1. An Audiologic Evaluation of Patulous Eustachian Tube
Kristine Sonstrom, MS
Graduate Seminar, Spring 2015

2. Patulous Eustachian Tube (PET)
Definition: Fairly uncommon condition of persistently patent (open) Eustachian tube, causing excessive communication between middle ear cavity and nasopharynx (McGrath & Michaelides, 2011) Prevalence: .3 to 10% of population (Henry & Bartolomeo, 1993), may be underestimated

3. Patulous Eustachian Tube
PET is a type of Eustachian tube dysfunction, along with other forms of dysfunction:
Reduced middle ear compliance
Middle ear effusion
Tympanic membrane retraction
Otitis Media
The above forms of middle ear dysfunction are obstructive, i.e. they obstruct or block the ET from the middle ear space
Often result in conductive hearing loss

4. Anatomy and Physiology
Eustachian tube (ET) connects middle ear space to nasopharynx, allowing for pressure equalization of middle ear space
Open during fetal development, after birth ET is normally closed
ET opens via dilatory muscles
Tensor Veli Palatine

5. Anatomy
Review anatomy
Image retrieved from dangerousdecibels.org

6. Etiology/ Associated Conditions
Etiology: Swelling of Eustachian tube, tonsil or adenoid tissues
Physical characteristics of ET and surrounding tissues often triggered by certain conditions (O’Conner & Shea, 1981; Henry & DiBartolomeo, 1993; Poe, 2007)
Pregnancy
Fatigue
Stress
Weight loss
Hormone and/or radiation therapy
Oral contraceptives
Protracted otitis media
Scarring or atrophy of nasopharynx

7. Common patient symptoms
Autophony
Unusually loud hearing of one’s own voice
Tinnitus
Popping, crackling
Respiratory-synchronous (occurring with each inspiration/exhalation)
Hyperacusis
Distortion
Pressure
Aural Fullness
Hearing loss

8. Common symptoms cont. Exacerbated by heavy breathing
Exercising
Symptoms subside or disappear when patient is lying down
Gravitational force
Symptoms may decrease with head between the knees

9. Differential Diagnosis
Obstructive forms of Eustachian tube dysfunction (i.e. otitis media)
Semicircular canal dehiscence
Meniere’s disease
Palatal myoclonus
Rapid rhythmic contractions of palate muscles (

10. Evaluation of PET Audiologic evaluation Immittance measures
Tympanometry
Acoustic Reflex Decay test
Parameters are different
Medical evaluation – Ear Nose and Throat

11. Case Study- Patient History
29 Year old female
Symptoms:
Aural fullness
Intermittent “clicking or popping” sound
Echoic feeling, she can hear herself breathing loudly (autophony)
Symptoms began following swimming incident
Her PCP previously reported otorrhea from left ear
Had tonsil-adenoidectomy as a child

12. Case Study- Evaluation
Otoscopy: Clear external auditory canal, healthy tympanic membranes, bilaterally
Tympanometry: Type A, normal middle ear pressure and compliance, bilaterally
Pure-tone Audiometry: Normal hearing sensitivity from Hz, bilaterally
Speech Audiometry: SRT: 0dB HL, WRT: 100% at 40 dB HL, bilaterally

13. Evaluation for PET: Immittance Testing
Tympanometry
ME compliance
Ear Canal Volume
Pressure of ME
Acoustic Reflex Decay
Set tympanometer to lowest auditory stimulus possible, so not to elicit acoustic reflex (typically dB HL), and set frequency to 500 Hz

14. Step-by-Step Assessment of PET
Place probe tip in ear
Run tympanometry
Select acoustic reflex decay
Decrease stimulus intensity to lowest level possible and select frequency of 500 Hz
Pressurize ear canal
Instruct patient:
Normal breathing, record ME compliance
Mouth breathing, record ME compliance
Nose breathing, record ME compliance
Ipsilateral nostril breathing (plug contralateral nostril), record ME compliance
Print and record results
Repeat test battery for other ear

15. Evaluation Instruction Continued
Clearly describe and demonstrate breathing tasks
Often the clinician performs the test simultaneously with patient during test
Instruct patient to breathe slowly, deeply and rhythmically, without heaving chest, shoulders, neck and head during breathing

16. Case Study- Results Tympanometry MEP (daPa) ECV (ml) Peak (ml)
Right ear 20
1.6
0.9
Left ear 10
1.1
Patulous Eustachian Tube Evaluation
Step
Right/Left
Middle Ear Compliance During Breathing (ml)
Respiratory-Synchronous Pattern of ME Compliance
Baseline
Right
.02 No
Mouth Only
.09
Nose Only
.10
Ipsi Nose Only
Left
.03
.26
Yes
.36
.55

17. Right Ear

18. Left Ear

19. What to look for… Positive test:
Higher compliance noted (i.e. above .07 ml***)
Compliance should change synchronously with patient respirations
If difficulty noticing synchronous pattern, have patient change rate of respiration’s mid-way through testing (i.e. breath slow then fast), and assess for synchrony
The condition which appears most likely in a respiratory-synchronous pattern is the ipsilateral nostril condition, however, the pattern has been observed in all conditions (McGrath & Michaelides, 2011).
***Use this as a general guideline, this can vary, and is based on a comparison between ears and the graphical result from the tympanometer (as in our case study, we are above .07 ml for the right ear, however the test is negative). Remember, PET is in its infancy.

20. Impressions and Plan Impressions: Plan:
Normal middle ear pressure and compliance, bilaterally
Normal hearing sensitivity, bilaterally
Negative PET on right
Positive PET on left
Plan:
Follow-up with ENT for medical recommendations and treatment

21. Challenges with testing
Patient may not exhibit symptoms during testing
Obtaining good hermetic seal with probe tip
May need to repeat testing while reinstructing patient
Evaluator needs to be able to differentiate between compliance changes with patient movement and compliance changes with synchronous respirations

22. Typical medical diagnosis and treatment?
Determined via nasal endoscopy
Nasal sprays to induce irritation of Eustachian tube mucous membranes, causing them to become more bulky, narrowing the passageway
Weight gain for those patients who have lost weight and developed symptoms of PET
Cartilage Eustachian tuboplasty, a corrective surgery in which surgeons use autograph cartilage to augment the walls of the Eustachian tube, narrowing the passageway

23. Conclusion
PET is uncommon, however, may be under-recognized in the common population
This case study sheds light into a rare yet occurring condition which can be easily assessed through immittance testing from the audiologic evaluation
***Audiologist note: Perform the testing to understand how to evaluate the patient. Interpretation can be challenging, especially with those “in-between” cases. Medical evaluation always occurs prior to treatment; we work in close collaboration with our ENT’s for the evaluation and diagnosis of PET

24. References
Henry, D.F. & DiBartolomeo, J.R. (1993) Patulous Eustachian tube identification using tympanometry. J Am Acad Audiol 4(1): 53-57
McGrath, A.P. & Michaelides, E.M. (2011) Use of Middle Ear Immittance Testing in the Evaluation of Patulous Eustachian Tube. J Am Acad Audiol 22:
O’Conner, A.F. & Shea, J.J. (1981) Autophony and the patulous Eustachian tube. Laryngoscop 91:
Poe, D.S. (2007) Diagnosis and management of the patulous Eustachian tube. Otol Neurotol 285: