視神經(jīng)鞘直徑與顱內(nèi)壓

1、重癥醫(yī)學(xué)科解剖學(xué)基礎(chǔ)Pulillary aperature 瞳孔Iris 虹膜Cornea 角膜Ciliary body 睫狀體Lens 晶狀體Vitreous body 玻璃體Retina 視網(wǎng)膜Choroid 脈絡(luò)膜Sclera 鞏膜 眼部結(jié)構(gòu)及超聲圖像 眼球及眶周結(jié)構(gòu) 視路MRI圖像 視神經(jīng)：眼內(nèi)部眶部（ONSD段）管內(nèi)部顱內(nèi)部Critical Care 2008, 12:R114ONSD視神經(jīng)ONSD臨界值5.82mm ICP20mmHg 共納入231例敏感性 0.90（95%CI 0.80-0.95）特異性 0.85（95%CI 0.73-0.93）Intensive Care Me

2、d (2011)37:10591068 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. Conclusion This study suggests that ONSD assessment throughout the acute phase ma

3、y 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.影響因素1、 體位 Effects of Prone Position and Positive End-

4、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 meas

5、ure 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 specificit

6、y 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 2 肥胖、氣腹There were 62 subjects, 28 females (45.2 %) and 34 males (

7、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 an

8、d 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, Issue 6, pp 23212325測(cè)量方法探頭的選擇和放置 1 選擇高頻線陣探頭 (7.5 MHz or greater) . 2 無(wú)菌貼膜覆蓋眼球 3 充分耦合，避免擠壓眼球（以面頰或者額頭為受力點(diǎn)） 4 深度在視

9、網(wǎng)膜下1-2cm測(cè)量的方法和注意事項(xiàng) 1 測(cè)量位置：位于視網(wǎng)膜和視神經(jīng)交界處深部3mm 2 分別測(cè)量長(zhǎng)軸和短軸的視神經(jīng)鞘直徑并求出平均值。 3 測(cè)量對(duì)側(cè)視神經(jīng)鞘的直徑。 視神經(jīng)鞘是顱內(nèi)硬腦膜與蛛網(wǎng)膜下腔的延續(xù)，因此顱內(nèi)壓增高將直接增大視神經(jīng)鞘直徑。測(cè)量主要在眼球后3mm處，因?yàn)樵撎庪S顱內(nèi)壓變化的彈性伸縮性最大。ONSD評(píng)估顱內(nèi)壓力測(cè)量方法：冠狀位測(cè)量球后3mm處ONSD,3次均值正常上限值5mm矢狀位測(cè)量球后3mm 處ONSD,3次均值正常上限值5.8mm參考值1、 單側(cè)異常 The presence of unilateral increased ONSD suggests a latera

10、lizing process, such as optic neuritis or compressive optic neuropathy. Papill edema（視乳頭水腫） may also be noted as optic disc bulging into the retina and protruding into the vitreous body.2、 雙側(cè)異常 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