Objective: To evaluate the association of the ultrasonographic optic nerve sheath diameter (ONSD) and intracranial pressure (ICP), and the feasibility of ultrasonographic ONSD in predicting high ICP. Methods: A prospective study. The outpatients who planned to measure ICP by lumbar puncture in Department of Neurology, Xuanwu Hospital, Capital Medical University were selected from January 2011 to May 2012. All the retrobulbar ONSD measurement with B-scan ultrasound was performed just before lumbar puncture. When high ICP was defined as ICP more than 200 mmH2O(1 mmH2O=0.009 8 kPa), the participants were divided into the high ICP group and the normal ICP group. The Pearson correlation coefficient analysis was used to analyze the correlation between ICP and postbulbar ONSD measurements. The difference in ONSD was compared between the high ICP and normal ICP groups with the t test. The receiver operating characteristic (ROC) curve was used to calculate the cutoff value of mean ONSD and evaluate the sensitivity and specificity of the method. Results: A total of 130 participants were involved in this study. There were 71 males and 59 females, aged (38±14) years.The mean ICP was (209.84±79.99) mmH2O. The mean ONSD was (5.68±0.78) mm in the right eyes, (5.78±0.78) mm in the left eyes, and (5.73±0.71) mm in both eyes. The ICP had a significant correlation with ONSD in the right eyes (r=0.54, P<0.001), ONSD in the left eyes (r=0.56, P<0.001) and ONSD in both eyes (r=0.60, P<0.001), but no correlation with age (r=-0.14, P=0.114) and gender (r=0.20, P=0.817). The ONSD in the high ICP group (n=65) was (6.11±0.66) mm, (6.22±0.56) mm and (6.17±0.50) mm in the right eyes, left eyes, and both eyes, respectively. Compared with the ONSD in the normal ICP group (n=65), which was (5.26±0.64) mm in the right eyes, (5.34±0.72) mm in the left eyes and (5.30±0.62) mm in both eyes, there was a significantly enlarged ONSD in the high ICP group (t=-7.507, -7.778, -8.779, all P<0.001). The ROC analysis showed the ONSD of 5.6 mm was the best cutoff value with a sensitivity of 86% and a specificity of 71% for identifying high ICP. Conclusions: There is a significantly positive correlation between ICP and postbulbar ONSD measured by ultrasound. This non-invasive method may be an alternative approach to predicting the ICP value of patients whose ICP measurement via lumbar puncture is at high risk. However, it can not replace the direct ICP measurement with the invasive method. (Chin J Ophthalmol, 2018, 54: 683-687).
目的： 研究超声测量球后视神经鞘直径（ONSD）和颅内压之间的相关性，评价该方法预测颅内压升高的可行性。 方法： 前瞻性研究。选取2011年1月至2012年5月在首都医科大学宣武医院神经内科门诊计划进行腰椎穿刺颅内压测量的患者。所有受检者在施行腰椎穿刺颅内压测量前完成双眼球后3 mm处ONSD的超声测量。根据腰椎穿刺颅内压测量结果，以颅内压>200 mmH2O（1 mmH2O=0.009 8 kPa）作为颅内压升高的标准，将受检者分为高颅压组和正常颅压组。采用Pearson相关系数分析法分析双眼球后ONSD测量值与颅内压之间的相关性，采用t检验比较高颅压组与正常颅压组之间ONSD的差异，采用受试者工作特征（ROC）曲线分析超声测量ONSD诊断高颅压的最佳临界值，并评估该方法的敏感性和特异性。 结果： 共130例受检者纳入研究，男性71例，女性59例，年龄（38±14）岁。130例受检者腰椎穿刺测得的颅内压为（209.84±79.99）mmH2O；B型超声测得的ONSD值，右眼为（5.68±0.78）mm，左眼为（5.78±0.78）mm，双眼平均值为（5.73±0.71）mm。颅内压与右眼ONSD（r=0.54, P<0.001）、左眼ONSD（r=0.56, P<0.001）和双眼平均ONSD（r=0.60, P<0.001）均呈正相关，而与年龄（r=-0.14, P=0.114）和性别（r=0.20, P=0.817）之间无相关性。高颅压组65例受检者，右眼ONSD为（6.11±0.66）mm，左眼ONSD为（6.22±0.56）mm，双眼平均ONSD为（6.17±0.50）mm；正常颅压组65例受试者，右眼ONSD为（5.26±0.64）mm，左眼ONSD为（5.34±0.72）mm，双眼平均ONSD为（5.30±0.62）mm；高颅压组右眼、左眼及双眼平均ONSD均大于正常颅压组（t=-7.507、-7.778、-8.779，均P<0.001）。ROC曲线得到ONSD诊断高颅压的最佳临界值为5.6 mm，诊断的敏感度为86%，特异度为71%。 结论： 超声测量球后ONSD与颅内压之间具有显著正相关，在急诊及腰椎穿刺检查不能施行的情况下，其可能作为一种替代测量方法，但该方法不能取代有创的颅内压测量。（中华眼科杂志，2018，54：683-687）.
Keywords: Intracranial pressure; Neurilemma; Optic nerve; Ultrasonography.