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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adolescent, Adult, Aged, Aged, 80 and over, Carpal Tunnel Syndrome, Female, Humans, Male, Median Nerve, Middle Aged, Neural Conduction, Neurologic Examination, Prospective Studies, Sensitivity and Specificity, Ultrasonography, Wrist, Young Adult.
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Sonographic cross-sectional area measurement in carpal tunnel syndrome patients: can delta and ratio calculations predict severity compared to nerve conduction studies? Context: To evaluate the accuracy of two different sonographic median nerve measurement calculations in predicting carpal tunnel syndrome (CTS) severity in a study population with clinically and electrophysiologically confirmed CTS. 643 wrists of 427 patients (325 females and 102 males, age range: 17-90 years, mean ± SD: 57.9 ± 14.7) were included with CTS diagnosis based on clinical and nerve conduction studies (NCS). Cross-sectional area (CSA) measurement of the median nerve was performed at the carpal tunnel level (CSAc) and at the pronator quadratus muscle level (CSAp). Two parameters were calculated: delta (∆-CSA), which is the difference between proximal and distal measurements, and ratio (R-CSA), calculated by dividing distal over proximal measurements. Patients were classified into mild, moderate and severe CTS based upon NCS. The mean ∆-CSA (4.2 ± 2.6, 6.95 ± 2.2 and 10.7 ± 4.9 mm(2)) and mean R-CSA (1.5 ± 0.4, 1.95 ± 0.4 and 2.4 ± 0.7) values were significantly different between all groups (p < 0.001). Optimal cut-off values for ∆-CSA and R-CSA were 6 mm(2) and 1.7, respectively, to distinguish mild from moderate disease, and 9 mm(2) and 2.2, respectively, to distinguish moderate from severe disease.
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Threshold values for the calculated sonographic parameters ∆-CSA and R-CSA are useful in predicting CTS severity compared to NCS.