Normal-pressure hydrocephalus: White matter lesions correlate negatively with gait improvement after lumbar puncture

Objectives: To test relations between white matter lesions (WML) load in Normal Pressure Hydrocephalus (NPH) patients and gait characteristics at baseline, duration of symptoms, gait improvement after lumbar puncture (LP), vascular risk factors. Patients: Fifteen idiopathic NPH patients. Methods: Patients underwent a timed walking test, before and after LP. Five gait variables were assessed and improvement percentages were calculated. WML load was rated regionally and globally in T2 weighted MRI images, using a simple visual scale. Spearman or Pearson correlation coefficients were used to test relations between variables. Results: Significant negative correlations were found between WML scores and gait improvement after CSF removal but not with duration of symptoms or gait variables before LP. Conclusions: WML seem to contribute to the irreversibility of symptoms in NPH but not to the pathophysiological mechanisms that lead to them.