Evaluating Various Ultrasound Criteria for Determining Carpal Tunnel Syndrome Severity

Objective: This study aimed at assessing the value of a variety of ultrasound criteria for grading carpal tunnel syndrome (CTS) severity. Methods: Ultrasound evaluations were conducted on confirmed CTS patients by an experienced radiologist, blinded to NCS results. Cross-sectional area (CSA) at pronator quadratus muscle, carpal tunnel inlet and outlet, echogenicity, transverse motion during flexion, flattening ratio, and thickening of the flexor retinaculum were measured. Results: Decreased echogenicity of the median nerve was notably observed as a distinguishing feature between mild and moderate cases. Decreased nerve movement was significantly more prevalent in severe CTS cases. No significant differences were found in the median nerve flattening ratio or flexor retinaculum thickness. Bowing at the inlet showed significant differences. CSA at the inlet and outlet indicated severe CTS with significant differences. Conclusion: The findings highlight the importance of using multiple sonographic criteria for accurate diagnosis and treatment, although no significant differences were noted in the median nerve flattening ratio and flexor retinaculum thickness.