视神经鞘直径(ONSD)与颅内压(ICP)重症医学科解剖学基础解剖学基础Pulillary aperature 瞳孔Iris 虹膜Cornea 角膜Ciliary body 睫状体Lens 晶状体Vitreous body 玻璃体Retina 视网膜Choroid 脉络膜Sclera 巩膜眼部结构及超声图像眼球及眶周结构 视路MRI图像 视神经：眼内部眶部（ONSD段）管内部颅内部CriticalCare2008,12:R114ONSD视神经ONSD临界值5.82mmICP20mmHg共纳入231例敏感性0.90（95%CI0.80-0.95）特异性0.85（95%CI0.73-0.93）IntensiveCareMed(2011)37:10591068ConclusionsSonographicmeasurementofONSDmaybeapotentiallyusefultechniqueforassessingIHinabinarymode(present/absent)wheninvasive/monitoringmethodsarenotdesirableoravailable.视神经鞘直径可准确评估颅内压增高？ConclusionThisstudysuggeststhatONSDassessmentthroughouttheacutephasemaynotbeareliablemethodtomonitorICP. ONSDexpansioncanpersistevenafterICPcontrol,andthismaybethereasonforONSDexpansionsseeninourstudyevenwithnormalICPs.Furtherlargersizestudiesareneededtoconfirmthesefindings.影响因素1、体位EffectsofPronePositionandPositiveEnd-ExpiratoryPressureonNoninvasiveEstimatorsofICP:APilotStudy.Results:ThemeanvaluesofONSD,ICPFVd,andICPPIsignificantlyincreasedafterchangefromsupinetoproneposition.Receiveroperatingcharacteristicanalysesdemonstratedthat,amongthenoninvasivemethods,themeanONSDmeasurehadthegreatestareaunderthecurvesignifyingitisthemosteffectiveindistinguishingahypotheticalchangeinICPbetweensupineandpronepositioning(0.86+/-0.0340.79to0.92).Acutoffof0.43cmwasfoundtobeabestseparatorofONSDvaluebetweensupineandpronewithaspecificityof75.0andasensitivityof86.7.Conclusions:NoninvasiveICPestimationmaybeusefulinpatientsatriskofdevelopingintracranialhypertensionwhorequirepronepositioning.JournalofNeurosurgicalAnesthesiology.18March20162肥胖、气腹Therewere62subjects,28females(45.2%)and34males(54.8%),withameanageof44.2210.44years(range2366).Forty-eightpercentofpatientswerenon-obese,and52%ofpatientswereobese.Themeanbodymassindexwas30.707.61kg/m2(range20.059.5).ThemeanONSDofnon-obeseandobesepatientswas4.7 and 5.5 mm atbaseline(p=0.01),5.4 and 6.2 mm at15min(p=0.01),5.8 and 6.6 mm at30min(p=0.01),and5.1 and 5.7 mm afterdeflationofpneumoperitoneum(p=0.03),respectively.SurgicalEndoscopyJune2016,Volume30,Issue6,pp23212325测量方法探头的选择和放置1选择高频线阵探头(7.5MHzorgreater).2无菌贴膜覆盖眼球3充分耦合，避免挤压眼球（以面颊或者额头为受力点）4深度在视网膜下1-2cm测量的方法和注意事项1测量位置：位于视网膜和视神经交界处深部3mm2分别测量长轴和短轴的视神经鞘直径并求出平均值。3测量对侧视神经鞘的直径。视神经鞘是颅内硬脑膜与蛛网膜下腔的延续，因此颅内压增高将直接增大视神经鞘直径。测量主要在眼球后3mm处，因为该处随颅内压变化的弹性伸缩性最大。ONSD评估颅内压力测量方法：冠状位测量球后3mm处ONSD,3次均值正常上限值5mm矢状位测量球后3mm处ONSD,3次均值正常上限值5.8mm参考值1、单侧异常ThepresenceofunilateralincreasedONSDsuggestsalateralizingprocess,suchasopticneuritisorcompressiveopticneuropathy.Papilledema（视乳头水肿）mayalsobenotedasopticdiscbulgingintotheretinaandprotrudingintothevitreousbody.2、双侧异常ThecutoffvalueforincreasedONSDcorrelatingwithincreasedICPhasbeendebatable.BasedontheinitialstudyofultrasoundmeasurementofONSD,11manyauthorsciteadiameter5mmaselevatedinpatientsolderthanage4.Tworecentmeta-analysesofsixstudiesevaluatedthecorrelationbetweenONSDandICP20cmH2Oandcalculatedapooledsensitivityandspecificityof8790%and7985%,respectively;however,thecutoffforabnormalONSDvariedfrom5.0to5.9mminthesestudies,withhalfofthestudiesutilizingacutoff5.7mm.谢谢聆听！