Ultrasonography of Median Nerve and Electrophysiologic Severity in Carpal Tunnel Syndrome

Abstract

ObjectiveTo investigate the correlation of the ultrasonographic wrist-to-forearm median nerve area ratio (WFR) and cross sectional area of median nerve at the wrist (CSA-W) to the electrophysiologic severity in patients with carpal tunnel syndrome (CTS).MethodOne hundred and ten wrists electrophysiologically graded as mild, moderate, and severe CTS and 38 healthy controls underwent ultrasonography of median nerve at the distal wrist crease and mid-forearm. WFR and CSA-W were analyzed according to the severity of CTS.ResultsWFR was 1.12±0.14, 1.91±0.33, 2.27±0.47 and 3.02±0.97 and the CSAs-W was 7.23±1.67 mm2, 13.51±3.72 mm2, 14.67±2.93 mm2, and 18.74±6.01 mm2 in controls, mild (n=28), moderate (n=46), and severe (n=36) CTS, respectively. CSA-W displayed significant differences between the control and the mild CTS, moderate CTS and severe CTS groups. However, there was no significant difference between mild CTS and moderate CTS groups. WFR revealed significant difference between all groups. The sensitivity and specificity of the WFR in grading the severity of CTS were higher than those of the CSA-W.ConclusionUltrasonography is a useful complementary tool for the evaluation of CTS. Both WFR and CSA-W are highly correlated with severity grade of CTS. However, WFR is superior to CSA-W for diagnosis and grading of the severity of CTS.

Sonographic cross-sectional area measurement in carpal tunnel syndrome patients: can delta and ratio calculations predict severity compared to nerve conduction studies?

“…Several studies have calculated a ratio between a proximal measurement of the median nerve at the mid forearm and a distal measurement of the median nerve at the carpal tunnel inlet (R-CSA) [9,10]. Other studies have suggested using the CSA difference between a proximal median nerve measurement at the level of the pronator quadratus and a measurement within the carpal tunnel, resulting in a delta CSA (Δ-CSA).…”

“…An emerging role for ultrasound (US) in the diagnosis of CTS has been described in the past few years [6][7][8][9][10].…”

Ultrasonography of Median Nerve in Carpal Tunnel Syndrome before and after Hormone Replacement in Patients with Hypothyroidism

“…Also, Tengfei et al [34] , reported that, the mean inlet CSA was 8.7 mm 2 in healthy controls and 14.6 mm 2 in CTS. Additionally, Andrea et al [35] , reported that distal CSA was 16.8 mm 2 , Seok et al [36] found that the distal CSA were significantly different from mild, moderate to severe (13. ) cases of carpal tunnel syndrome respectively.…”

“…In the current study, the means of proximal CSA were 9.6 and 9.9 mm 2 in right and left median nerve respectively, ranging from 8.6 to 11.4 mm 2 . Seok et al [36] reported that proximal CSAs for mild, moderate and severe were 7.14 mm 2 , 6.57 mm 2 and 6.39 mm 2 . Moreover, Andrea et al [35] found only a small difference in proximal CSA between the patients (9.5 mm 2 ± 1.9) and the control subjects (8.7 mm 2 ± 1.6) and the proximal nerve to be slightly larger in the patients.…”

Carpal Tunnel Syndrome in Patients with and without Diabetes Mellitus in Upper Egypt: The Impact of Electrophysiological and Ultrasonographical Studies

“…The median nerve was examined in the transverse and longitudinal planes along the carpal tunnel by gray scale US to investigate the presence of median nerve compression criteria, including the measurement of cross sectional area (CSA) and flattening ratio of median nerve. The cut-off value of cross-sectional area at the tunnel inlet was 9.5 mm 2 Kang et al [13].…”