Gonzalez-Suarez Consuelo B, Buenavente Lorraine D, Cua Ronald Christopher A, Fidel Maria Belinda C, Cabrera Jan-Tyrone C, Regala Carina Fatima G
Department of Physical Medicine and Rehabilitation, Faculty of Medicine and Surgery, University of Santo Tomas, San Pablo, Laguna, Philippines.
Department of Physical Medicine and Rehabilitation, University of Santo Tomas Hospital, Manila, Philippines.
J Med Ultrasound. 2018 Jan-Mar;26(1):14-23. doi: 10.4103/JMU.JMU_2_17. Epub 2018 Mar 28.
Electrophysiologic studies have been considered the "gold standard" in diagnosing carpal tunnel syndrome (CTS); however, reports of false-negative results, as well as discomfort for the patient during the procedure has paved the use of ultrasound, being a painless and cost-efficient tool, as an alternative means for its diagnosis. Various ultrasound parameters assessing the median nerve and wrist dimensions have been described, but description of landmarks to assess these in a reliable manner has been lacking.
A systematic search of different databases yielded data regarding ultrasound parameters for CTS diagnosis, the landmarks used, and presence of reliability testing. Based on this, three sonologists discussed the external and sonographic landmarks that will be used in measuring the median nerve measurements, bowing of the flexor retinaculum and the carpal tunnel dimensions. A pilot test with two consecutive healthy participants using the discussed ultrasound parameters was carried out, and results were subjected to inter- and intra-rater reliability testing. Modifications were accordingly made on the acquisition of ultrasound image using external landmarks. The reliability testing proper was done with ten consecutive healthy participants.
Based on the systematic review and the pilot study, external landmarks were used to locate the median nerve in the forearm, carpal tunnel inlet and outlet. For the forearm measurement, it was taken 10 cm proximal from the distal palmar crease. The distal palmar crease was the external landmark used for the carpal tunnel inlet, while for the carpal tunnel outlet; it was measured 1 cm distal to the distal palmar crease. Instead of using the inner edge of the hook of hamate and trapezium, the apices of these bones were used as the landmarks in measuring the carpal tunnel outlet dimensions. There was excellent intra-rater reliability (mid-forearm, carpal tunnel inlet and outlet) except for the following: cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet and outlet; and bowing of the flexor retinaculum. All the parameters had an excellent inter-rater reliability measured at the three levels (intraclass correlation [ICC]: Of 0.77-0.99) except for CSA of the median nerve at the levels of the forearm (fair-to-good with ICC of 0.71) and the carpal tunnel inlet (fair-to-good reliability of ICC: 0.43).
There was an improved inter- and intra-rater reliability when external landmarks were used instead of sonographic landmarks.
电生理研究一直被视为诊断腕管综合征（CTS）的“金标准”；然而，关于假阴性结果的报道以及该检查过程中患者的不适促使超声作为一种无痛且经济高效的工具被用于替代诊断。已经描述了各种评估正中神经和腕部尺寸的超声参数，但缺乏以可靠方式评估这些参数的标志点的描述。
对不同数据库进行系统检索，获取有关CTS诊断的超声参数、所使用的标志点以及可靠性测试情况的数据。基于此，三位超声科医生讨论了用于测量正中神经尺寸、屈肌支持带弯曲度和腕管尺寸的外部和超声标志点。对两名连续的健康参与者使用所讨论的超声参数进行了预试验，并对结果进行了评分者间和评分者内可靠性测试。相应地对使用外部标志点获取超声图像的方法进行了修改。对十名连续的健康参与者进行了正式的可靠性测试。
基于系统评价和预试验，使用外部标志点在前臂、腕管入口和出口处定位正中神经。在前臂测量中，在远侧掌横纹近端10厘米处进行。远侧掌横纹是用于腕管入口的外部标志点，而对于腕管出口，在远侧掌横纹远端1厘米处进行测量。在测量腕管出口尺寸时，使用这些骨头的顶点作为标志点，而不是钩骨和大多角骨的内缘。除以下情况外，评分者内可靠性极佳（前臂中部、腕管入口和出口）：腕管入口和出口处正中神经的横截面积（CSA）；以及屈肌支持带的弯曲度。除前臂水平（ICC为0.71，一般到良好）和腕管入口水平（ICC可靠性一般到良好：0.43）的正中神经CSA外，所有参数在三个水平上的评分者间可靠性都极佳（组内相关系数[ICC]：0.77 - 0.99）。
使用外部标志点而非超声标志点时，评分者间和评分者内可靠性得到了提高。
