Ultrasound Evaluation of Patients with Moderate and Severe Carpal Tunnel Syndrome

Abstract

The objective of this study is to determine cut-off points for the crosssectional areas of the median nerve proximal and distal to carpal tunnel in moderate and severe Carpal Tunnel Syndrome (CTS) and compare the results of our study with those available in the literature. Forty-three patients with upper limb pain other than CTS and 36 patients with idiopathic CTS enrolled into the study. The diagnosis and categorization of CTS were based on electrophysiologic criteria of the American Academy of Neurology. Median nerve cross-sectional areas were measured. Arithmetic mean values and standard deviation of each variable were measured. Student t-test and chi-squared test were applied to compare continuous and dichotomous variables between CTS and non-CTS control groups. Ultimately the diagnostic performances of the test characteristics including sensitivity, specificity, positive and negative predictive values were measured. Mean cross-sectional area of the nerve is higher in moderate than severe CTS proximal and distal to carpal tunnel. We accepted cut-off points of 11.5 mm² and 13.5 mm² for cross-sectional areas of the proximal and distal portions of carpal canal respectively. The sensitivity, specificity, positive and negative predictive values for the proximal inlet are 83%, 90.7%, 65.5% and 55.7%; and for the distal outlet are 36.1%, 93%, 81.2% and 63.4% respectively. We suggest that ultrasound is a good diagnostic modality for patients referred to tertiary care centers which categorized as moderate CTS.

The diagnostic value of ultrasound compared with nerve conduction velocity in carpal tunnel syndrome

“…In this study, they accepted cut‐off points of 11.5 and 13.5 mm² for CSA of the proximal and distal portions of the carpal canal, respectively. The sensitivity, specificity, positive and negative predictive values for the proximal inlet were 83%, 90.7%, 65.5% and 55.7%; and for the distal outlet were 36.1%, 93%, 81.2% and 63.4%, respectively . Kwon et al .…”

“…In this study, the difference in CSA of the median nerve in mild, moderate and severe CTS was not statistically significant ( P = 0.2) either in the carpal tunnel inlet or outlet . Moghtaderi et al . suggested that ultrasound is a good diagnostic modality for patients referred to tertiary care centers with categorization as moderate CTS.…”

Idiopathic Carpal Tunnel Syndrome: Evaluation of the Depth of the Carpal Tunnel by Ultrasonography

“…In many studies, it has been used to evaluate CTS through measurement of median nerve cross-sectional area (CSA) and calculation of the flattening ratio (FR) (Visser et al 2008). Sonographic measures of CTS are usually obtained at the inlet level, as it is believed that measures at the outlet are technically more difficult and have less inter-rater reliability, though the sensitivity and specificity at both levels are comparable (Moghtaderi et al 2012;Moran et al 2009). …”

Ultrasonography in evaluating the character of lesions of the median nerve in carpal tunnel syndrome

“…Назначена ЭНМГ верхних конечностей. Амбула-торно в условиях отделения функциональной диагности-сле выхода из запястного канала выявляет значимые из-менения структуры и утолщение ствола нерва [8].…”

“…Оптимальной при СЗК является зона запястного канала, объективным параметром неврального пораже-ния -площадь поперечного сечения ствола нерва [7,8]. Остается спорным вопрос о возможности применения УСИ для диагностики степени и характера поражения ствола нерва при СЗК.…”