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Proton magnetic resonance spectroscopy (1H-MRS) provides a non-invasive, in vivo insight into the brain metabolism, and has been successfully used in several neurological conditions. Our objective was to characterise the cerebral metabolic changes in dementia with Lewy bodies (DLB) patients using 1H-MRS. Single Voxel 1H-MRS was performed in 12 DLB patients with mild to moderate symptoms and 11 age-matched healthy controls. Volumes of interest (VOI) were selected, including white matter (WM) in the centrum semiovale and grey matter (GM) in the parasagittal parietal cortex. Main metabolic peaks corresponding to N-acetylaspartate (NAA), glutamate/glutamine (Glx), choline-containing compounds (Cho), myo-inositol (Ins), and creatine plus phosphocreatine (Cr) were identified. These areas were measured and referred to that of the water. Metabolic ratios among the different peak areas were also calculated. In comparison with the control group, DLB patients showed significantly lower mean NAA/Cr, Glx1/Cr and Cho/Cr ratios in the WM, while their Ins/Cr and Ins/NAA ratios did not differ from those of the control group. In the GM, no significant differences were found between both groups. Correlations between age at onset, disease duration, Mini-Mental State Examination, the motor section of the Unified Parkinson’s Disease Rating Scale, Hoehn and Yahr staging and metabolic ratios, both for WM and GM, were not significant in DLB patients. Our spectroscopy data show WM involvement, along with GM preservation, in DLB patients with early or intermediate stages. Hence, 1H-MRS may provide adjunctive information in the ante-mortem diagnosis of DLB.

White matter changes (WMC), detected by imaging techniques, are frequent in stroke patients. The aim of the study was to determine how WMC relate to stroke subtypes and to stroke outcome. We made a systematic Medline search for articles appearing with two of the following key words: either ‘WMC or white matter lesions or leukoencephalopathy or leukoaraiosis’ and ‘stroke or cerebral infarct or cerebral hemorrhage or cerebrovascular disease or transient ischemic attack (TIA)’. WMC, as defined radiologically, are present in up to 44% of patients with stroke or TIA and in 50% of patients with vascular dementia. WMC are more frequent in patients with lacunar infarcts, deep intracerebral hemorrhages, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and cerebral amyloid angiopathy. After an acute ischemic stroke, WMC are associated with a higher risk of death or dependency, recurrent stroke of any type, cerebral bleeding under anticoagulation, myocardial infarction, and poststroke dementia. WMC in stroke patients are often associated with small-vessel disease and lead to a higher risk of death, and poor cardiac and neurological outcome. However, several questions remain open and need further investigations.

Since the recognition of white matter changes on CT (leukoaraiosis), rating scales for the location and severity of white matter changes have been developed, mainly for research purposes, to investigate factors such as the relation with cognition, risk factors, and pathology. The main purpose of rating scales is to provide scores that can be used in statistical analyses. The development of the NINDS-AIREN criteria for vascular dementia have introduced a new application for these rating scales in investigating and delineating the amount of white matter changes on CT/MRI sufficient to fulfill the criteria. Furthermore, in Alzheimer’s disease, recognition of white matter changes may serve to delineate homogeneous groups and help to identify patients with different symptomatology. We reviewed the existing rating scales for CT and MRI and judged their properties and reliability. The ideal rating scale does not yet exist, but different rating scales may serve different purposes, for which some recommendations are made.

Since the recognition of white matter changes on CT (leukoaraiosis), rating scales for the location and severity of white matter changes have been developed, mainly for research purposes, to investigate factors such as the relation with cognition, risk factors, and pathology. The main purpose of rating scales is to provide scores that can be used in statistical analyses. The development of the NINDS-AIREN criteria for vascular dementia have introduced a new application for these rating scales in investigating and delineating the amount of white matter changes on CT/MRI sufficient to fulfill the criteria. Furthermore, in Alzheimer's disease, recognition of white matter changes may serve to delineate homogeneous groups and help to identify patients with different symptomatology. We reviewed the existing rating scales for CT and MRI and judged their properties and reliability. The ideal rating scale does not yet exist, but different rating scales may serve different purposes, for which some recommendations are made.