Hearing disorders review

1. Ozarks Technical Community College HIS 110 Hearing Disorders Review

2. Disorders of the Outer & Middle Ear Causes a conductive hearing loss (CHL) On the audiogram, you would find normal bone conduction thresholds and abnormal air conduction thresholds Tympanograms (test of middle ear function) will be abnormal

3. Conductive HL in Right Ear

4. Abnormal Tympanograms Type B=flat Type C=negative pressure

5. Abnormal Tympanograms Type A s =stiff, hypocompliant Type A D =flaccid, hypercompliant

6. Outer Ear Pathologies Anotia absence of the outer ear Microtia malformation of the outer ear Wax build-up Otitis Externa aka swimmer’s ear or outer ear infection (bacterial) Atresia absent or closed earcanal Stenosis narrowing of EAC Otomycosis fungal infection of EAC Exostoses bony growth in EAC, common in cold water swimmers Osteoma bony tumor in EAC

7. Microtia of Right Ear http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

8. Occluding Cerumen http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

9. Otitis Externa http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

10. Stenosis http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

11. Exotoses http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

12. Osteomas http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

13. Tympanic Membrane Pathologies Myringitis inflammation of TM Tympanosclerosis thickening and scarring of the TM Perforation hole or tear in the TM May be caused by fluid pressure due to otitis media, barotrauma (rapid pressure change due to flying or scuba diving), or self-inflicted (q-tip use)

14. Bullous Myringitis http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

15. Tympanosclerosis Hawkelibrary.com

16. TM Perforation Hawkelibrary.com

17. Middle Ear Pathologies Otitis media (OM) =middle ear infection Otitis media with effusion (fluid) May be acute (sudden onset) or chronic (long-lasting) Eustachian tube dysfunction malfunction of Eustachian tube Causes retraction of TM and popping, crackling, pressure, pain Patulous Eustachian tube Eustachian tube is stuck open (patent) Autophony, hearing one’s own voice in head, is common complaint Otosclerosis Bony growth over stapes footplate and fixation to oval window Ossicular chain discontinuity Loss of connection between the ossicles; usually due to head injury Cholesteatoma An erosive tumor composed of skin, protein, and fats

18. Serous Otitis Media http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

19. Cholesteatoma http://wps.prenhall.com/chet_martin_audiology_11/194/49689/12720513.cw/index.html

20. Treatment for Conductive HL Medical Antibiotic eardrops, oral antibiotics for bacterial infections Surgical Myringotomy (incision in TM), pressure-equalization tubes, ossicular repair, stapedectomy (removal of stapes and prosthesis placement) Amplification CHL is very easy to fit with a hearing aid(s) Because the sensory cells of the cochlea are healthy, CHL only requires amplification to power through the middle ear pathology. Once the sound gets past the middle ear problem, it is clearly transmitted through the remainder of the auditory system with ease.

21. Disorders of the Inner Ear Results in a (primarily) sensorineural hearing loss (SNHL) On the audiogram, you would find abnormal bone conduction and air conduction thresholds Tympanograms (test of middle ear function) will usually be normal

22. Bilateral SNHL

23. Normal Tympanogram Tests middle ear function = eardrum, ossicles, eustachian tube Measures changes in the movement of the eardrum Type A=normal

24. Inner Ear Pathologies Presbycusis Age-related hearing loss; effects the high frequencies first Noise-Induced Hearing Loss (NIHL) Exactly like it sounds; dependent on intensity, duration, and type of noise exposure, classic “noise notch” seen from 3 to 6 kHz, with recovery at 8 kHz Meniere’s disease Overacummulation of endolymph in the cochlea; characterized by attacks of vertigo, tinnitus (roaring), low-frequency SNHL (usually unilateral), nausea/vomiting Ototoxicity High-frequency SNHL due to damaging effects of certain drugs (most notably aminoglycoside antibiotics and platinum-based chemo drugs) Perilymph fistula Hole (fistula) at the oval window, in which perilymph leaks into middle ear. Fluctuating HL (SNHL or Mixed HL) and dizziness common. Superior Semicircular Canal Dehiscence Hole or thinning of the bony lining of the superior SCC; symptoms: fullness, autophony , dizziness with/sensitivity to loud sounds, low-frequency CONDUCTIVE hearing loss with normal tympanogram

25. Meniere’s Disease Cochlear Cross-Section *Note the displacement of the vestibular membrane due to the overabundance of endolymph in scala media Hawkelibrary.com

26. Ototoxicity Partial Loss of Outer Hair Cells Complete Loss of Outer Hair Cells One row of Inner Hair Cells unaffected 3 rows of outer hair cells Hawkelibrary.com

27. A note about sudden hearing loss Sudden, idiopathic sensorineural hearing loss is any SNHL that occurs very suddenly with no identifiable cause Usually unilateral May be partial or complete loss of hearing Often accompanied by dizziness and tinnitus Requires IMMEDIATE medical referral Do not assume that a patient has wax, an infection, or a broken hearing aid if they call complaining of a sudden inability to hear. If you can’t see them ASAP refer them to their primary doctor or an ENT for a same-day appointment, if possible. Steroid treatment that occurs within the first week of the hearing loss may result in improved/recovered hearing.

28. Treatment for SNHL Hearing Aids Hearing Assistive Technology Cochlear Implants

29. Mixed HL in the Right Ear Mixed hearing loss (MHL) is a combination of sensorineural hearing loss with a conductive HL component Commonly seen in older adults with presbycusis and middle ear disorder May be seen in cases of perilymph fistula, head injury, barotrauma Image from: asha.org

30. Treatment for MHL Because MHL is a combination of CHL and SNHL, the treatment should also take a combined approach Always refer to ENT for medical treatment FIRST Finally, amplify the hearing loss that remains