1. SUDDEN HEARING LOSS

3. Anatomy of Ear

5. กลไกการได้ยินเสียง (Hearing mechanism)

6. Hearing Loss

10. Different of Conductive&Sensorineural Hearing Loss Sensory Neural Conductive 1. Site 2. Deafness because Outer or middle ear. Vibrations do not reach the inner ear or arrive there attenuated. Inner ear or cochlea and the nerve pathways to auditory centres in the brain. Vibrations are not registered by nerve cells in the inner ear because they are damaged, or have never developed.

12. Infection Chondritis Aspergillus Niger Otitis Externa Acute otitis media Chronic otitis media

13. Trauma Bullous Myringitis Granular Myringitis TM perforate Cholesteatoma

14. Tumor Glomus tympanicum Exostosis Osteoma Squamous cell carcinoma

15. Different of Conductive&Sensorineural Hearing Loss Sensory Neural Conductive 4. Amenable to treatment Medical and surgical procedures can be effective. There is not a cure for sensory neural hearing loss, however a cochlear implant may be an option for a deaf person.

16. Different of Conductive&Sensorineural Hearing Loss Sensory Neural Conductive 5. Characteristics of hearing loss Loss for low and high pitch sounds is similar. Usually a mild to moderate degree of hearing loss. Usually the loss of hearing for high pitches is greater - often much greater than for low pitch sounds. Hearing loss can range from mild to profound.

17. Different of Conductive&Sensorineural Hearing Loss Sensory Neural Conductive 6. How speech is heard Muffling in the perception of speech. Usually there is minimal distortion in the perception of the speech signal. Hearing aids sound very clear. Distortion in the perception of speech. Vowels may be heard relatively well; consonants are often distorted, if heard at all. Hearing aids sound somewhat distorted, but are necessary.

20. Otoscope

21. Tuning fork test

23. Degree of hearing loss estimated by Rinne testing Estimated conductive loss Rinne test result Mild conductive loss of 20-30 dB Negative, 256 Hz Positive, 512 and 1024 Hz Moderate conductive loss of 30-45 dB Negative, 256 and 512 Hz Positive, 1024 Hz Severe conductive loss of 45-60 dB Negative, 256, 512, 1024 Hz

25. Audiometry

26. ผลการตรวจ Audiogram Normal

27. ผลการตรวจ Audiogram Conductive Hearing Loss Sensorineural Hearing Loss