Chan Division of Occupational Science and Occupational Therapy, University of Southern California, 1640 Marengo St, Suite 505, Los Angeles, CA, 90089-9256, USA.
Norris Medical Library, University of Southern California, Los Angeles, CA, USA.
Syst Rev. 2019 Jan 3;8(1):2. doi: 10.1186/s13643-018-0929-9.
Median nerve cross-sectional area (CSA) is the primary sonographic parameter for assessing and diagnosing median nerve pathology, such as carpal tunnel syndrome. However, variability in the sensitivity of diagnostic thresholds exists, which may be due to a lack of standardized normative reference values. Current estimates of normal median nerve CSA stem largely from small studies using a local pool of healthy controls. A systematic review and meta-analysis will be conducted to identify all available data for median nerve CSA in healthy, asymptomatic individuals to create a comprehensive set of normative reference values.
Articles that include sonographic measures of median nerve CSA will be identified through a rigorous search of published evidence, a hand search through tables of contents of key journals, and the gray literature, including ClinicalTrials.gov and conference abstracts. Each abstract and full text will be reviewed by multiple raters to identify studies from 2000 to present that include original data. Any study that provides median nerve CSA values from healthy individuals will be included (e.g., reference value study, control participants in a diagnostic study). Studies will be assessed for quality using a modified version of the National Institute of Health Study Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies, with primary focus on the use of a detailed and acceptable image acquisition and analysis protocol. Using data from included studies, reference values will be calculated for median nerve CSA by anatomical regions, including the distal forearm, wrist, and carpal tunnel at the level of the pisiform. Reference values will be stratified by gender, ethnicity, and age based upon the specificity of the data provided by the included articles.
A comprehensive set of normative reference values of median nerve CSA will reduce variability across studies, allowing future research to more accurately evaluate and establish diagnostic thresholds. Additionally, normative values can serve as a reference for evaluating treatment outcomes and provide a means to investigate and understand minor nuances in CSA changes that may be indicative of preclinical stages of median nerve pathology.
PROSPERO 2016 CRD42016037286.
正中神经横截面积（CSA）是评估和诊断正中神经病变（如腕管综合征）的主要超声参数。然而，诊断阈值的敏感性存在变异性，这可能是由于缺乏标准化的规范参考值。目前对正常正中神经 CSA 的估计主要来自使用局部健康对照组的小研究。将进行系统评价和荟萃分析，以确定所有关于健康无症状个体正中神经 CSA 的可用数据，以创建一套全面的规范参考值。
通过严格搜索已发表的证据、通过目录搜索关键期刊的表和灰色文献（包括 ClinicalTrials.gov 和会议摘要），将确定包含正中神经 CSA 超声测量值的文章。每个摘要和全文将由多名评审员进行审查，以确定从 2000 年至今包含原始数据的研究。任何提供健康个体正中神经 CSA 值的研究都将包括在内（例如，参考值研究，诊断研究中的对照参与者）。研究将使用国家卫生研究院观察性队列和横断面研究质量评估工具的修改版本进行评估，主要重点是使用详细且可接受的图像采集和分析协议。使用纳入研究的数据，将根据纳入文章提供的数据的特异性，按解剖区域计算正中神经 CSA 的参考值，包括远端前臂、手腕和舟状骨水平的腕管。参考值将按性别、种族和年龄分层。
一套全面的正中神经 CSA 规范参考值将减少研究之间的变异性，使未来的研究能够更准确地评估和建立诊断阈值。此外，规范值可以作为评估治疗效果的参考，并提供一种方法来研究和理解 CSA 变化的细微差异，这些差异可能表明正中神经病变的临床前阶段。
PROSPERO 2016 CRD42016037286。
