聲導(dǎo)抗基礎(chǔ)知識(shí)演示文稿

聲導(dǎo)抗基礎(chǔ)知識(shí)演示文稿當(dāng)前第1頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)聲導(dǎo)抗基礎(chǔ)知識(shí)當(dāng)前第2頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Soundtravel聲音傳導(dǎo)當(dāng)前第3頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Gettingsoundintoadifferentmedium

聲音在不同媒介中的傳導(dǎo)Mostofthesoundenergyisreflectedwhenconfrontingaanothermedium...大部分聲能在臨界面處被反射回來(lái)…becausedifferentmediaaremoreorlesseasytobringintomotion(impedance)因?yàn)椴煌浇榈穆曌杩故遣煌漠?dāng)前第4頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Theroleofthemiddleear中耳的作用

當(dāng)前第5頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)TheOssicles聽(tīng)小骨Malleus錘骨Incus砧骨Stapes鐙骨Threesmallbonesformingachainbetweenthetympanicmembraneandtheinnerear聽(tīng)骨鏈位于鼓膜和內(nèi)耳之間，由3塊聽(tīng)小骨組成Airbornesoundwaveenergybecomesmechanicalvibration空氣傳導(dǎo)的聲波能量轉(zhuǎn)換為機(jī)械振動(dòng)Compensatesfortheair-fluidimpedancedifference補(bǔ)償氣液相不同媒介的導(dǎo)抗差當(dāng)前第6頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)TheMiddleearanatomy中耳解剖AirAirAirpressuremustbenearequalonbothsidesoftheeardruminordertooptimisemobilityofthewholesystem應(yīng)使鼓膜兩側(cè)氣壓接近，從而保證中耳傳聲系統(tǒng)的最佳活動(dòng)性TheEustachiantube(ET)ventilatesthemiddleearandallowspressureequalisation咽鼓管是中耳的通氣管道，可保證中耳氣壓平衡TheETopenswhenswallowingoryawning吞咽和打哈欠時(shí)咽鼓管開(kāi)放Innerearfluids內(nèi)淋巴當(dāng)前第7頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Gettingsoundintoadifferentmedium

聲音在不同媒介中的傳導(dǎo)The“stiletto”principle:圓錐效應(yīng)Forceiscollectedoveralargerareaandfocusedonasmallerarea(B)作用力在錐底收集后聚焦到錐尖當(dāng)前第8頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Howdowetestthemiddleear?

如何檢測(cè)中耳功能當(dāng)前第9頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)中耳測(cè)試精密的中耳系統(tǒng)高精度的測(cè)試高質(zhì)量控制系統(tǒng)當(dāng)前第10頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Partoftheprobetoneisreflected,andsomeisadmittedintothemiddleear一部分探測(cè)音被反射回來(lái)，另一部分則進(jìn)入中耳Theadmittanceiscontinuouslymeasuredbyamicrophone聲導(dǎo)納通過(guò)麥克風(fēng)持續(xù)測(cè)量計(jì)算出來(lái)Admittance-lettingthesoundwavein

聲導(dǎo)納－將聲波導(dǎo)入當(dāng)前第11頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)鼓室圖中耳–勁度TPP(=MEP?)AdmittancePressure當(dāng)前第12頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Tympanometry鼓室聲導(dǎo)抗Admittance-200daPa200daPa0EarcanalpressureAdmittance聲導(dǎo)納-200daPa200daPa0Earcanalpressure外耳道壓強(qiáng)1&3:Pressurestiffensthetympanicmembranesotheprobetonebouncesback,andthesoundlevelinthemiddleeardecreases1和3：大壓強(qiáng)使鼓膜僵硬從而探測(cè)音多被反彈回來(lái)，進(jìn)入中耳的聲能減少2:Whenpressureisequalonbothsides,thesoundlevelinthemiddleearisatmaximum2：鼓膜兩側(cè)壓力相等時(shí)傳入中耳的聲能最大

123當(dāng)前第13頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)TheTympanogramcurve,ECVandTPP

鼓室導(dǎo)抗圖形，等效外耳道容積和峰壓點(diǎn)TheTPPapproximatesthemiddleearpressure峰壓點(diǎn)近似于鼓膜內(nèi)側(cè)的中耳壓力ECVTotalAdmittanceoftheearcanalandthemiddleear外耳道和中耳的聲導(dǎo)納總值TPPPressuresweepThe226Hzadmittanceoftheairintheearcanalisdirectlyproportionaltothevolumeofthatair.ThatgivesustheEquivalentEarCanalVolume,ECV以226Hz為探測(cè)音，測(cè)試探頭與鼓膜之間的空氣導(dǎo)納值為外耳道容積，即等效外耳道容積當(dāng)前第14頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)ECVTotalAdmittanceSATPPSATPPTheTympanogramcurveandbaselinecompensation鼓室導(dǎo)抗圖形和基線補(bǔ)償SubtractionoftheECVcontributiongivesusabaselinecompensatedtympanogram去除外耳道容積成分后的鼓室圖稱為基線補(bǔ)償鼓室導(dǎo)抗圖PeakadmittancebecomesStaticAdmittance,SA該圖峰值處的聲導(dǎo)納稱為靜態(tài)聲導(dǎo)納(SA)TheSAistheadmittanceofthemiddleearalone.Nowwecanusethenormativedata!SA等于中耳的聲導(dǎo)納值當(dāng)前第15頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)-2002000TypeAd:OssiculardiscontinuityoragerelatedhypermobilityAd型：聽(tīng)骨鏈中斷或鼓膜松弛-2002000TypeA:NormalA型：正常-2002000TypeB:“Flat”-EffusionorperforatedeardrumdependingonECVvalueB型：平坦型。鼓室積液或鼓膜穿孔，根據(jù)ECV值區(qū)分-2002000TypeAs:PossibleeffusionorotosclerosisAs型：鼓室積液可能或耳硬化癥-2002000TypeC:AbnormalpressureC型：負(fù)壓型TheTympanogramcurveclassification,Type鼓室導(dǎo)抗圖形分類當(dāng)前第16頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)SATWSA/2PressureAdmittanceTheTympanogramcurveandTympanometricWidth

鼓室導(dǎo)抗圖形與鼓室圖寬度（TW）TympanometricWidthquantifythesteepnessofthetympanogramTW決定鼓室導(dǎo)抗圖的坡度Normativedataexistfordifferentagegroups不同年齡組標(biāo)準(zhǔn)化值不同TWandSAarethecriteriausedintheASHAtympanometricscreeningprotocol美國(guó)社會(huì)衛(wèi)生學(xué)會(huì)的鼓室聲導(dǎo)抗篩查方案把TW和SA作為診斷指標(biāo)當(dāng)前第17頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)226Hz:Differentconfigurationsoftympanometricresults

226Hz鼓室聲導(dǎo)抗測(cè)試結(jié)果與疾病的關(guān)系Tympanometryisaninvaluablediagnostictoolwhencombinedwithotheraudiologicaltests鼓室聲導(dǎo)抗與其它聽(tīng)力學(xué)測(cè)試結(jié)合是不可替代的診斷工具疾病早期中耳積液中耳積液聽(tīng)骨鏈中斷鼓膜病變耳硬化癥錘骨固定咽鼓管阻塞鼓膜置管鼓膜穿孔耵聹栓塞、探頭叩堵塞當(dāng)前第18頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Thetwomiddleearmuscles中耳肌121:Tensormuscle鼓膜張肌2:StapediusMuscle鐙骨肌Themusclesarebelievedtostabilisethemechanicalsystemandprotectthecochleafromexcessivelowfrequencyvibration中耳肌可穩(wěn)定中耳機(jī)械系統(tǒng)，并保護(hù)耳蝸免受低頻強(qiáng)聲損傷當(dāng)前第19頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)TheAcousticReflex聲反射Loudsoundsmakethestapediusmusclecontract.Thismakesthemiddleearsystemstiffer...強(qiáng)聲刺激可使鐙骨肌收縮，從而增加中耳傳聲系統(tǒng)的勁度…andlesslowfrequencysoundcangetthroughthemiddleear因而進(jìn)入中耳的低頻聲波減少當(dāng)前第20頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Stapediusmusclecontrolledbyfacialnerve(CNVII)鐙骨肌由第七對(duì)顱神經(jīng)－面神經(jīng)支配Networkinbrainstemconsistsofipsilateralandcontralateralpaths腦干層面由同側(cè)和對(duì)側(cè)神經(jīng)通路組成Reflexactivatedonbothears,evenwhenstimulationonlyoccursinoneear一側(cè)耳受到刺激時(shí)，雙側(cè)鐙骨肌都會(huì)收縮Comparisonofipsilateralvs.contralateralacousticreflexeshelpstodeterminesiteoflesion對(duì)比同側(cè)和對(duì)側(cè)聲反射有助于判斷病變部位TheMiddleear-Immittancetests中耳聲導(dǎo)納測(cè)試Acousticreflexthreshold聲反射閾當(dāng)前第21頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)聲反射AdmittanceTimeDeflection0.02蹬骨肌當(dāng)前第22頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)0.000.0280dBHL0.000.0285dBHL0.000.0295dBHL0.000.0290dBHLDeflectioncriterion聲導(dǎo)納偏移標(biāo)準(zhǔn)Itisusefultostudythegrowthwithintensitytoconfirmareflexthreshold繼續(xù)增加聲強(qiáng)觀察偏移變化有助于進(jìn)一步明確聲反射閾?!AcousticReflexThresholds聲反射閾Loudstimuliarepresented,whilsttheadmittanceismeasured強(qiáng)聲刺激出現(xiàn)時(shí)，可測(cè)試出聲導(dǎo)納值的變化當(dāng)前第23頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)聲反射測(cè)試–高精度的挑戰(zhàn)鼓膜處壓力為T(mén)PP值時(shí)中耳蹬骨肌反射狀況最佳正確的聲反射是刺激音引起導(dǎo)納在TPP處的變化耳道或中耳壓力的改變導(dǎo)致錯(cuò)誤的聲反射對(duì)于鼓膜活動(dòng)度過(guò)大可進(jìn)行TPP補(bǔ)償當(dāng)前第24頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Threshold+10dB,10secondsstimulustime聲反射閾上10dB給聲，刺激時(shí)程10s0510secondsAdmittancechangeHalf-LifeTime(HLT),thetimeafterstimulusonsetwhentheadmittancedeflectionhasdecreasedby50%.半衰期是指聲反射振幅減少50％的時(shí)程Ahalf-lifetimevalue<5secondsisindicativeoftumour半衰期小于5秒提示蝸后病變，常見(jiàn)的疾病是聽(tīng)神經(jīng)瘤Noreflexdecaypresent陰性AdmittancechangeMax50%ofMaxHLT0510secondsReflexdecaypresent!陽(yáng)性AcousticReflexDecay聲反射衰減當(dāng)前第25頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)Thereflexshouldbeactivatedinbothearsevenifstimulatedinonlyoneear單耳刺激聲可激活雙耳聲反射Theuppernormalintensitylimitforreflexthresholdsinadultsis95-100dBHL正常成人聲反射閾上限是95－100dBHLReflexthresholdscannotbedeterminedifthereisaproblemwiththemiddleear

中耳疾病時(shí)不能測(cè)出聲反射閾BroadBandNoiseprovokesareflexatabout10-15dBlowerthanpuretonestimuli寬帶噪聲聲反射閾較純音刺激聲低10－15dBDeterminestypeofhearinglosswhencomparedwiththeaudiogram聲反射閾與聽(tīng)力圖比較可幫助判斷耳聾類型Decayswithneuralfatigue(typically8thnervetumour)

衰減提示聽(tīng)神經(jīng)疲勞，是聽(tīng)神經(jīng)腫瘤的典型表現(xiàn)AcousticReflexfeatures聲反射特征當(dāng)前第26頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)DifferentconfigurationsofAcousticReflexresults聲反射結(jié)果與疾病的關(guān)系Usingthiskindoftablemakesreflexinterpretationeasier使用該表格有助于判斷聲反射的臨床意義病變部位/患耳中耳/右中耳/左耳蝸/右耳蝸/左聽(tīng)神經(jīng)/右聽(tīng)神經(jīng)/左面神經(jīng)/右面神經(jīng)/左腦干/右腦干/左腦干/中線當(dāng)前第27頁(yè)\共有32頁(yè)\編于星期六\23點(diǎn)226Hzprobetone:Normaltympanograminabnormalear!226Hz探測(cè)音：異常中耳顯示正常鼓室導(dǎo)抗圖Tympanometryininfantsyoungerthan4-7months4－7個(gè)月以下嬰兒的鼓室聲導(dǎo)抗226HzprobetoneTheinfantouterandmiddleearsarestilldeveloping,anddonotvibratewithsoundthesamewayadultearsdo.嬰兒外耳和中耳正處于發(fā)育期，與成人的聲波振動(dòng)方式不