核医学-呼吸系统

Respiratorysystem呼吸系统临床医学八年制核医学教学课件1RightupperlobeApicalsegment(1)Posteriorsegment(2)Anteriorsegment(3)RightmiddlelobeLateralsegment(4)Medialsegment(5)RightlowerlobeSuperiorsegment(6)Anteriorbasalsegment(7)lateralbasalsegment(8)posteriorbasalsegment(9)medialbasalsegment(10)Leftupperlobe(superiordivision)Apico-posteriorsegment(11,12)Anteriorsegment(13)Leftupperlobe(lingulardivision)Superiorsegment(14)Inferiorsegment(15)

LeftlowerlobeSuperiorsegment(16)Posteriorbasalsegment(17)Lateralbasalsegment(18)Antero-medialbasalsegment(19)2LungperfusionimagingPrincipleImageparticlesΦ9～60µminjectedI.V.trappedin

capillary

（8

m）、

precapillaryarterioles（35

m）

theamountofparticlesisproportionaltothelocalbloodperfusion3LungperfusionimagingSafety

*Theinjectedradioactiveparticleswere20~70million,andonly0.1%ofthepulmonaryvesselswereblocked

*

Theeffectivehalf-life2~6h,decomposedbymacrophages

*Theamountoftheinjectedproteinwasonly0.1to1%oftheminimumtoxicdose

4LungperfusionimagingIndications⑴Pulmonaryembolus(PE)⑵Pre-operativeevaluationofregionalpulmonaryfunction；⑶EvaluationofARDSandCOPD⑷Pulmonaryarterialhypertension⑸Righttoleftshuntsininheritedheartdisease⑹Suspectaortitisinvolvedpulmonaryvascular5LungperfusionimagingImagingagents

99mTclabelledmacro-aggregatedalbumin(MAA)或humanalbuminmicrospheres(HAM)99mTc-MAA99mTc-HAM6Multipositionlungperfusionimaging7ANTPOST89Tomographicimages10LungventilationimagingPrinciple

Ventilationimaging

RadioactivegasdiffusenessAerosolinhaleimaging

asuspensionofliquiddropletsinairwithparticlesizesinthemicronrangeorsmaller.Innuclearimagingaerosolsareusedinradionuclidelungimaging,wherethepatientisgivensmalldropletsofliquidcontainingtechnetium-99mDTPAtoinhale.Theaerosolparticlescanreachthealveolibecauseoftheirsmallsizeandaredepositedthere,thusactingasaventilationmarker.11LungventilationimagingIndicationsDifferentiateddiagnosisofPEorCOPDSolidpulmonarydiseaseV/QCOPD12LungventilationimagingImagingagents

●

Xe-133

●

Aerosol

99mTc-DTPA99mTc-HAS

●

Technegas1314Aerosol

15Ventilation/Perfusionscintigraphy（V/Qscan）一、肺通气灌注显像的特点

●核素显像是功能诊断

●肺灌注显像(Q):反映肺栓塞患者局部血流分布、灌注缺损部位、大小以及血液动力学意义

●肺通气显像(V):局部通气功能,损害的部位与程度,V/QImaging是否匹配16Clinicalapplications一、PulmonaryEmbolism(PE)是内源性或外源性栓子堵塞肺动脉及其分支，引起肺循环和呼吸功能障碍的临床和病理生理综合征早期诊断准确率低，25%-45%；误诊及漏诊率高，约80％未行治疗的PE患者死亡率可达30%，而经抗凝或其他治疗后，其死亡率可降至3%

10%最常见的类型是pulmonarythromboembolism(PTE)栓塞性静脉炎(thrombophlebitis)和深静脉栓塞(deepveinthrombosis,DVT)是造成PE的最直接因素171.

ClinicalmanifestationofPE通常是非特异性的，常见症状和体征有呼吸急促(tachypnea)、呼吸困难(dyspnea)、胸膜疼痛(pleuriticchestpain)和咳嗽(cough)等严重程度主要与以下两个因素有关：肺动脉栓塞程度和范围；是否有肺梗死(pulmonaryinfarction)或肺出血(pulmonaryhemorrhage)典型临床表现包括呼吸困难、胸痛和咳血，三者同时存在仅占20%182.

AccessoryexaminationofPED-二聚体(D-dimer)：对确诊PE帮助不大。对于非高危或临床低中度可能性，阴性可以排除PE，无需影像学检查；对于临床高度可能性，无需检测D-dimer，直接进一步检查。X线胸片：早期、基本的检查方法；特异性低、敏感性低；对于疑诊PE，主要作用是除外与PE临床表现相类似疾病。193.V/QscandiagnosticterminologyV/Qmismatch：灌注显像有异常改变，肺通气和/或X胸片的无异常变化；灌注显像稀疏或缺损区大于肺通气和/或X胸片CorrespondingV/Qdefects：灌注显像有异常改变，与肺通气和/或X胸片的改变一致Segmentalperfusiondefect(SPD)：pleuralbasedwedgeshapedSizeofdefect：large≧75%

moderate=25~75%

small＜25%SegmentalequivalentProbability：normal,low,intermediate,high20PE的V/Q示意图Q-defectV-normal214.DiagnosticcriteriaHighProbability>=2Largesegmentalperfusiondefects(SPD)1LargeSPDand>=2ModerateSPD.>=4ModerateSPDIntermediateProbability1Moderateto<2LargeSPDCorrespondingV/QdefectandCXRopacityinlowerlungSinglemoderatelymatchedV/Qdefect.CorrespondingV/QdefectandsmallPleuralEffusionLowProbabilityMultipleMatchingV/Qdefects.CorrespondingV/QdefectsandCXRparenchymalopacityinupperormiddlelungzone.CorrespondingV/QdefectsandlargePleuralEffusion.>3SmallSPD.VeryLowProbability<=3SmallSPD.NormalNoperfusiondefectsandperfusionoutlinestheshapeofthelungseenonCXR

ModifiedPIOPEDCriteria2223Morethan2lobeperfdefect,butventilationimagingarenormal.2425PrelytictherapyPostlytictherapy5.EvaluationofPEaftertreatment26PrelytictherapyPostlytictherapy276、比较影像学：⑴PAA金标准，最终诊断依据有创性、高危性主要适应症：无创检查结果不明确时使用诊断急性PE时有两种表现：①肺动脉中血管造影剂的突然中断，表明该处有血栓将肺动脉完全阻塞；②肺动脉内显示血栓轮廓，说明该处血栓对肺动脉造成部分阻塞，血管造影剂通过血栓缝隙流向远端28比较影像学：⑵CT可直接观察到栓子，以及血管形态和外周变化，亦可显示肺及肺外的其它胸部疾病，已成为一线检查手段对肺段以上诊断有重要价值，对发生在亚段的诊断不可靠，应结合核素影像下结论可发现被V/Q显像所漏诊的肺动脉部分栓塞性PE；V/Q显像的阴性预测值却明显高于CTCTPA对中央型PTE的诊断有优势；肺V/Q显像对周围型PTE的诊断有优势29比较影像学：⑶US也能发现肺血管内较大血栓，尤其完全栓塞性血栓无辐射，过敏少，对肾功能影响小，三维图像在段和亚段栓子显示受限不是一线检查手段⑷MR床旁超声心动图是高危疑诊肺栓塞最为有效的首选检查；是高危患者最快捷的床旁评价疗效的手段超声心动图检查不推荐作为非高危疑诊肺栓塞患者诊断策略的一部分加