Background: We hypothesized that right and left temporal lobe epilepsy (RTLE and LTLE, respectively) have distinctive spatial patterns of white matter (WM) changes that can be differentiated and interpreted with the use of multiple diffusion parameters. We compared the global microstructure of fiber bundles with regard to WM alterations in both RTLE and LTLE, addressing some of the methodological issues of previous studies. Methods: Diffusion tensor imaging data from 17 patients with RTLE (age: 40.7 ± 10.4), 15 patients with LTLE (age: 37.3 ± 10.4), and 15 controls (age: 34.8 ± 11.2) were used in the study. WM integrity was quantified by fractional anisotropy (FA), mean diffusivity (MD), longitudinal diffusivity (LD), and radial diffusivity (RD). The diffusion parameters were compared between the groups in tracts representing the core of the fiber bundles. The volumes of hippocampi and amygdala were subsequently compared across the groups, while the data were adjusted for the effect of hippocampal sclerosis. Results: Significantly reduced FA and increased MD, LD, and RD were found bilaterally over widespread brain regions in RTLE. An increase in MD and RD values was observed in widespread WM fiber bundles ipsilaterally in LTLE, largely overlapping with regions where FA was lower, while no increase in LD was observed. We also found a difference between the LTLE and RTLE groups for the right hippocampal volume (with and without adjustment for HS), whereas no significant volume differences were found between patients and controls. Conclusions: It appears that patients with RTLE exhibit a more widespread pattern of WM alterations that extend far beyond the temporal lobe in both ipsilateral and contralateral hemisphere; furthermore, these changes seem to reflect more severe damage related to chronic degeneration. Conversely, more restrained changes in the LTLE may imply a pattern of less severe axonal damage, more restricted to ipsilateral hemisphere. Comprehensive finding of more prominent hippocampal atrophy in the RTLE raises an interesting issue of seizure-induced implications on gray matter and WM microstructure that may not necessarily mean a straightforward causal relationship. Further correlations of diffusion-derived metrics with neuropsychological and functional imaging measures may provide complementary information on underlying WM abnormalities with regard to functional hemispheric specialization.
- Publikační typ
- časopisecké články MeSH
Neuromyelitis optica spectrum disorders (NMOSD) are demyelinating, autoimmune diseases affecting the central nervous system. Typically, recurrent optic neuritis and longitudinal extensive transverse myelitis dominates the clinical picture. In most cases NMOSD are associated with autoantibodies targeting the water channel aquaporin-4 (AQP-4). NMOSD usually present in young adults. Clinical findings suggestive of NMOSD in elderly patients should raise the suspicion of a paraneoplastic etiology. To our knowledge, we report the first case of a 66 year-old female patient with paraneoplastic NMOSD that is associated with squamous cell lung carcinoma. Anti-AQP-4 was present in both the serum and cerebrospinal fluid of the patient. However, immunhistological staining of the malignant tissue did not show presence of AQP-4 on the surface of tumour cells.
- MeSH
- akvaporin 4 imunologie MeSH
- autoprotilátky analýza krev MeSH
- imunohistochemie MeSH
- kouření MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- nádory plic komplikace MeSH
- neuromyelitis optica komplikace diagnostické zobrazování terapie MeSH
- paraneoplastická polyneuropatie diagnostické zobrazování etiologie terapie MeSH
- páteř diagnostické zobrazování MeSH
- senioři MeSH
- spinocelulární karcinom komplikace MeSH
- Check Tag
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- přehledy MeSH
The pathomechanism of cluster headache (CH) is not entirely understood, but central and peripheral components were suggested. A recent report showed that transcranial magnetic stimulation measured cortical excitability was increased in the hemisphere ipsilalteral to the pain. In the current study we set out to investigate the amplitude of resting brain fMRI activity to find signatures of the increased excitability. High resolution T1 weighted and resting state functional MRI images were acquired from seventeen patients with CH in pain free period and from twenty-six healthy volunteers. Patients' data were normalized (e.g. inverted along the midsagittal axis) according to the headache side. Independent component analysis and a modified dual regression approach were used to reveal the differences between the resting state networks. Furthermore, the timecourses were decomposed into five frequency bands by discrete wavelet decomposition and were also re-regressed to the original data to reveal frequency specific resting activity maps. Two of the identified resting state networks showed alterations in CH. When the data were inverted to have patients' headaches on the left, the ipsilateral attention network showed increased connectivity in 0.08-0.04 Hz frequency band in the in CH group. In the same dataset, cerebellar network showed higher functional connectivity in 0.02-0.01 Hz range in the ipsilateral cerebellum. When the data of patients having headache on the left were inverted to the right, similar increased signal was found in the ipsilateral attention network in 0.08-0.04 Hz band. The cerebellar network showed increased connectivity in the cerebellum in 0.02-0.01 Hz band in patients. The Fourier analysis of these area revealed increased power in CH at all cases. Our results showed alterations of brain functional networks in CH. The alterations of resting state activity were found in the hemisphere ipsilateral to the pain, signifying the altered cortical processing in the pathomechanism of CH.
- MeSH
- cluster headache patofyziologie MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie MeSH
- mapování mozku MeSH
- mozek patofyziologie MeSH
- nervová síť patofyziologie MeSH
- odpočinek fyziologie MeSH
- transkraniální magnetická stimulace MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: Alzheimer's disease (AD) and normal pressure hydrocephalus (NPH) are both associated with cognitive decline and ventriculomegaly. While promising approach in differentiating between the two diseases, only a few diffusion tensor imaging (DTI) studies compared directly NPH and AD patients. The current study compares global whitematter (WM) alterations in AD and NPH addressing some of the methodological issues of previous studies. PATIENTS AND METHODS: Diffusion tensor images were obtained from 17 patients with NPH, 14 with AD, and 17 healthy controls. White matter integrity was quantified by fractional anisotropy (FA), mean (MD), axial (λ1) and radial diffusivity (RD). The diffusion parameters were compared between the groups in 'skeletonised' tracts representing the core of the fibre bundles. RESULTS: Reduced FA was found in NPH patients throughout the corpus callosum, particularly in the splenium, along with increased RD. On the other hand, FA, MD and RD were higher in NPH in the cortico-fugal fibres arising from the frontal and parietal cortex. While no FA changes were detected in AD patients compared to controls, widespread increased RD was observed. When comparing NPH and AD patients, higher FA, MD and RD was observed in the corona radiata in the periventricular fibres arising from the frontal and parietal cortex in NPH patients. The ventricular volumes were correlated with diffusivity parameters in the tracts next to the ventricles in AD and NPH patients. CONCLUSION: Our analysis identified a pattern of WM diffusion alterations that can differentiate NPH patients from controls and AD patients.
- MeSH
- Alzheimerova nemoc diagnóza patologie MeSH
- anizotropie MeSH
- bílá hmota patologie MeSH
- diferenciální diagnóza * MeSH
- lidé středního věku MeSH
- lidé MeSH
- normotenzní hydrocefalus diagnóza patologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- zobrazování difuzních tenzorů metody MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH