简介:Endoscopicultrasonography-guidedfine-needleaspiration(EUS-FNA)hasbeenappliedtopancreaticobiliarylesionssincethe1990sandisinwidespreadusethroughouttheworldtoday.Weusedthismethodtoconfirmthepathologicalevidenceofthepancreaticobiliarylesionsandtoperformsuitabletherapies.ComplicationsofEUS-FNAarequiterare,butsomeofthemaresevere.OperatorsshouldmasterconventionalEUSobservationandexperienceaminimumof20-30casesofsupervisedEUS-FNAonnon-pancreaticandpancreaticlesionsbeforeattemptingsoloEUSFNA.StudiesconductedonpancreaticobiliaryEUSFNAhavefocusedonselectionofsuitableinstruments(e.g.,needleselection)andsamplingtechniques(e.g.,fanningmethod,suctionlevel,withorwithoutastylet,optimumnumberofpasses).Today,thediagnosticabilityofEUS-FNAisstillimproving;thedetectionofpancreaticcancer(PC)currentlyhasasensitivityof90%-95%andspecificityof95%-100%.InadditiontoPC,avarietyofrarepancreatictumorscanbediscriminatedbyconductingimmunohistochemistryontheFNAmaterials.Aflexible,largecaliberneedlehasbeenusedtoobtainalargepieceoftissue,whichcanprovidesufficienthistologicalinformationtobehelpfulinclassifyingbenignpancreaticlesions.EUSFNAcansupplyhighdiagnosticyieldsevenforbiliarylesionsorperi-pancreaticobiliarylymphnodes.ThisreviewfocusesontheclinicalaspectsofEUS-FNAinthepancreaticobiliaryfield,withtheaimofprovidinginformationthatcanenablemoreaccurateandefficientdiagnosis.
简介:摘要Endoscopic ultrasound (EUS) has both diagnostic and therapeutic clinical applications. This review article focuses on recent advances in two commonly performed procedures: EUS-guided tissue acquisition and EUS-guided drainage. There is a shift from acquiring aspirates for cytology to obtaining tissue cores for histological diagnoses and molecular analyses. There is growing interest and research about artificial intelligence in EUS. Artificial intelligence may potentially be useful to guide clinical decision making if biopsy results are non-diagnostic. The range of EUS-guided drainage procedures has expanded. EUS-guided drainage of walled-off pancreatic fluid collections is an accepted first line treatment option. EUS-guided palliative drainage of malignant biliary obstruction after unsuccessful endoscopic retrograde cholangiopancreatography (ERCP) is now an accepted alternative to percutaneous transhepatic biliary drainage. EUS-guided gallbladder drainage for management of acute cholecystitis is now a preferred option over percutaneous cholecystostomy for non-surgical candidates. Other EUS-created gastrointestinal anastomoses such as EUS-guided gastroenterostomy in the context of gastric outlet obstruction, and EUS-directed transgastric ERCP for Roux-en-Y gastric bypass are now technically feasible, but further prospective randomized studies are needed to establish the actual clinical impact.
简介:Objective: ToinvestigatethevalueoftranscranialDoppler(TCD)ultrasonographyinevaluatingtheoutcomeofseveretraumaticbraininjuryandtocorrelatetheTCDvalueswithintracranialpressure(ICP)andcerebralperfusionpressure(CPP)monitoring. Methods: AprospectivestudywasconductedtoevaluatethecontributionofTCDultrasonographytoneurologicaloutcomeinaseriesof96severetraumaticbraininjurypatients.ThequantitativevariablesofTCDultrasonographyincludedthemeanbloodflowvelocityofthemiddlecerebralartery(MCA)andpulsatilityindexwithinthefirst24hoursofadmission.TheICPandCPPvalueswerealsorecorded.Outcomein6monthspostinjurywasevaluatedusingtheGlasgowOutcomeScale(GOS4-5wasconsideredas“good”andGOS1-3as“poor”). Results: ThemeanbloodflowvelocityoftheMCAwaslargerthan40cm/sin30(51%)patientswithgoodoutcomewhereasitwaslessthan40cm/sin27(73%)patientswithpooroutcome(P<0.025).ThemeanPIincasesofgoodoutcome(34patients,57%)waslowerthan1.5whereasinpooroutcome(30patients,83%)washigherthan1.5(P<0.001).ThecorrelationsofICPandCPPtopulsatilityindexwerestatisticallysignificant(P<0.01). Conclusions: TCDultrasonographyisvalidinpredictingthepatientsoutcomeof6monthsandcorrelatessignificantlywithICPandCPPvalueswhenitisperformedinthefirst24hoursofseveretraumaticbraininjury.
简介:TherevisedAtlantaclassificationofacutepancreatitiswasadoptedbyinternationalconsensus,andisbasedonactuallocalandsystemicdeterminantsofdiseaseseverity.Thelocaldeterminantispancreaticnecrosis(sterileorinfected),andthesystemicdeterminantisorganfailure.Localcomplicationsofpancreatitiscanincludeacuteperi-pancreaticfluidcollection,acutenecroticcollection,pseudocystformation,andwalledoffnecrosis.Interventionalendoscopicultrasound(EUS)hasbeenincreasingutilizedinmanagingtheselocalcomplications.AfterperformingaPubMedsearch,theauthorsmanuallyappliedpre-definedinclusioncriteriaorafiltertoidentifypublicationsrelevanttoEUSandpancreaticcollections(PFCs).Theauthorsthenreviewedtheutility,efficacy,andrisksassociatedwithusingtherapeuticEUSandinvolvedEUSdevicesintreatingPFCs.Duetothedevelopmentandregulatoryapprovalofimprovedandnovelendoscopicdevicesspecificallydesignedfortransmuraldrainageoffluidandnecroticdebris(accessandpatencydevices),theauthorspredictcontinuingevolutioninthemanagementofPFCs.WebelievethatEUSwillbecomeanindispensablepartofproceduresusedtodiagnosePFCsandperformimage-guidedinterventions.AfterdrainingaPFC,theamountoftissuenecrosisisthemostimportantpredictorofasuccessfuloutcome.Hence,itseemslogicaltoclassifythesecollectionsbasedontheirpercentageofnecroticcomponentordebrispresentwhenviewedbyimagingmethodsorEUS.Finally,theauthorsproposeanalgorithmformanagingfluidcollectionsbasedontheirsize,location,associatedsymptoms,internalechogenicpatterns,andcontent.
简介:Pancreaticcysticlesions(PCLs)areincreasinglybeingidentifiedbecauseofthewidespreaduseofhighresolutionabdominalimaging.Thesecystsencompassaspectrumfrommalignantdiseasetobenignlesions,andtherefore,accuratediagnosisiscrucialtodeterminethebestmanagementstrategy,eithersurgicalresectionorsurveillance.However,thecurrentstandardofdiagnosisisnotaccurateenoughduetolimitationsofimagingandtissuesamplingtechniques,whichentailtheriskofunnecessaryburdensomesurgeryforbenignlesionsormissedopportunitiesofprophylacticsurgeryforpotentiallymalignantPCLs.Inthelastdecade,endoscopicinnovationsbasedonendoscopicultrasonography(EUS)imaginghaveemerged,aimingtoovercomethepresentlimitations.ThesenewEUS-basedtechnologiesarecontrastharmonicEUS,needle-basedconfocalendomicroscopy,through-the-needlecystoscopyandthrough-theneedleintracysticbiopsy.Here,wepresentacomprehensiveandcriticalreviewoftheseemergingendoscopictoolsforthediagnosisofPCLs,withaspecialemphasisonfeasibility,safetyanddiagnosticperformance.
简介:AIM:Toevaluatetheclinicalusefulnessofendoscopicultrasonography(EUS)forthediagnosisoftheinvasiondepthofulcerativecolitis-associatedtumors.METHODS:Thestudygroupcomprised13patientswith16ulcerativecolitis(UC)-associatedtumorsforwhichthedepthofinvasionwaspreoperativelyestimatedbyEUS.Thelesionswerethenresectedendoscopicallyorbysurgicalcolectomyandwereexaminedhistopathologically.Themeanageofthesubjectswas48.2±17.1years,andthemeandurationofUCwas15.8±8.3years.Twolesionsweretreatedbyendoscopicresectionandtheother14lesionsbysurgicalcolectomy.ThedepthofinvasionofUCassociatedtumorswasestimatedbyEUSusinganultrasonicprobeandwasevaluatedonthebasisofthedeepestlayerwithnarrowingorruptureofthecolonicwall.RESULTS:ThediagnosisofUC-associatedtumorsbyEUSwascarcinomafor13lesionsanddysplasiafor3lesions.Theinvasiondepthofthecarcinomaswasintramucosalfor8lesions,submucosalfor2,themuscularispropriafor2,andsubserosalfor1.Eleven(69%)ofthe16lesionsaroseintherectum.Themacroscopicappearancewasthelaterallyspreadingtumor-non-granulartypefor4lesions,sessiletypefor4,laterallyspreadingtumor-granulartypefor3,semipedunculatedtype(Isp)for2,type1for2,andtype3for1.ThedepthofinvasionwascorrectlyestimatedbyEUSfor15lesions(94%)butwasmisdiagnosedasintramucosalfor1carcinomawithhigh-gradesubmucosalinvasion.The2lesionstreatedbyendoscopicresectionwereintramucosalcarcinomaanddysplasia,andbothwerediagnosedasintramucosallesionsbyEUS.CONCLUSION:EUSprovidesagoodestimationoftheinvasiondepthofUC-associatedtumorsandmaythusfacilitatetheselectionoftreatment.
简介:Commonpracticedictatestheperformanceofpercutaneouscoronaryinterventionunderconventionalangiographicguidance.Withstudiessuggestingthehighincidenceofintraobservervariability,especiallyinangiographicborderlinelesions,newmodalitiessuchasintravascularultrasound(IVUS)guidanceduringpercutaneouscoronaryinterventionhavesurfaced.MultiplestudieshaveshownimprovedoutcomeswithIVUSguidance,mainlydrivenbyadecreaseinischemia-driventargetlesionrevascularization.Inthepasttwodecades,amultitudeofstudieshaveinvestigatedtheusesandclinicaloutcomesassociatedwiththistechnology.Inthisreview,wehighlighttheutility,advantages,economicimplications,andclinicaloutcomesofIVUSguidanceoverstandardangiographicguidance,withemphasisondataastheypertaintoIVUS-guidedstentimplantation.
简介:有人的脸的图象在成像领域包括必要部分。在面部部分的吸藏或损坏将带显著不快和信息损失。我们建议能修理的一个算法堵塞了或自动地损坏了面部图象,命名‘facial图象inpainting'。Inpainting是处理方法恢复失踪的图象部分的一套图象。我们在由介绍面部领域知识油漆方法扩大图象。与一个脸数据库的支持,我们的途径宣传结构的信息,即,特征点和边地图,从类似的脸到失踪的面部区域。把推断的结构的信息用作指导,在油漆算法的一幅基于模范的图象被采用从来源部分在一样的脸拷贝补丁到失踪的部分。在油漆的面部图象的这个最新建议的概念超过在美容从一个脸数据库塑造,并且由从一样的脸图象推断颜色和质地从不同图象处于成像条件避免变化的问题的由宣传的画方法传统。我们的系统生产是几乎没看见的缺点的无缝的脸。
简介:Thedispersioncharacteristicsandexcitationmechanismsoftheguidedwavesinmultilayeredplatesarestudiedinthispaper.Firstly,thedispersionequationisobtainedbythepropagatormatrixmethod.Then,thebisectiontechniqueisemployedtofindalltherootsofthedispersionequation.Thedispersioncharacteristicsoftheguidedwavesareinvestigatedandanalyzed.ForthemultilayeredplatesinwhichtheS-wavevelocityincreasesordecreasesfromtoptobottom,itisfoundthatthevelocitylimitsinhighfrequencyofthefirstandhighmodesareequaltotheRayleighwaveandS-wavevelocitiesofthelow-velocitylayer,respectively.ItisalsofoundthatthevelocitylimitsinthehighfrequencyofallmodesareequaltotheS-wavevelocityofthelow-velocitylayerfortheplatewithalow-velocitymiddlelayer.Thenormaldisplacementspectrumofallthemodesexcitedbythenormalforcesourcewithadefinitewidthonthesurfaceoftheplateisalsoinvestigated.ItisprovedthatthedominantmodeisthefirstmodewhentheS-wavevelocityincreasesfromtoptobottomlayerandthedominantmodeisdifferentindifferentfrequencyrangefortheplatewithalow-velocitymiddlelayer.
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简介:Usingultrasonicguidedwavestoassesslongbonefracturesandfracturehealinghasbecomeapromisingdiagnosticissue.Butthemultimodeoverlapoftheguidedwaveschallengesthequantitativeevaluationandclinicalapplication.Inthepreformedstudy,inordertosimplifythesignalinterpretation,thelow-frequencysinusoidialsignalswereusedtoonlyexciteS0andA0modesinfracturedlongbones.TheamplitudesofS0andA0modeswerenumericallyanalyzedwithvariationincrackwidthandfractureangle.Numericalsimulation,basedonthetwo-dimensionfinite-differencetime-domain(2D-FDTD)revealsthatbothS0andA0amplitudesdecreasewiththefracturewidening.However,theincreaseinfractureanglegraduallyenhancestheA0amplitude,whilewithrespecttotheS0mode,itsamplitudeshowsanon-monotonictrendtothevariationinfractureanglewithaturningpointaround45°.TheamplituderatiobetweenS0andA0canreflectthevariationsincrackwidthandfractureangles.ThesimulationillustratesthatultrasonicguidedS0andA0modesaresensitivetothedegreeofbothverticalandobliquefracturesinthelongcorticalbone.Thesefindingsmaybehelpfulforfracturesdiagnosisandhealingevaluationofthelongbone.
简介:Asimplifiedmodalmethodtoexplaintheresonancephenomenoninguidedmoderesonance(GMR)gratingswithasymmetriccoatingsispresented.Theresonanceobservedisduetotheinteractionoftwopropagationmodesinsidethegrating.Thereflectivityspectraandelectricfielddistributionscalculatedfromthesimplifiedmodalmethodarecomparedusingrigorouscoupled-waveanalysis(RCWA).Theinfluencesofhigh-orderevanescentmodesontheresonancepeakareanalyzed.AmatrixFabry-Perot(FP)resonanceconditionisdevelopedtoevaluatetheresonancewavelength.AnexplanationfortheresonancephenomenonobservedbasedontheFPresonancephaseconditionisalsoproposedanddemonstrated.ThesimplifiedmethodprovidesclearphysicalinsightsintoGMRgratingsthatareusefulfortheanalysisofavarietyofotherresonancegratings.
简介:Inanefforttodevelopbiomaterialstomeetguidedtissueregeneration(GTR)standardsforperiodontaltissuerecovery,ahomogeneousandtransparentchitosan(CS)/hydroxyapatite(HA)membranewithpotentialapplicationsasGTRbarrierinperiodontaltherapyhasbeenpreparedviainsitucompositing.ThemembranehasbeendesignedtohaveasmoothroughasymmetricstructurethatmeetsthedemandforGTR.ComponentandmorphologyofthemembranearecharacterizedbyXRDandSEM.ItcanbeindicatedthatHAwasinsitusynthesizeduniformlyintheCSmembrane.MechanicalexperimentsofthemembraneswithvariousHAcontentsshowthattheirtensilestrengthsareadequateforperiodontaltherapy.Biologicalpropertiesofthemembranehavebeenperformedbycelltoxicityassays,hemolysistestsandanimalexperiments.Resultsindicatethatthemembranehasgoodbiocompatibilityandinductiveeffectforcellgrowth.ThereforethismembranecanbepotentiallyappliedasGTRbarriermembraneforperiodontaltissueregeneration.
简介:Inthispapermodellingofthetranslationalmotionoftransportationrail-guidedcartwithropesuspendedpayloadisconsidered.Thelinearlymovingcart,drivenbyatravelmechanism,ismodelledasadiscretesixdegreesoffreedom(DOF)dynamicsystem.ThehoistingmechanismforloweringandliftingthepayloadisconsideredandisincludedinthedynamicmodelasoneDOFsystem.DifferentialequationsofmotionofthecartelementsarederivedusingLagrangiandynamicsandaresolvedforasetofreal-lifeconstantparametersofthecart.Atwo-sidedinteractionwasobservedbetweentheswingingpayloadandthetravelmechanism.Resultsforkinematicalandforceparametersofthesystemareobtained.Averificationoftheproposedmodelwasconducted.