impedance audiometry part2
TRANSCRIPT
Aditya Ghosh RoyPGT2
MS ENT
IMPEDANCE AUDIOMETRY
FALLACIES OF TYMPANOMETRY TEST
MIDDLE EAR PATHOLOGY TWO TYPES
STATIC COMPLIANCE REPRESENTIVE OF THE MORE LATERAL PATHOLOGY
EAC TM MEC COCHLE
A
1.STAPEDIAL FIXATION AND COMMON COLD
-- MEP WITH LOW COMPLIANCE EXPECTED
BUT -- MEP WITH LOW COMPLIANCE
OTITIS MEDIA WITH EFFUSION
CASE 1.
STAPEDIAL FIXATION AND SCARRED / HEALED TM
NORMAL MEP WITH HIGH COMPLIANCE
BUT NORMAL MEP WITH HIGHCOMPLIANCE
OSSICULAR DISCONTINUITY
CASE 2.
THICKENED TM OT TYMPANOSCLEROTIC PATCH
NORMAL MEP WITH LOW COMPLIANCE
NORMAL MEP WITH LOW COMPLIANCE
STAPEDIAL OTOSCLEROSIS
CASE 3
SMALL PERFORATION OF TM
FLAT TYPE TYMPANOGRAM WITH NORAL VOLUME
FLAT TYPE TYMPANOGRAM WITH NORAL VOLUME
ADHESIVE OTITIS MEDIA, OTITIS MEDIA WITH EFFUSION
CASE 4.
OSSICULAR DISCONTINUITY WITH THIKENED TM
NORMAL MEP WITH LOW COMPLIANCE
NORMAL MEP WITH LOW COMPLIANCE
STAPEDIAL OTOSCLEROSIS
CASE 5
FUNCTION OF EUSTACHIAN TUBE
EUSTACHIAN TUBE FUNCTION TESTMAINTAINANCE OF EQUALITY OF AIR PRESSURE BETWEEN THE MIDDLE EAR AND AMBIENT ATMOSPHERE
DRAINAGE OF MUCUS FROM EAR TO THE NASOPHARYNX
AIR IN MIDDLE EAR CAVITY CONSTANTLY BEING ABSORBED
STEADY FALL IN MIDDLE EAR PRESSURE
CONTRACTION OF TENSOR PALATINI AND LEVATOR PALTINI MUSCLE DURING SWALLOWING
INTERMITTENT OPENING OF ET
AIR PASSING THROUGH IT INTO MEC
PRESSURE IN MEC BROUGHT BACK TO NORMAL
FOR TESTING WE SEE WHETHER
VALSALVA
SWALLOWING DECREASE MEP
INCREASE MEP
TWO TYPES OF TEST ARE AVAILABLE
WILLIAMS
TOYNBEES PERFORATED TM
INTACT TM
MEP MEASURED
WILLIAMS TESTRESTING
PRESSURESWALLOING WITH NOSE MOUTH
CLOSEDVALSALV
A
NORMAL PARTIALLY IMPAIRED
GROSSLY IMPAIRED
RESTING PRESSURE
0 mm WATER
SWALLOING WITH NOSE MOUTH CLOSED
NEGATIVE NEAGATIVE
NO CHANGE
NO CHANGE
VALSALVA POSITIVE NO CHANGE
POSITIVE NO CHANGE
NORMAL
RESTING PRESSURE 0 mm WATER
SWALLOING WITH NOSE MOUTH CLOSED
NEGATIVE
VALSALVA POSITIVE
PARTIALLY IMPAIRED
SWALLOING WITH NOSE MOUTH CLOSED
NEAGATIVE NO CHANGE
VALSALVA NO CHANGE NEAGATIVE
GROSSLY IMPAIRED
SWALLOING WITH NOSE MOUTH CLOSED
NO CHANGE
VALSALVA NO CHANGE
AUDIOMETER
ARTIFICIALLY INC OR DEC MEP
RECORD CHANGE IN PRESSURE EACH TIME PT. SWALLOWS
TEST CARRIED OUT FOR FIXED DURATION40SEC TO MAX 160 SEC
TOYNBEES TEST
MEP CHANGED EITHER TO +250 OR -250
PT. ASKED TO SWALLOW
CHANGE IN MEP EITHER DEC OR INC NOTED IN A STEP
LADDER PATTERN
MEP WHEN TUBE CLOSED
SUDDEN OPENING OF TUBE
DEC IN MEP
AGAIN PASSIVE CLOSURE OF TUBE
MEP BECOMES STEADY
AGAIN PT. ASKED TO SWALOW
CHANGE IN MEP
HENCE A STEP LADDER PATTERN GRAPH OBTAINED
STEP LADDER PATTERN GRAPH
OPENING OF TUBE
DEC IN MEPPASSIVE CLOSURE OF TUBE
MEP BECOMES STEADY
NORMAL PRESSURE NEUTRALISES BY 3 TO 4 SWALLOWS
PARTIALLY IMPAIRED
SOME PRESSURE PERSISTS EVEN AFTER MORE THAN 5 SWALLOWS
GROSSLY IMPAIRED
NOT NEUTRALISED AT ALL BY EPEATED SWALLOWING
NORMAL
PRESSURE NEUTRALISES BY 3 TO 4 SWALLOWS
PARTIALLY IMPAIRED
SOME PRESSURE PERSISTS EVEN AFTER MORE THAN 5 SWALLOWS
GROSSLY IMPAIREDNOT NEUTRALISED AT ALL BY EPEATED SWALLOWING
ACOUSTIC REFLEX TESTMIDDLE EAR CAVITY
STAPEDIUS TENSOR TYMPANI
7TH NERVE 5TH NERVE
EFFECT OF CONTRACTION OF STAPEDIUS MUSCLE MORE PRONOUNCED THAN THAT
OF TENSOR TYMPANI
ACOUSTIC REFLEX TESTED BY CONTRACTION OF STAPEDIUS MUSCLE
CONTRACTION OF TENSOR TYMPANI TESTED SEPARATELY
STIMULATION OF TRIGEMINAL NERVE AND DOING AUDIOMETRY
STARTLE TYPE REFLEXFATIGUEBLE IN NATUREUNSTABLELONG LATENCY PERIOD
DONE IN PT. WITH SEVERE DEAFNESS IN WHOM ACOUSTIC REFLEX CANT BE PERFORMED BUT MIDDLE EAR STATUS HAS TO BE KNOWN
NON ACOUSTIC REFLEX
ACOUSTIC REFLEX ARC
DIAGRAMMATIC REPRESENTATION OF ACOUSTIC REFLEX
Stimulus of 85 db of 1 sec
NORMAL EAR DEAF EAR
IPSILATERAL
CONTRALATERAL
IPSILATERAL
CONTRALATERAL
PRESENT ABSENT ABSENT ABSENT
UNILATEAL MODERATE TO SEVERE CONDUCTIVE HEARING
LOSS
NORMAL EAR
DEAF EAR
NORMAL EAR
NORMAL EAR
DEAF EAR
DEAF EAR
DEAF EAR
NORMAL EAR
DEAF EAR DEAF EAR
IPSILATERAL
CONTRALATERAL
IPSILATERAL
CONTRALATERAL
ABSENT ABSENT ABSENT ABSENT
BILATEAL MODERATE TO SEVERE CONDUCTIVE HEARING LOSS
DEAF EAR
NORMAL EAR
DEAF EAR
DEAF EAR
NORMAL DEAF EAR
IPSILATERAL
CONTRALATERAL
IPSILATERAL
CONTRALATERAL
PRESENT ABSENT ABSENT PRESENT
UNILATERAL SEVERE SNHL
NORMAL EAR
DEAF EARNORMAL EAR NORMAL
EAR
DEAF EAR
NORMAL EAR
DEAF EAR DEAF EAR
IPSILATERAL
CONTRALATERAL
IPSILATERAL
CONTRALATERAL
ABSENT ABSENT ABSENT ABSENT
BILATERAL SNHL
DEAF EAR DEAF EAR
IPSILATERAL
CONTRALATERAL
IPSILATERAL
CONTRALATERAL
PRESENT PRESENT PRESENT PRESENT
SEVERE NEURAL IN NATURE
MODERATE DEGREE AND COCHLEAR IN
NATURE
DEAF EAR
NORMAL EAR
DEAF EAR
DEAF EAR
NORMAL EAR NORMAL EAR
IPSILATERAL
CONTRALATERAL
IPSILATERAL
CONTRALATERAL
PRESENT ABSENT PRESENT ABSENT
CENTRAL LESION
CENTRAL LESION