Subject(s)
Dyskinesias , Lower Extremity/physiopathology , Myalgia , Neuromuscular Agents/administration & dosage , Botulinum Toxins, Type A/administration & dosage , Dyskinesias/diagnosis , Dyskinesias/drug therapy , Dyskinesias/physiopathology , Humans , Male , Middle Aged , Myalgia/diagnosis , Myalgia/drug therapy , Myalgia/physiopathology , Syndrome , Toes/physiopathologyABSTRACT
Eleven consecutive patients with a first episode of acute optic neuritis were evaluated, using conventional and magnetization transfer (MT) magnetic resonance imaging (MRI), in order to assess the temporal evolution of optic nerve (ON) damage and to investigate the correlation of ON damage with visual outcome and electrophysiological parameters. Patients underwent neuroophthalmological, neurological, electrophysiological, and MRI assessments at baseline and after three and 12 months. ON volumes were measured on coronal T1-weighted images using a local thresholding segmentation technique. MT ratio (MTR) from the ON was derived from gradient echo images. No significant volume difference was detected between affected and healthy ON, both at baseline and follow-up. At baseline, mean MTR values were significantly higher in affected ON than in healthy ON (P =0.001), whereas at months 3 and 12, the mean MTR values were significantly reduced in the affected ON (P =0.02 and 0.003, respectively). Mean MTR of the affected ON, corrected for healthy ON values, progressively decreased over time (P =0.04 at month 3 and P =0.0012 at month 12). On the contrary, MTR values of healthy ON remained stable. No correlations were found between MTR measures and clinical or electrophysiological data. This study shows the presence of subtle pathological changes, possibly due to residual demyelination and subsequent additional demyelination and impaired remyelination, in the ON of patients with a first episode of optic neuritis. In the early phase of optic neuritis, MT MRI is more sensitive than atrophy measurements in detecting disease-related changes.
Subject(s)
Magnetic Resonance Imaging , Optic Neuritis/pathology , Acute Disease , Adult , Atrophy , Disease Progression , Evoked Potentials, Visual , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Optic Neuritis/physiopathology , Sensitivity and SpecificityABSTRACT
The aim of the present study was to apply diffusion tensor MRI (DT-MRI), a quantitative MRI measure which reflects tissue organization, to dementia with Lewy bodies (DLB). DT-MRI scans were obtained from 15 patients with probable DLB and 10 sex- and age-matched healthy controls. Abnormalities were found in the corpus callosum, pericallosal areas and the frontal, parietal, occipital and, less prominently, temporal white matter of patients compared with controls. Abnormalities were also found in the caudate nucleus and the putamen. The average grey matter volume was lower in patients than in controls. These findings of concomitant grey matter atrophy and white matter abnormalities (as detected by DT-MRI) in regions with a high prevalence of long connecting fibre tracts might suggest the presence of neurodegeneration involving associative cortices. The modest involvement of the temporal lobe fits with the relative preservation of global neuropsychological measures and memory tasks in the early stage of DLB. The selective involvement of parietal, frontal and occipital lobes might explain some of the clinical and neuropsychological features of DLB, providing a possible distinctive marker for this disease. The abnormalities found in the subcortical grey matter may indicate that DLB and Parkinson's disease share a similar nigrostriatal involvement caused by common pathophysiological mechanisms.
