Hearing/ET/Vestibular in Balloon Pilots (FLIGHT-EAR)

Hearing and Eustachian/Vestibular Functions in Hot Air Balloon Pilots: A Cross-sectional Matched-Control Study

This study looks at whether working as a hot-air balloon pilot-being exposed to burner noise, changes in air pressure/temperature, and vertical acceleration-is linked to changes in hearing, Eustachian tube function, and vestibular (balance) function. Adult pilots from Cappadocia will be compared with adults who do not have these exposures.

Approximately 90 participants are expected to be enrolled For contextual exposure information, representative in-field noise measurements during balloon operations and basic flight parameters may be documented

Each participant will attend one visit (~60 minutes) in an ENT/audiology laboratory. After a short questionnaire and an ear exam (otoscopy), the following non-invasive tests will be performed: tympanometry; tympanometry with simple maneuvers (Valsalva/Toynbee) to evaluate Eustachian tube function (ΔTPP); pure-tone audiometry (including extended high frequencies); otoacoustic emission tests (TEOAE and DPOAE); acoustic (stapedius) reflex thresholds; and a brief cervical vestibular evoked myogenic potential (cVEMP) test. Symptom-triggered questionnaires will also be used: for participants reporting tinnitus, the Tinnitus Handicap Inventory (THI); for those reporting dizziness, the Berg Balance Scale (BBS).

No medications or blood tests are involved. Testing is safe and routinely used in clinical care. Risks are minimal (for example, temporary ear-canal pressure or brief dizziness). Testing will be stopped if any discomfort occurs. Personal information will be kept confidential, and results will be reported only in group form. Findings from this study may help improve occupational health guidance for hot-air balloon pilots.

Study Overview

• Status: Completed
• Conditions: Vestibular Disorders; Occupational Exposure; Hearing Loss, Noise-Induced; Eustachian Tube Dysfunction
• Intervention / Treatment: Other: Non-invasive audiologic and vestibular assessments

Detailed Description

This study looks at whether working as a hot-air balloon pilot-being exposed to burner noise, changes in air pressure/temperature, and vertical acceleration-is linked to changes in hearing, Eustachian tube function, and vestibular (balance) function. Adult pilots from Cappadocia will be compared with adults who do not have these exposures.

Approximately 90 participants are expected to be enrolled For contextual exposure information, representative in-field noise measurements during balloon operations and basic flight parameters may be documented

Each participant will attend one visit (~60 minutes) in an ENT/audiology laboratory. This is a cross-sectional study with a single assessment visit. The following non-invasive tests will be performed

Tympanometry.

Acoustic (stapedius) reflex thresholds.

Tympanometry with simple maneuvers (Valsalva/Toynbee) to evaluate Eustachian tube function (pressure change in the middle ear) (ΔTPP).

Pure-tone audiometry (standard clinical frequencies and extended high frequencies).

Otoacoustic emission tests (OAE), including transient-evoked (TEOAE) and distortion-product (DPOAE), with analysis including high frequencies.

Cervical vestibular evoked myogenic potential (cVEMP) (a test of inner-ear balance reflexes), administered for all participants using a standardized protocol and EMG monitoring for adequate sternocleidomastoid activation.

Symptom-triggered questionnaires:

For participants reporting tinnitus, the Tinnitus Handicap Inventory (THI) will be administered.

For participants reporting dizziness, the Berg Balance Scale (BBS) will be administered.

Testing is non-invasive and performed in a sound-treated environment per routine clinical practice. If any discomfort (e.g., significant dizziness, pain, or elevated blood pressure) occurs, the relevant test is stopped and the participant may be withdrawn from testing at the investigator's discretion. For contextual exposure information, representative in-field noise measurements, air-pressure and altitude during balloon operations and basic flight parameters may be documented where available; these are not required for participation.

Data are recorded under coded study IDs and stored on secure institutional servers with access restricted to authorized study staff. Results will be reported in aggregate to protect confidentiality.

• Study Type: Observational
• Enrollment (Actual): 105

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye), 34108
    • University of Health Sciences, Gaziosmanpaşa Training and Research Hospital, Department of Otorhinolaryngology-Head & Neck Surgery (ENT/Audiology Laboratory)
  • Göreme
    • Nevşehir, Göreme, Turkey (Türkiye), 50200
      • Cappadocia Field Site (Göreme) - On-site assessments at hot-air balloon pilot companies

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Adults (≥18 years) in two cohorts: (1)(Hot-Air Balloon Pilots) licensed hot-air balloon pilots operating in the Cappadocia/Nevşehir region with ≥10 flights in the prior 12 months; and (2)(Controls) age-matched adults with no occupational or recreational exposure to significant noise, altitude, or barometric pressure variation (e.g., non-pilots, non-divers, non-cabin crew). Participants are healthy volunteers with otoscopic suitability (no perforation or active infection). Recruitment is via local pilot companies/registries and the surrounding community; all assessments occur at the SBÜ Gaziosmanpaşa Training and Research Hospital ENT/audiology laboratory (single-center). Planned enrollment: 45 pilots and 45 controls.

Description

Inclusion Criteria:

• Age ≥18 years (preferably 18-70).

Pilot group: Licensed, professional and actively flying hot-air balloon pilots with regular flight over the past 12 months (on average 5 days per week and at least 20 flights in month), not using any hearing-protection equipment, and typically each flying et least 60-90 minutes.

Control group: Adults without occupational or recreational exposure to significant pressure/altitude/noise (e.g., no mountaineering, scuba diving, or cabin crew duties).

Otoscopic suitability for testing (no tympanic membrane perforation; no active ear infection).

Exclusion Criteria:

• Acute upper respiratory tract infection (URTI) or otitis at the time of testing.,
• High noise exposure within the past 24-48 hours (e.g., concert, workshop).
• Tympanic membrane perforation; impacted cerumen that cannot be cleared; chronic suppurative otitis; presence of an active ventilation (tympanostomy) tube.
• History of otologic surgery.
• Menière's disease; significant otosclerosis; vestibular neuritis within the past 6 months; recent sudden hearing loss.
• Significant neurological disease or history affecting balance (e.g., multiple sclerosis, stroke).
• Use of ototoxic medications within the past 3 months (e.g., aminoglycosides, cisplatin).
• Contraindications to cVEMP testing (e.g., significant cervical pathology or prior cervical surgery, uncontrolled hypertension, suspected advanced carotid artery disease).

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Hot-Air Balloon Pilots; Licensed, professional and actively flying hot-air balloon pilots (≥18 years) with regular flight over the past 12 months (on average 5 days per week and at least 20 flights in month), not using any hearing-protection equipment, and typically each flying et least 60-90 minutes. Participants undergo a single non-invasive laboratory session including, tympanometry, tympanometry with maneuvers (Valsalva/Toynbee) for Eustachian tube function, pure-tone audiometry, otoacoustic emission (OAE) testing, acoustic reflex thresholds, and cervical vestibular evoked myogenic potential (cVEMP). No drugs, devices, or biospecimens are used.	Other: Non-invasive audiologic and vestibular assessments; standardized, single-session test battery performed in a sound-treated clinical laboratory. Procedures include tympanometry, tympanometry with simple maneuvers (Valsalva/Toynbee) for Eustachian tube function, pure-tone audiometry, otoacoustic emission (OAE) testing, acoustic reflex thresholds, and cervical vestibular evoked myogenic potentials (cVEMP) with EMG monitoring for adequate sternocleidomastoid activation. Testing is non-invasive, takes ~60 minutes, and is conducted under routine clinical practice conditions. No investigational drugs, devices, or biospecimens are used.; Other Names: Audiologic and vestibular test battery; Hearing and balance function tests; Audiologic evaluations; Vestibular assessments
Control Group; Age (≥18 years) without occupational or recreational exposure to noise, altitude, or barometric pressure changes. Participants undergo the same single non-invasive laboratory session as the pilot group (tympanometry, pure-tone audiometry, OAE tests, acoustic reflex thresholds, and cVEMP). No drugs, devices, or biospecimens are used.	Other: Non-invasive audiologic and vestibular assessments; standardized, single-session test battery performed in a sound-treated clinical laboratory. Procedures include tympanometry, tympanometry with simple maneuvers (Valsalva/Toynbee) for Eustachian tube function, pure-tone audiometry, otoacoustic emission (OAE) testing, acoustic reflex thresholds, and cervical vestibular evoked myogenic potentials (cVEMP) with EMG monitoring for adequate sternocleidomastoid activation. Testing is non-invasive, takes ~60 minutes, and is conducted under routine clinical practice conditions. No investigational drugs, devices, or biospecimens are used.; Other Names: Audiologic and vestibular test battery; Hearing and balance function tests; Audiologic evaluations; Vestibular assessments

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Eustachian Tube Function (ΔTPP after Valsalva/Toynbee)	Tympanometric middle-ear pressure change (ΔTPP in daPa) after maneuvers will be recorded. Impaired function defined as ΔTPP ≤15 daPa.	At baseline, single visit (~5 minutes)
Distortion Product Otoacoustic Emission (DPOAE) amplitudes at 1-12 kHz	Mean DPOAE amplitudes at 1-12 kHz will be compared between hot-air balloon pilots and controls. Lower amplitudes are hypothesized in pilots with greater flight exposure.	At baseline, single visit (~5 minutes)
Transient-Evoked Otoacoustic Emission (TEOAE)	Description: Mean TEOAE SNRs (dB) in half-octave bands from 1-4 kHz (and overall response/reproducibility %) will be compared between hot-air balloon pilots and controls. Lower SNRs are hypothesized in pilots with greater flight exposure.	At baseline, single visit (~5 minutes)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tympanometry middle-ear pressure (TPP) and compliance	Description: Tympanometric peak pressure (TPP, daPa) and middle-ear compliance (ml) values will be obtained and compared between hot-air balloon pilots and controls. Abnormal or more negative TPP values are hypothesized in pilots with greater flight exposure, indicating possible Eustachian tube dysfunction.	At baseline, single visit (~3 minutes)
Pure-Tone Audiometry thresholds	Air-conduction thresholds at standard clinical frequencies and high frequencies. Hypothesis: higher thresholds in pilots.	At baseline, single visit
Cervical Vestibular Evoked Myogenic Potential (cVEMP) parameters	cVEMP amplitude and latency measured bilaterally. Hypothesis: altered responses in pilots.	At baseline, single visit
Acoustic Reflex Thresholds	Lowest sound level (dB HL) eliciting stapedius reflex, when measurable.	At baseline, single visit
In-field noise metrics during balloon operation (exploratory)	LAeq, LAFmax, and LCpeak recorded for contextual analysis. During flight observations (subset only)	During balloon flight, single observation (~60-90 minutes)
Tinnitus Handicap Inventory (THI) score	Self-reported tinnitus-related handicap, total score (0-100).	Baseline, single visit
Berg Balance Scale (BBS) score	Self-reported balance function, 14-item scale (0-56).	Baseline, single visit

Collaborators and Investigators

• Sponsor: Gaziosmanpasa Research and Education Hospital
• Investigators: Principal Investigator: Ethem İlhan, MD, University of Health Sciences, Gaziosmanpaşa Training and Research Hospital (Istanbul, Turkey)

Publications and helpful links

General Publications

• Avci D, Sahin MI. Are the hearing and eustachian tube functions of the hot air balloon pilots disturbed? Auris Nasus Larynx. 2022 Aug;49(4):577-583. doi: 10.1016/j.anl.2021.11.002. Epub 2021 Nov 25.
• Sahin Ceylan D, Sacli Y, Gultekin G, Avsar B, Ozver AG. Do Flights Affect Hearing in Hot Air Balloon Pilots? Am J Audiol. 2023 Nov 22:1-10. doi: 10.1044/2023_AJA-23-00126. Online ahead of print.

Study record dates

Study Major Dates

• Study Start (Actual): September 4, 2025
• Primary Completion (Actual): October 20, 2025
• Study Completion (Actual): November 30, 2025

Study Registration Dates

• First Submitted: September 13, 2025
• First Submitted That Met QC Criteria: September 27, 2025
• First Posted (Actual): October 1, 2025

Study Record Updates

• Last Update Posted (Actual): January 21, 2026
• Last Update Submitted That Met QC Criteria: January 19, 2026
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: Hearing Loss; Occupational Health; Vestibular Function; Noise Exposure; Hot-Air Balloon Pilots; Eustachian Tube Function; cVEMP; Otoacoustic Emissions (OAE); Acoustic Reflex; Altitude / Barometric Pressure
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Otorhinolaryngologic Diseases; Sensation Disorders; Ear Diseases; Hearing Disorders; Hearing Loss, Sensorineural; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hearing Loss; Hearing Loss, Noise-Induced; Musculoskeletal and Neural Physiological Phenomena; Physiological Phenomena; Nervous System Physiological Phenomena; Sensation; Vestibulocochlear Physiological Phenomena; Hearing
• Other Study ID Numbers: Cappadoc-baloon-odio

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: No plan to share individual participant data (IPD). The informed consent and protocol do not authorize IPD sharing, and the cohort is small and identifiable (hot-air balloon pilots in a defined region), increasing re-identification risk. Per protocol, only aggregate, de-identified results will be reported; source data remain on secure institutional servers accessible only to the study team.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No