Background: Carpal Tunnel Syndrome (CTS) is the most common peripheral neuropathy of an upper extremity. The diagnosis of CTS is commonly based on findings from the medical history, physical examination, and provocative tests. To confirm the diagnosis, some clinician accepts Electrophysiological Studies (EPS) as the reference standard. Diffusion-Tensor Imaging (DTI) is a subtype of diffusion-weighted imaging based on measurement of molecular diffusion along multiple directions in space. Directional anisotropy of water diffusibility can be quantified by imaging indices such as Apparent Diffusion Coefficient (ADC) and Fractional Anisotropy (FA) used to characterize the degree of diffusion anisotropy. Aim of Work: The aim of this study is to study the efficacy of diffusion tensor imaging in the diagnosis of carpal tunnel syndrome. Material and Methods: Twenty-three wrists of 15 healthy subjects and 47 wrists of 31 CTS patients were evaluated with DTI and EPS. FA and ADC of the median nerve were calculated at four locations: Distal radioulnar joint, pisiform bone, hamate bone and hamate hook, and also determined from the whole median nerve. Electrophysiological test, including nerve conduction velocity was also performed for comparison with clinical assessment as a standard of reference. Results: There was a significant difference between healthy individuals and patients with carpal tunnel syndrome (p<0.01 for both FA and ADC). FA value less than 0.54 and ADC value more than 1.19 X 1 0-3 mm 2 /sec might be used in the diagnosis of carpal tunnel syndrome. As regards the DTI results, the sensitivity, specificity, negative predictive value, positive predictive value and accuracy were 97.8%, 95.6%, 95.6%, 97.8% and 97.1% respectively. Conclusion: DTI scan contribute to carpal tunnel syndrome diagnosis on the basis of FA and ADC measurements.

Background: Carpal Tunnel Syndrome (CTS) is the most common peripheral neuropathy of an upper extremity. The diagnosis of CTS is commonly based on findings from the medical history, physical examination, provocative tests and Electrophysiological Studies (EPS) as the reference standard, but in some cases the results may be equivocal due to discrepancies in the different measured clinical parameters. Imaging has the potential to resolve these discrepancies. Fat-saturated, T2-weighted Magnetic Resonance Imaging (MRI) can reveal morphological changes in CTS patients, such as nerve enlargement, nerve flattening, increased nerve signal intensity, and bowing of the flexor retinaculum. Aim of Work:The aim of this study is to study the role of conventional MRI in the diagnosis of Carpal Tunnel Syndrome (CTS). Patients and Methods:Twenty-three wrists in 15 healthy subjects and 47 wrists in 31 CTS patients were evaluated with MRI and Electrophysiological Studies (EPS). The qualitative and quantitative analysis of MRI include: (1) The high signal intensity of the Median Nerve (MN) on the T2W and PD fat suppressed weighted images, (2) Flexor Retinaculum (FR) bowing and measurements of its height and area, (3) Flattening ratio of the MN, (4) MN CSA. EPS; including nerve conduction velocity was also performed for comparison with clinical assessment as a standard of reference.Results: There was a significant difference between healthy individuals and patients with CTS for all qualitative and quantitative MRI interpretation. This includes, the higher SI of the MN on both T2 and PD WIs, the greater FR bowing area and height, the higher flattening ratio of the MN at CT and the greater value of MN CSA. As regards the MRI results, the sensitivity, specificity, negative predictive value, positive predictive value and accuracy were 97.8%, 95.6%, 95.6%, 97.8% and 97.1% respectively.Conclusion: MRI can contribute to carpal tunnel syndrome diagnosis on the basis of its qualitative and quantitative measurements.