视神经鞘直径与颅内压课件.ppt

视神经鞘直径(ONSD)与颅内压(ICP),重症医学科,1,解剖学基础,2,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,3,4,眼部结构及超声图像 眼球及眶周结构,5,6,视路MRI图像,视神经：眼内部眶部（ONSD段）管内部颅内部,7,8,Critical Care 2008, 12:R114,ONSD,视神经,ONSD临界值5.82mm ICP20mmHg,9,共纳入231例敏感性 0.90（95%CI 0.80-0.95）特异性 0.85（95%CI 0.73-0.93）,Intensive Care Med (2011)37:10591068,10,11,Conclusions Sonographic measurement of ONSD may be a potentially useful technique for assessing IH in a binary mode (present/ absent) when invasive/monitoring methods are not desirable or available.,12,视神经鞘直径可准确评估颅内压增高？,13,14,Conclusion This study suggests that ONSD assessment throughout the acute phase may not be a reliable method to monitor ICP. ONSD expansion can persist even after ICP control, and this may be the reason for ONSD expansions seen in our study even with normal ICPs. Further larger size studies are needed to confirm these findings.,15,影响因素,16,1、 体位,Effects of Prone Position and Positive End-Expiratory Pressure on Noninvasive Estimators of ICP: A Pilot Study.Results: The mean values of ONSD, ICPFVd, and ICPPI significantly increased after change from supine to prone position. Receiver operating characteristic analyses demonstrated that, among the noninvasive methods, the mean ONSD measure had the greatest area under the curve signifying it is the most effective in distinguishing a hypothetical change in ICP between supine and prone positioning (0.86+/-0.034 0.79 to 0.92). A cutoff of 0.43 cm was found to be a best separator of ONSD value between supine and prone with a specificity of 75.0 and a sensitivity of 86.7.Conclusions: Noninvasive ICP estimation may be useful in patients at risk of developing intracranial hypertension who require prone positioning.,Journal of Neurosurgical Anesthesiology. 18 March 2016,17,2 肥胖、气腹,There were 62 subjects, 28 females (45.2 %) and 34 males (54.8 %), with a mean age of 44.22 10.44 years (range 2366). Forty-eight percent of patients were non-obese, and 52 % of patients were obese. The mean body mass index was 30.70 7.61 kg/m2 (range 20.059.5). The mean ONSD of non-obese and obese patients was 4.7 and 5.5 mm at baseline (p = 0.01), 5.4 and 6.2 mm at 15 min (p = 0.01), 5.8 and 6.6 mm at 30 min (p = 0.01), and 5.1 and 5.7 mm after deflation of pneumoperitoneum (p = 0.03), respectively.,Surgical EndoscopyJune 2016, Volume 30, Issue6, pp 23212325,18,测量方法,19,探头的选择和放置,1 选择高频线阵探头 (7.5 MHz or greater) .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,20,21,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。,22,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。,23,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,24,参考值,25,1、 单侧异常,The presence of unilateral increased ONSD suggests a lateralizing process, such as optic neuritis or compressive optic neuropathy. Papill edema（视乳头水肿） may also be noted as optic disc bulging into the retina and protruding into the vitreous body.,26,2、 双侧异常,The cutoff value for increased ONSD correlating with increased ICP has been debatable.Based on the initial study of ultrasound measurement of ONSD,11 many authors cite a diameter 5 mm as elevated in patients older than age 4. Two recent meta-analyses of six studies evaluated the correlation between ONSD and ICP 20 cm H2O and calculated a pooled sensitivity and specificity of 8790% and 7985%, respectively; however, the cutoff for abnormal ONSD varied from 5.0 to 5.9 mm in these studies, with half of the studies utilizing a cutoff 5.7 mm.,27,谢谢聆听！,28,此课件下载可自行编辑修改，供参考！感谢您的支持，我们努力做得更好！,29,