Journal of neuroimaging : official journal of the American Society of Neuroimaging
-
The authors' aim was to evaluate the time course of the basal vein's (BVR) mean flow velocity (VBVR) in patients after traumatic brain injury and its relation to intracranial pressure (ICP), cerebral perfusion pressure (CPP), and the clinical outcome. ⋯ Repetitive Doppler examination of the basal cerebral veins may add new aspects to the monitoring of head-injured patients.
-
Although conventional magnetic resonance imaging (cMRI) is widely used for diagnosing multiple sclerosis (MS) and monitoring disease activity and evolution, the correlation between cMRI and clinical findings is far from strict. Among the reasons for this "clinical-MRI paradox," a major role has been attributed to the limited specificity of cMRI to the heterogeneous pathological substrates of MS and to its inability to quantify the extent of damage in the normal-appearing tissue. Modern quantitative MRI techniques have the potential to overcome some of the limitations of cMRI. ⋯ Magnetic resonance spectroscopy can add information on the biochemical nature of such changes, with the potential to improve significantly our ability to monitor inflammatory demyelination and axonal injury. Finally, functional MRI might provide new insights into the role of cortical adaptive changes in limiting the clinical consequences of white-matter structural damage. This review outlines the major contributions given by MRI-based techniques to the diagnostic work-up of MS patients, to the understanding of the pathobiology of the disease, and to the assessment of the effects of new experimental treatments.
-
Several studies have demonstrated that brain atrophy can be detected over relatively short intervals from the earliest stages of multiple sclerosis (MS). Reviewing the published data, the authors highlight some hypothetical pathological mechanisms proposed as determinants of brain atrophy. ⋯ Examination of the pathological mechanisms proposed in the reviewed studies led the authors to believe that inflammation is only in part responsible for the development of brain atrophy. This conclusion may have an implication for the strategies of tissue protection advocated in the early stages of the RR course and strengthen recent evidence indicating that anti-inflammatory immunomodulatory agents and immunosuppressive treatments, which predominantly act against the inflammatory component of disease activity, may not have similar effects on progressive tissue loss, either in RR or progressive MS.
-
Involvement of the brain is one of the most important complications of Behçet's disease, but its diagnosis is difficult because of the lack of effective imaging tools. Therefore, technetium-99m ethyl cysteinate dimer (Tc-99m ECD) single-photon emission computed tomography (SPECT) of the brain was used to detect abnormal regional cerebral blood flow in patients with neuro-Behçet's syndrome (NBS). ⋯ The parietal lobes were the most common areas with hypoperfusion lesions. Tc-99m ECD brain SPECT is a more sensitive and useful tool than brain MRI for detecting hypoperfusion areas of the brain in NBS patients.
-
Case Reports
Diffusion magnetic resonance imaging in intermediate form of maple syrup urine disease.
An 8-year-old boy with the intermediate variant of maple syrup urine disease is reported. On b = 1000 s/mm2 (heavily diffusion weighted) images of diffusion magnetic resonance imaging, there was symmetric high signal in the globus pallidus, mesencephalon, dorsal pons, and nucleus dentatus, consistent with restriction of the mobility of water molecules. Apparent diffusion coefficient (ADC) maps revealed low ADC values ranging from 0.42 to 0.56 x 10(-3) mm2/s in these regions, compared to those of apparently unaffected regions in the brain parenchyma ranging from 0.63 to 0.97 x 10(-3) mm2/s. It is suggested that the areas of increased signal (and low ADC values) are the result of dysmyelination as a reflection of disorganized tissue integrity.