appropriate mastoid. We use an earphone over the “non-test” ear through which we can introduce “masking.” We do not conduct unmasked bone conducted measurements. The interaural attenuation for bone signals is 0 dB, so we use the “plateau” method (the same as we do with aid conduction testing). Finally, we are aware that there is a central masking effect, which elevates the masked threshold by about 5 dB. We subtract the 5 dB from the masked threshold to improve the accuracy of the measurements and use the symbols for masked bone conduction at 500, 1000, 2000, and 4000 Hz.

We are aware of a difficulty that occurs occasionally with bone conduction testing and air conduction threshold measurements at the same frequencies, in the same ears, and in the presence of sensorineural losses identified by otoimmittance. This difficulty is acquiring bone conduction results that are below air conduction results on the audiogram. The cardinal rule is “There is no such thing as accurate unmasked bone conduction testing.” Many of these difficulties are related to “placement” of the oscillator, sequelae of the mastoid bone, and sebaceous oils of the mastoid, etc. Bone conducted measurements are also highly subject to “artifact.”

The fact is this: in our clinic, we do the bone conduction procedure because it is required by law and because it verifies/cross-checks our impedance data. Once all of these procedures are completed, we remove the oscillator from the bone, the earphones from the head, and have the patient relax while the report is written.

Report Description

The preliminary report describes the degree of loss, the slope of loss, the configuration of the loss, and the nature of the loss by ear. In our clinic, we add a few sentences about the impedance results because they facilitate understanding on the part of the “end user” (physician). This helps to clarify the basis upon which the judgements were made.

The SOAP (Subjective, Objective, Assessment, Plan) format is approved by the Joint Commission on Accreditation of Healthcare Organizations and is the format with which physicians are most familiar. Using this format requires that you relay information in short succinct descriptors.

The Subjective portion can include information about your and the patient’s observations on hearing, vertigo, tinnitus, pain, drainage, etc—a subjective description of the problem, if any. The Objective part says that a “copy of the results is appended for the record,” and these records are careful to mention any involvement of the VIIIth cranial nerve. This is also the place to mention any indications for central auditory processing disorders.

The Assessment part of the document is a statement about “what the results mean” regarding the site or focus of lesion identified through the evaluation. There may be more than one site and each must be identified. An important distinction is that we do not report what is the problem; instead, we report where lesions are and the impact of such a lesion on the communicative abilities of the patient.

Within the Assessment, the locations of the pathologies identified are reported as “These findings are consistent with the probability of … [either cochlear pathology or any other specific site of lesion].”

Finally, the Plan portion consists of recommendations for the patient and these should be numbered sequentially. If a referral to a physician is involved, this is always #1. In our clinic, a typical plan might call for:

1. Wear ear protective devices whenever the patient anticipates being in the presence of noise.
2. Have at least a 30-day trial with binaural amplifying devices.
3. Have hearing re-evaluation on (at least) an annual basis or at any time there is the subjective impression of change in the status of their auditory system.

This format is easy to use and provides for brevity, clarity, and completeness. In our view, when combined with the complete test results and Patient History,¹ this provides an excellent record of patient encounters.

References

1. McSpaden JB. In-FORM-ation for better patient care, Part 1: A look at the Patient History Form and how it might be used more effectively. Hearing Review. 2010;17(10):14-24.
2. McSpaden JB. Basic tympanometry in the dispensing office. Hearing Review. 2006;13(12):28.
3. Olsen W, Noffsinger D, Kurdziel S. Acoustic reflex and reflex decay. Arch Otolaryngol. 1975;101:622-625.
4. Kochkin S. MarkeTrak VIII: Consumer satisfaction with hearing aids is slowly increasing. Hear Jour. 2010;63(1):19-32.

Correspondence can be addressed to HR or Jay B. McSpaden, PhD, at.