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  1. Topic of the Lecture: Methods of examination (evaluation) of auditory and vestibular systems 1

  2. Definition  Otolaryngology is the branch of medicine that specializes in morphology, physiology and pathology of ear, nose, upper respiratory system and nearby regions. 2

  3. Term - otorhinolaryngology  Otos - ear Greek words  Rhinos - nose  Laryngos - larynx/throat  Logos -study abbreviated– ORL or LOR 3

  4. Peripheral region Sound conduction system Sound perception system 1. Outer ear; 1. The organ of Corti (or spiral organ) 2. Middle ear; 3.Peri- and endolymphal cavities; 4.Basilar membrane; * 5. Tectorial membrane. *- inner ear structures. 4

  5. Normal hearing properties: 1. Frequency Range of Human Hearing- from 16 to 20 thsd. Hz. By bone conduction human perceives ultrasound up to 224 thsd. Hz. Normal speech frequency range– 500 – 2000 Hz 2.Unequal sensitivity to various frequencies. 3. Ototopics - capacity of localizing the source of a sound. 5

  6. The human auditory system is sensitive to sounds in terms of: - frequency (Hz); - magnitude(Db). 130 Db – highest intensity sound human is able to perceive. 30 Db – low intensity sound. 60 Db –lector’s speech. Absence of tympanic membrane and ear ossicles – hearing loss on 25-30 Db. Auditory discomfort - 80-100 Db. Rock music: - 106-110 Db in the middle of a hall; - 120 Db near stage. 6

  7. Auditory system according to Pavlov I.P. is divided as follows: 1. Peripheral region. 2. Transmitting pathway (Central auditory system). 3. Cortical region (primary auditory cortex). 7

  8. Anatomical structures of neuronal processing : Spiral ganglion- І neuron Medulla oblongata (nucleus ventralis, nucleus dorsalis) - ІІ neuron; partial decussating Superior olivary complex- ІІІ neuron Inferior colliculi, Medial Geniculate Nucleus- ІV neuron Temporal lobe (superior temporal gyrus) 8

  9. Bone conduction 1 . Inertial type (low-pitched sounds). 2. Compressional type (high-pitched sounds). 9

  10. Hearing Testing І group – Speech test. ІІ group- tuning fork tests.  Schwabach test.  Rinne test.  Weber test.  Bing test.  Federici test.  Gelle test. ІІІ group –electrophysiological or electroacoustic tests. • Subjective methods • Objective methods VІ group – using conditioned and unconditioned reflexes: • Unconditioned – auropalpebral and auropupillary reflexes • Conditioned - Conditioned Play Audiometry. 10

  11. ІІІ group – electrophysiological or electroacoustic tests. Subjective methods - Pure tone threshold audiometry; - above-threshold audiometry • Si-Si test - small increment sensitivity index test. • differential threshold test (Lüscher-Test). - Speech audiometry; - Sesitivity to ultrasound; - Hearing testing in wide frequency range. 11

  12. ІІІ group – electrophysiological or electroacoustic methods Objective methods - Registration of brainstem and cortical response to sound (computer audiometry/auditory brainstem response (ABR)к????????а? а??и?????и?); - Electrocochleography (ECochG); - Immittance Audiometry; - Evoked Otoacoustic Emissions. 12

  13. Audiometry Normal 13

  14. Audiometry Conductive hearing loss 14

  15. Audiometry Perceptive hearing loss 15

  16. Audiometry Combined hearing loss 16

  17. Immittance Audiometry  Tympanometry  Acoustic reflex thresholds  Acoustic Reflex Decay  Determination of auditory tube passage capability (function) with perforated and non-perforated tympanic membrane 17

  18. Immittance Audiometry – objective hearing test method Tympanometry – 6 tympanogram types (Jerger, 1970) type С (disfunction of auditory tube) type Аs (otosclerosis) type a (normal) type В (secretory otitis media, perforation of tympanic membrane) type Аd (ossicle chain disfunction) type D (adhesive otitis) 18

  19. Methods of examination of vestibular system (vestibulometry) 19

  20. Functions of vestibular system the semicircular canal system Otolithic organs • linear acceleration (on horizontal and vertical plane)  Angular acceleration • gravity 20

  21. Aim of vestibulometry Determination of central and peripheral vestibular syndromes Determination of hypo- or hyperreflexia of labyrinth 21

  22. Group of tests Spontaneous vestibular disfunctions 1) Experimental tests (tests with provocative measures ) 2) 22

  23. Spontaneous Vestibular Disfunctions 1. Dizziness. 2. Spontaneous past-pointing tests (outstretched hands test, pointing test, Fukuda's vertical writing test– number 30, normally deviation no more then 100). 3. Balance system evaluation (Romberg pose; ?ефа?ография (Kephalography?) – 60 dots in 60 seconds, Stabilography – evaluation of body's center of gravity, walk test). 4.Evaluation of nystagmus reaction: 1) Spontaneous nystagmus; 2) Positional nystagmus; 3) Optokinetic nystagmus; 4) Pressure nystagmus. 23

  24. El Elec ectr tronistagmograp onistagmography hy  Registration of potential difference between retina and iris tunic eyeball moving 24

  25. Experimental tests  Caloric stimulation  Rotation tests 25

  26. Ca Calo lori ric c te test st 26

  27. Ca Calo lori ric c te test st 27

  28. Rotation tests 28

  29. Po Post sturography urography 29

  30. Vestibulometry in professional selection  Otolithic reaction (off vertical axis testing).  Multiple repetition of OR (10 tests on right side and as many on the left with 2-3 min. pause)  Coriolis Acceleration Tolerance test (test of continuous accumulation of coriolis acceleration in modification of Markarian S.S.) 30

  31. Otolithic reaction (off vertical axis testing) 31

  32. Vestibulometry in professional selection Otolithic reaction (off vertical axis testing)(Voyachek V.G.) vegetative reactions 0 – reactions are absent somatic reactions 0 – reactions are absent 1 – slight deviations of the body 2 –strong deviations of the body 3 – fall out 1 –(subjective feeling of ) nausea 2 –paleness or redness of face, changes in heart and breath rate 3 – nausea and vomit (subject (patient) can not hold himself in the chair) 32

  33. Accumulation test ( 4 support PL swing) 33

  34. Vestibulometry in professional (occupational/career) selection Khilov K.L. (provocative factors/irritants) cummulation test  0 degree- after 15 minutes of swinging vegetative reactions are absent;  І degree- after 15 minutes of swinging nausea and vomit occurred;  ІІ degree- after 5-15 minutes of swinging nausea and vomit occurred;  ІІІ degree- in first 5 minutes of swinging nausea and vomit occurred. 34

  35. Coriolis Acceleration Tolerance Coriolis Acceleration arises as a result of motion of a particle relative to a rotating system (overlaying of either perpendicular forces) 35