Department of Clinical Neuroscience, Umeå University, SE-901 85 Umeå, Sweden.
Neurology. 2011 Mar 8;76(10):903-9. doi: 10.1212/WNL.0b013e31820f2dd0.
The intracranial pressure (ICP) and CSF outflow resistance (R(out)) are essential to describe the dynamics of the CSF system. R(out) affects ICP, pulse amplitudes, CSF absorption, and the compliance of the system. The objective of this study was to determine the reference values in healthy elderly subjects.
Elderly people (60-82 years), who considered themselves healthy, were recruited through an advertisement in the local newspaper. All were evaluated with a 3-T MRI. Subjects were eligible if they did not have any psychiatric or neurologic disorder or signs of advanced atherosclerotic disease. CSF resting pressure (ICP) and R(out) were determined by a constant pressure infusion method with the patient in the supine position. The study population consisted of 40 subjects (mean age 70 years; 23 women).
The median ICP was 11.6 mm Hg (15.8 cmH(2)O) and the reference interval was ICP 7.8-14.3 mm Hg (10.6-19.4 cmH(2)O) (defined as 5th to 95th percentiles). The median R(out) was 8.6 mm Hg/mL/min. The variation in R(out) was large and not normally distributed. The 90th percentile of R(out) was 17.4 mm Hg/mL/min.
This study reports reference values for ICP and R(out) and should be used for comparison when investigating disorders with suspected CSF dynamic disturbances in the elderly. ICP was in the same range as that reported in the young and middle-aged. The upper limit of R(out) was higher than previously believed to be the upper limit of normal for this age group.
颅内压（ICP）和脑脊液流出阻力（R(out)）对于描述脑脊液系统的动力学至关重要。R(out) 会影响 ICP、脉冲幅度、脑脊液吸收和系统顺应性。本研究旨在确定健康老年受试者的参考值。
通过在当地报纸上刊登广告，招募认为自己健康的老年人。所有受试者均接受 3T MRI 检查。如果受试者没有精神或神经障碍或有进展性动脉粥样硬化疾病的迹象，则有资格参加研究。通过患者仰卧位下的恒压输注法确定脑脊液静息压力（ICP）和 R(out)。研究人群包括 40 名受试者（平均年龄 70 岁；23 名女性）。
中位 ICP 为 11.6mmHg（15.8cmH(2)O），参考区间为 ICP 7.8-14.3mmHg（10.6-19.4cmH(2)O）（定义为第 5 至 95 百分位数）。中位 R(out)为 8.6mmHg/mL/min。R(out)的变化较大且呈非正态分布。R(out)的第 90 百分位数为 17.4mmHg/mL/min。
本研究报告了 ICP 和 R(out)的参考值，在调查怀疑有老年 CSF 动力学障碍的疾病时，应将其用于比较。ICP 与年轻和中年人群报告的范围相同。R(out)的上限高于之前认为的该年龄段的正常上限。
