Application of diffusion tensor imaging scanning of conus medullaris in lower urinary tract dysfunction / 中国康复理论与实践

ABSTRACT

Objective To investigate the signal abnormality of conus medullaris in patients with overactive bladder(OAB)and un-deractive bladder(UAB)by MRI diffusion tensor imaging(DTI). Methods From May,2021 to April,2023,23 patients with lower urinary tract dysfunction without trauma and supraspi-nal lesions were enrolled(case group).All patients underwent imaging urodynamics and pelvic floor electromy-ography.Based on the bladder contraction during the filling phase of urodynamics,the patients were divided into UAB group and OAB group.Eight healthy subjects were included as the control group.All participants under-went T10 to L5 spinal segment MRI scans and DTI scans.The position of conus medullaris was determined by comparing the DTI sequences with the MRI scans.The fractional anisotropy(FA),apparent diffusion coefficient(ADC),and relative anisotropy(RA)of the conus medullaris intermediate segment were compared. Results Twelve cases were in UAB group,and eleven in OAB goup.Abnormalities were found in the pelvic floor elec-tromyography in the case group.There was significant difference in sacral reflex arc nerve conduction testing be-tween UAB and OAB groups(P = 0.036).Compared with the control group,ADC increased(t = 2.185,P = 0.037)in the case group;FA decreased(t = 3.439,P = 0.005)and ADC increased(t = 4.582,P<0.001)in UAB group. Conclusion DTI is helpful to find the potential lesion of spinal cord in patients with lower urinary tract dysfunction.FA and ADC are valuable indicators for the diagnosis of conus medullaris injury.