Effects of Infrasound Exposure on Measures of Endolymphatic Hydrops

NCT03132961 | Terminated

• 1 other identifier: 1701M04145
• Study Type: observational
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

Persons exposed to infrasound - frequencies below 20 Hz - describe a variety of troubling audiovestibular symptoms, but the underlying mechanisms are not understood. Recent animal studies, however, provide evidence that short-term exposure to low frequency sound induces transient endolymphatic hydrops. The existence of this effect has not been studied in humans. The long-term objective of this research is to identify a possible mechanism to describe the effects of infrasound on the human inner ear. The central hypothesis of the proposed study is that short-term infrasound exposure induces transient endolymphatic hydrops in humans. This will be tested by performing electrophysiologic tests indicative of endolymphatic hydrops among normal hearing individuals before and immediately after a period of infrasound exposure. Recordings of infrasound generated by wind turbines in the field have been established and calibrated by this team of engineers, otologist, and hearing and balance scientists. An infrasound generator reproduces the acoustic signature based on these field recordings. Aim 1: Determine the effect of infrasound on the summating potential to action potential (SP/AP) ratio on electrocochleography (ECoG). Hypothesis 1: Infrasound exposure will cause a reversible elevation of the SP/AP ratio. Aim 2: Determine the effect of infrasound on the threshold response curves of ocular and cervical vestibular evoked myogenic potentials. (oVEMP and cVEMP). Hypothesis 2: Infrasound exposure will cause elevation of the oVEMP and cVEMP thresholds at the frequency of best response. Successful completion of the aims will provide evidence for a possible mechanism of the effect of infrasound on the inner ear. This understanding will benefit individuals exposed to environmental infrasound and those in regulatory, research, and advocacy roles when crafting interventions and future policy.

Conditions

Vestibular Abnormality; Endolymphatic Hydrops

Keywords

Vestibular evoked myogenic potentials; Electrocochleography; Infrasound

Outcome Measures

Primary Outcomes (3)

• Measure the effects of infrasound exposure on the SP/AP ratio of electrocochleography

  A baseline ECoG recording will be obtained and the waveform's SP/AP ratio will be calculated and recorded (time "-10"). A 10-minute infrasound stimulus will ensue. Immediately following cessation of the stimulus (time 10), a repeat ECoG test run will be performed. A 10-minute recovery period will take place followed by a final ECoG test run (time 20). S/P ratios will be recorded for each test run and percent change will be calculated.

  Test measurements at time -10, 10, and 20 minutes

• Measure the effects of infrasound exposure on the threshold tuning curve of cVEMP

  A baseline cVEMP tuning curve will be obtained and recorded (time "-10"). A 10-minute infrasound stimulus will ensue. Immediately following cessation of the stimulus (time 10), thresholds will be repeated. A 10-minute recovery period will take place followed by a final threshold measurement (time 20). Thresholds will be recorded for each test run and average change in threshold in dB will be calculated.

  Test measurements at time -10, 10, and 20 minutes

• Measure the effects of infrasound exposure on the threshold tuning curve of oVEMP

  A baseline oVEMP tuning curve will be obtained and recorded (time "-10"). A 10-minute infrasound stimulus will ensue. Immediately following cessation of the stimulus (time 10), thresholds will be repeated. A 10-minute recovery period will take place followed by a final threshold measurement (time 20). Thresholds will be recorded for each test run and average change in threshold in dB will be calculated.

  Test measurements at time -10, 10, and 20 minutes

Study Arms (6)

Block 1

Participants in the cohort will undergo testing in the order of: ECoG, oVEMP, cVEMP

Other: Infrasound exposure

Block 2

Participants in the cohort will undergo testing in the order of: ECoG, cVEMP, oVEMP

Other: Infrasound exposure

Block 3

Participants in the cohort will undergo testing in the order of: oVEMP, cVEMP, ECoG

Other: Infrasound exposure

Block 4

Participants in the cohort will undergo testing in the order of: oVEMP, ECoG, cVEMP

Other: Infrasound exposure

Block 5

Participants in the cohort will undergo testing in the order of: cVEMP, ECoG, oVEMP

Other: Infrasound exposure

Block 6

Participants in the cohort will undergo testing in the order of: cVEMP, oVEMP, ECoG

Other: Infrasound exposure

Interventions

Infrasound exposure OTHER

All cohorts will receive an identical infrasound exposure of equal time duration, varying only the order in which the testing is performed. To simulate the frequencies generated by a common source of environmental infrasound (wind turbines), recordings measured at a full-scale research wind turbine at the University of Minnesota will be utilized to create an infrasound stimulus. The resultant sound file consists of the fundamental frequency at approximately 0.7 Hz, equal to the blade passage rate, plus the harmonic overtones of the fundamental frequency. The presentation level is 85 dB SPL. The stimulus will be presented in a sound field.

Block 1; Block 2; Block 3; Block 4; Block 5; Block 6

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

This study will be conducted in normal hearing adults. Each prospective participant will undergo a screening evaluation to determine eligibility, including: 1) completion of a basic otologic symptom questionnaire; 2) otoscopic examination; 3) binaural air conduction audiometry (250 to 1000 Hz).

You may qualify if:

• Age of 18 to 60 years
• Absence of otologic symptoms based on screening questionnaire
• Normal otoscopic examination
• Audiometric thresholds less than 25 dB at 250, 500, 750, 1000 Hz.

You may not qualify if:

• Presence of any positive symptom on the questionnaire
• Thresholds greater than 25 dB at the tested frequencies
• Abnormal otoscopic examination (e.g., ear canal occlusion, tympanic membrane perforation, tympanic membrane retraction)
• History of prior ear surgery.

Sponsors & Collaborators

• University of Minnesota: lead

Study Sites (1)

University of Minnesota

Minneapolis, Minnesota, 55455, United States

Location

Related Publications (28)

• Salt AN, Hullar TE. Responses of the ear to low frequency sounds, infrasound and wind turbines. Hear Res. 2010 Sep 1;268(1-2):12-21. doi: 10.1016/j.heares.2010.06.007. Epub 2010 Jun 16.

  PMID: 20561575 BACKGROUND

• Berglund B, Hassmen P, Job RF. Sources and effects of low-frequency noise. J Acoust Soc Am. 1996 May;99(5):2985-3002. doi: 10.1121/1.414863.

  PMID: 8642114 BACKGROUND

• Sugimoto T, Koyama K, Kurihara Y, Watanabe K. Measurement of infrasound generated by wind turbine generator. In: Proc. SICE Conf. 2008, pp. 5e8.

  BACKGROUND

• Orrell A, Foster N. 2015 Distributed Wind Market Report. U.S. Department of Energy; 2016.

  BACKGROUND

• Schmidt JH, Klokker M. Health effects related to wind turbine noise exposure: a systematic review. PLoS One. 2014 Dec 4;9(12):e114183. doi: 10.1371/journal.pone.0114183. eCollection 2014.

  PMID: 25474326 BACKGROUND

• Kageyama T, Yano T, Kuwano S, Sueoka S, Tachibana H. Exposure-response relationship of wind turbine noise with self-reported symptoms of sleep and health problems: A nationwide socioacoustic survey in Japan. Noise Health. 2016 Mar-Apr;18(81):53-61. doi: 10.4103/1463-1741.178478.

  PMID: 26960782 BACKGROUND

• May M, McMurtry RY. Wind Turbines and Adverse Health Effects: A Second Opinion. J Occup Environ Med. 2015 Oct;57(10):e130-2. doi: 10.1097/JOM.0000000000000447. No abstract available.

  PMID: 26461874 BACKGROUND

• McCunney RJ, Mundt KA, Colby WD, Dobie R, Kaliski K, Blais M. Wind turbines and health: a critical review of the scientific literature. J Occup Environ Med. 2014 Nov;56(11):e108-30. doi: 10.1097/JOM.0000000000000313.

  PMID: 25376420 BACKGROUND

• Flock A, Flock B. Hydrops in the cochlea can be induced by sound as well as by static pressure. Hear Res. 2000 Dec;150(1-2):175-88. doi: 10.1016/s0378-5955(00)00198-2.

  PMID: 11077202 BACKGROUND

• Salt AN. Acute endolymphatic hydrops generated by exposure of the ear to nontraumatic low-frequency tones. J Assoc Res Otolaryngol. 2004 Jun;5(2):203-14. doi: 10.1007/s10162-003-4032-z.

  PMID: 15357421 BACKGROUND

• Salt AN, Lichtenhan JT, Gill RM, Hartsock JJ. Large endolymphatic potentials from low-frequency and infrasonic tones in the guinea pig. J Acoust Soc Am. 2013 Mar;133(3):1561-71. doi: 10.1121/1.4789005.

  PMID: 23464026 BACKGROUND

• Hensel J, Scholz G, Hurttig U, Mrowinski D, Janssen T. Impact of infrasound on the human cochlea. Hear Res. 2007 Nov;233(1-2):67-76. doi: 10.1016/j.heares.2007.07.004. Epub 2007 Jul 29.

  PMID: 17761395 BACKGROUND

• Dommes E, Bauknecht HC, Scholz G, Rothemund Y, Hensel J, Klingebiel R. Auditory cortex stimulation by low-frequency tones-an fMRI study. Brain Res. 2009 Dec 22;1304:129-37. doi: 10.1016/j.brainres.2009.09.089. Epub 2009 Sep 28.

  PMID: 19796632 BACKGROUND

• Coats AC. The summating potential and Meniere's disease. I. Summating potential amplitude in Meniere and non-Meniere ears. Arch Otolaryngol. 1981 Apr;107(4):199-208. doi: 10.1001/archotol.1981.00790400001001.

  PMID: 7213179 BACKGROUND

• Durrant JD, Dallos P. Modification of DIF summating potential components by stimulus biasing. J Acoust Soc Am. 1974 Aug;56(2):562-70. doi: 10.1121/1.1903291. No abstract available.

  PMID: 4414701 BACKGROUND

• Seo YJ, Kim J, Choi JY, Lee WS. Visualization of endolymphatic hydrops and correlation with audio-vestibular functional testing in patients with definite Meniere's disease. Auris Nasus Larynx. 2013 Apr;40(2):167-72. doi: 10.1016/j.anl.2012.07.009. Epub 2012 Aug 4.

  PMID: 22867525 BACKGROUND

• Iwasaki S, Smulders YE, Burgess AM, McGarvie LA, Macdougall HG, Halmagyi GM, Curthoys IS. Ocular vestibular evoked myogenic potentials in response to bone-conducted vibration of the midline forehead at Fz. A new indicator of unilateral otolithic loss. Audiol Neurootol. 2008;13(6):396-404. doi: 10.1159/000148203. Epub 2008 Jul 29.

  PMID: 18663292 BACKGROUND

• Rauch SD, Zhou G, Kujawa SG, Guinan JJ, Herrmann BS. Vestibular evoked myogenic potentials show altered tuning in patients with Meniere's disease. Otol Neurotol. 2004 May;25(3):333-8. doi: 10.1097/00129492-200405000-00022.

  PMID: 15129114 BACKGROUND

• Winters SM, Berg IT, Grolman W, Klis SF. Ocular vestibular evoked myogenic potentials: frequency tuning to air-conducted acoustic stimuli in healthy subjects and Meniere's disease. Audiol Neurootol. 2012;17(1):12-9. doi: 10.1159/000324858. Epub 2011 Apr 29.

  PMID: 21540585 BACKGROUND

• Koerner TK, Zhang Y, Nelson PB, Wang B, Zou H. Neural indices of phonemic discrimination and sentence-level speech intelligibility in quiet and noise: A mismatch negativity study. Hear Res. 2016 Sep;339:40-9. doi: 10.1016/j.heares.2016.06.001. Epub 2016 Jun 4.

  PMID: 27267705 BACKGROUND

• Leventhall G. What is infrasound? Prog Biophys Mol Biol. 2007 Jan-Apr;93(1-3):130-7. doi: 10.1016/j.pbiomolbio.2006.07.006. Epub 2006 Aug 4.

  PMID: 16934315 BACKGROUND

• Duck FA. Medical and non-medical protection standards for ultrasound and infrasound. Prog Biophys Mol Biol. 2007 Jan-Apr;93(1-3):176-91. doi: 10.1016/j.pbiomolbio.2006.07.008. Epub 2006 Aug 4.

  PMID: 16965806 BACKGROUND

• Bonucci AS, Hyppolito MA. Comparison of the use of tympanic and extratympanic electrodes for electrocochleography. Laryngoscope. 2009 Mar;119(3):563-6. doi: 10.1002/lary.20105.

  PMID: 19235755 BACKGROUND

• Densert B, Arlinger S, Sass K, Hergils L. Reproducibility of the electric response components in clinical electrocochleography. Audiology. 1994 Sep-Oct;33(5):254-63. doi: 10.3109/00206099409071885.

  PMID: 7818379 BACKGROUND

• Blakley BW, Wong V. Normal Values for Cervical Vestibular-Evoked Myogenic Potentials. Otol Neurotol. 2015 Jul;36(6):1069-73. doi: 10.1097/MAO.0000000000000752.

  PMID: 25839981 BACKGROUND

• Piker EG, Jacobson GP, McCaslin DL, Hood LJ. Normal characteristics of the ocular vestibular evoked myogenic potential. J Am Acad Audiol. 2011 Apr;22(4):222-30. doi: 10.3766/jaaa.22.4.5.

  PMID: 21586257 BACKGROUND

• Adams ME, Heidenreich KD, Kileny PR. Audiovestibular testing in patients with Meniere's disease. Otolaryngol Clin North Am. 2010 Oct;43(5):995-1009. doi: 10.1016/j.otc.2010.05.008.

  PMID: 20713239 BACKGROUND

• Janky KL, Shepard N. Vestibular evoked myogenic potential (VEMP) testing: normative threshold response curves and effects of age. J Am Acad Audiol. 2009 Sep;20(8):514-22. doi: 10.3766/jaaa.20.8.6.

  PMID: 19764171 BACKGROUND

MeSH Terms

Conditions

Endolymphatic Hydrops

Condition Hierarchy (Ancestors)

Labyrinth Diseases; Ear Diseases; Otorhinolaryngologic Diseases

Study Officials

• Meredith E Adams, MD

  Assistant Professor

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 9, 2017
• First Posted: April 28, 2017
• Study Start: May 5, 2018
• Primary Completion: August 23, 2018
• Study Completion: August 23, 2018
• Last Updated: October 18, 2018

Record last verified: 2018-10

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)