Carpal tunnel syndrome assessment with diffusion tensor imaging: Value of fractional anisotropy and apparent diffusion coefficient

• Published in: European radiology Vol. 28; no. 3; pp. 1111 - 1117
• Main Authors: Klauser, A. S., Abd Ellah, M., Kremser, C., Taljanovic, M., Schmidle, G., Gabl, M., Cartes-Zumelzu, F., Steiger, R., Gizewski, E. R.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.03.2018; Springer Nature B.V
• Subjects: Adult; Aged; Anisotropy; Carpal tunnel syndrome; Carpal Tunnel Syndrome - diagnostic imaging; Case-Control Studies; Diagnosis; Diagnostic Radiology; Diffusion; Diffusion coefficient; Diffusion Tensor Imaging - methods; Female; Humans; Image Interpretation, Computer-Assisted - methods; Imaging; Internal Medicine; Interventional Radiology; Magnetic Resonance; Magnetic resonance imaging; Male; Median Nerve - diagnostic imaging; Medicine; Medicine & Public Health; Middle Aged; Nerve conduction; Neural Conduction; Neuroradiology; Observer Variation; Overuse injuries; Patients; Radiology; Sensitivity; Sensitivity and Specificity; Ultrasound; Functional magnetic resonance imaging; Carpal tunnel syndrome; Magnetic resonance imaging; Median nerve; Diffusion tensor imaging
• ISSN: 0938-7994; 1432-1084; 1432-1084
• DOI: 10.1007/s00330-017-5046-y

Objectives To quantitatively assess carpal tunnel syndrome (CTS) with DTI by evaluating two approaches to determine cut-off values. Methods In forty patients with CTS diagnosis confirmed by nerve conduction studies (NCs) and 14 healthy subjects (mean age 58.54 and 57.8 years), cross-sectional area (CSA), apparent diffusion coefficient (ADC) and fractional anisotropy (FA) at single and multiple levels with intraobserver agreement were evaluated. Results Maximum and mean CSA and FA showed significant differences between healthy subjects and patients (12.85 mm 2 vs. 28.18 mm 2 , p < 0.001, and 0.613 vs. 0.524, p =0.007, respectively) (10.12 mm 2 vs. 19.9 mm 2 , p <0.001 and 0.617 vs. 0.54, p =0.003, respectively), but not maximum and mean ADC ( p > 0.05). For cut-off values, mean and maximum CSA showed the same sensitivity and specificity (93.3 %). However, mean FA showed better sensitivity than maximum FA (82.6 % vs. 73.9 %), but lower specificity (66.7 % vs. 80 %), and significant correlation for maximum CSA, 97 % ( p < 0.01), with good correlation for maximum ADC and FA, 84.5 % ( p < 0.01) and 62 % ( p =0.056), respectively. Conclusions CSA and FA showed significant differences between healthy subjects and patients. Single measurement at maximum CSA is suitable for FA determination. Key Points • DTI showed that FA is stronger than ADC for CTS diagnosis . • Single- and multiple-level approaches were compared to determine FA and ADC. • Single-level evaluation at the thickest MN cross-sectional area is sufficient.