MRI Neurography Using DTI and Tractography as a Quantitative Tool in the Assessment of Median Nerve in Patients with Carpal Tunnel Syndrome

Abstract

Background: Carpal tunnel syndrome (CTS) is a typical medical problem, the affected patient can feel discomfort, tingling, and numbness in his hand. Ithappens when the nerve is compressed while passing through the wrist. It commonlyaffects obese / or pregnant patients and individualswith rheumatoid disease.Results: In our study, we measured the cross-sectional area (CSA) (mm^2) of the nerve at the outlet and inlet of the carpal tunnel, the mean inlet and outlet were 21.92 ± 7.215, and 14.41 ± 5.051 (mm^2) respectively. Anegative correlation was reported between ADC and FA, FA was lower in CTS patients while ADC was higher in CTS patients. There was a significant difference in The FA and ADC valuesbetween Carpal tunnel patients and healthy patients. The mean FA and ADC valueswere 0.431± 0.064 and 1.237 ± 0.288 respectively. Our study recommends cut-off values for FA and ADC (0.412 and 1.049), so the sensitivity and specificity were noted to be 75% and 80% for FA and 80% and 60% for ADC respectively.Conclusions: MRI neurography using DTI and tractography has a good diagnostic role in the evaluation of patients with CTS.It can be used as a quantitative tool together with changes in the morphology of the nerve by calculating different diffusion values (FA and ADC). Changes in the FA and ADC of the nerve along the carpal tunnel are the primary characteristics of CTS, indicating the level of nerve compression and clinical impairment.