White matter changes in normal pressure hydrocephalus and Binswanger disease: Specificity, predictive value and correlations to axonal degeneration and demyelination

Objectives– To analyse the diagnostic and prognostic value of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH) magnetic resonance imaging (MRI) changes and their relation to symptoms and cerebrospinal fluid (CSF) markers of demyelination (sulphatide) and axonal degeneration [neurofilament triplet protein (NFL)] in a large series of patients with normal pressure hydrocephalus (NPH) and Binswanger disease (BD). Materials and methods– PVH and DWMH were determined by a semi-automatic segmentation method on T2-weighted images in 29 patients with NPH and 17 patients with BD. CSF analyses, psychometric testing and quantification of balance, gait and continence were performed in all patients and also postoperatively in NPH patients. Results– No MRI variable could identify NPH or BD patients. Abundant PVH and DWMH preoperatively correlated with improvement in gait, balance and psychometric performance after shunt surgery (P < 0.05). CSF sulphatide correlated positively with the amount of DWMH (P < 0.05) while NFL was correlated to both PVH and DWMH (P < 0.05). Abundant PVH correlated with poor psychometric performance while DWMH correlated with gait disturbance (P < 0.05). Postoperative reduction in PVH correlated with improvement in gait, balance and psychometric performance. Conclusion– In spite of a refined quantification method, NPH and BD patients exhibited similar MRI changes. MRI had a predictive value in NPH patients. DWMH might relate to demyelination and PVH to neuronal axonal dysfunction. NPH and BD share the major part of symptoms and MRI changes, indicating a common pathophysiological pattern, and we raise the question of how to treat BD patients.