What Clinical Parameter Strongly Associates White Matter Tract Alterations in a Multiple Sclerosis Population With Voiding Dysfunction? A Prospective Exploratory Study

Abstract

Purpose: To correlate clinical and urodynamics parameters in patients with multiple sclerosis (MS) presenting lower urinary tract symptoms (LUTS) with both Expanded Disability Status Scale (EDSS) and changes in white matter integrity as seen on diffusion tensor images (DTIs). LUTS worsen throughout MS, as does lesion burden. We investigated which symptoms correlated best with structural changes in the white matter structure. Materials and Methods: Ten adult women >18 years were recruited with stable MS for ≥ 3 months and voiding dysfunction defined as % of post-void residual/bladder volume (%PVR/BV) > 20%. Patients participated in a clinical Urodynamic Study and completed several questionnaires (ie, Hamilton Rating Scale, American Urologic Association Symptom Score, NBS-QoL). DTI images were acquired using a 7-Tesla Siemens MAGNETOM Terra MRI scanner. DTI maps were constructed, and individual patients were coregistered with the International Consortium of Brain Mapping-DTI-81 white matter atlas to extract fractional anisotropy and mean diffusivity (MD). Pearson's correlation test was performed between each white matter tracts (WMT) and clinical parameters and between clinical parameters and the EDSS score as well. P < 0.05 was considered significant. Results: Of the clinical parameters, %PVR/BV obtained from the average of multiple un-instrumented uroflow assessments had significant correlations with the greatest number of WMTs. Furthermore, we observed that in all recorded clinical parameters, %PVR/BV was the only significant parameter correlated with the EDSS score. Conclusion: This study demonstrates that %PVR/BV can be used as an objective parameter to gauge WMT changes and disease progression in patients with MS. Future studies are needed to refine this model.