Week 2, Spring 2008

This week, I saw a 20 year old college student who indicated that he has had difficulty processing auditory information in the classroom since enrolling in college. He reported a history of reading problems as a child. A neck surgery, due to an infection in the muscle, was noted, but no other outstanding medical history was provided.

Ear canals were clear, and tympanic membranes were visible and intact bilaterally. Tympanometry revealed normal, Type A, results bilaterally; however, the left TPP was slightly negative. Acoustic reflexes were normal for both ipsilateral and contralateral stimulations bilaterally.

Pure tone audiometry revealed normal thresholds at all test frequencies. Speech recognition thresholds were 15 dB HL bilaterally and were in good agreement with pure tone averages. When performed at 30 dB SL, word recognition scores were excellent, at 100%, bilaterally.

For the APD evaluation, the SCAN-A, the Auditory Fusion Test-Revised (AFT-R), and Staggered Spondaic Word Test (SSW) were administered. The SCAN-A is a screening measure that taps into many different types of processing. The AFT-R is a temporal processing test, and the SSW is a dichotic listening test that requires binaural integration. The client was normal on all test measures and did not exhibit any patterns on the chosen tests that suggested an APD. However, the client still reported difficulty understanding orally-presented information, particularly when background noise was present. These complaints occurred with normal hearing and no obvious APD.

Strange you say?!???!

That's what I thought too ... I found an article that represented a syndrome that causes problems that are similar to my client's complaints. The following article, Distortion Product Otoacoustic Emissions in Patients with King-Kopetzky Syndrome, by Fei Zhao and Dafydd Stephens details a comparison of a control group and a group with suspected King-Kopetzky syndrome.

http://web.ebscohost.com/ehost/pdf?vid=7&hid=107&sid=57c0ad2a-5431-4a2d-bd6d-82ab981bccc1%40sessionmgr102

http://web.ebscohost.com.www.libproxy.wvu.edu/ehost/pdf?vid=4&hid=106&sid=55fb21cd-5a39-4c5b-b0a2-4842d09d2093%40sessionmgr108

King-Kopetzky syndrome (KKS) is thought to be a multifactorial disorder with possible autosomal dominant inheritance. The chief complaint of those with KKS is hearing difficulties, particularly in noise, in the presence of normal pure tone thresholds. Although those with KKS have "normal" hearing, the test group in this study have thresholds averaged over 0.5 - 4 kHz that are significantly worse than age/sex-matched normals. Psychological factors, such as anxiety and depression, psychoacoustical factors, such as peripheral or central HL, and hereditary factors, such as family history and late-onset, dominant genetic inheritance may all contribute to KKS. The authors noted that KKS is present in 1% of ENT clinic patients complaining of problems with their ears or hearing and in 5-10% of those reporting hearing problems at audiology clinics.

This study used 35 males and 35 females ages 16-50 with one person per gender for each calendar year. All subjects had normal hearing, defined as thresholds better than or equal to 20 dB HL between 250 and 4000 Hz in the poorer ear. No threshold between 250 & 8000 Hz could be poorer than 30 dB HL. No other obvious signs of difficulty or signs of conductive pathology could be present. The control group had no recent hearing problems, and the KKS group had recently sought help for hearing difficulties, particularly understanding speech in noise.

TEOAE, DPOAE, and SOAE testing was performed. For TEOAEs, BB nonlinear clicks of 77 dB SPL (+/- 3 dB) were used. Clicks were presented for 80 usec at a rate of 50 clicks/sec. Responses were found when 260 sweeps were averaged with 50% or better reproducibility. A 0.5-6 kHz pass-band was used, and responses greater than or equal to 3 dB above the noise floor were considered "passes." When a statistical significance level of 0.05 was used, a significant difference was found when the normal responses of the control group (96%) and the KKS group (77%) were compared.

For DPOAEs, an f2/f1 ratio of 1.22 was used, and L1 = L2 = 70 dB SPL. Higher intensity levels were used because TOAEs were absent for many of the subjects in the KKS group. The response at 2f1 - f2 was analyzed. The global mean levels of the DPOAEs were significantly lower in the KKS group, and mid-frequencies (1.398-5.582 kHz) were most negatively affected.

Lastly, SOAE testing was performed, and fewer SOAEs were found in the KKS group.

This study indicated that a decrease in DPOAEs in the KKS groups from ~1-6 kHz (with the exception of 4 kHz) may indicate an area of minor dysfunction of the OHCs. Consideration of DPOAEs, case history, and probable subcategories of KKS may guide rehabilitation. (The subcategories are as follows: 1)ME dysfunction, 2)mild cochlear pathology, 3)central/medial olivocochlear efferent system auditory dysfunction, 4)purely psychological problems, 5)muliple auditory pathologies, 6)combined auditory dysfunction & psychological problems, 7)unknown.) Finally, additional testing, medical, &/or psychiatri referrals may be needed if patients seemingly have normal peripheral and central hearing, but persistently claim to have difficulty with speech in noise.

Although I did not do DPOAE testing with my client, that may be warranted in the future. However, when I saw him, I recommended compensatory classroom strategies, such as moving to the front of the room and asking for handouts of orally-presented material, to address his difficulties. I also recommeneded that he should seek additional disability services in our University's Disability Services Office.