imaging

Non-invasive MEG scan can predict cognitive therapy outcomes in MS

A non-invasive scan that measures network activity across the brain was able to predict the outcomes of behavioral therapies designed to improve cognitive function in people with multiple sclerosis (MS), a study demonstrates. Brain network function, as assessed by the test, called magnetoencephalography (MEG), “could play an important role…

Imaging Brain Metabolites May Help Diagnose, Monitor MS

A new imaging technique called magnetic resonance spectroscopic imaging, or MRSI, could be useful for diagnosing and monitoring multiple sclerosis (MS), according to a small study. “If confirmed in longitudinal clinical studies, this new neuroimaging technique could become a standard imaging tool for initial diagnosis, for disease progression and…

Gray Matter in Hippocampus Can Help Distinguish Between Two MS Types

Subtle changes in structure in the hippocampus — a region of the brain involved in processing memories — can differentiate between relapsing-remitting and primary progressive multiple sclerosis, according to a new study. The study, “Unraveling the MRI-Based Microstructural Signatures Behind Primary Progressive and Relapsing–Remitting Multiple Sclerosis Phenotypes,”…

Myelin Loss Can Be Assessed With Innovative Imaging Approach, Study Suggests

A novel imaging approach enables assessment of key nervous system deterioration in multiple sclerosis (MS), a new study in mice suggests. The research, “Development of a PET radioligand for potassium channels to image CNS demyelination,” was published in the journal Scientific Reports. MS is characterized by damage to myelin (a process called demyelination), which is an insulating sheath around axons (the long projections of neurons) that enables effective neuronal communication. As a result, patients experience a variety of symptoms, including muscle stiffness and weakness, fatigue and pain. Although existing MS medications suppress immune responses and reduce flare-ups, none can cure the disease. Despite the importance of demyelination in MS, scientists and clinicians do not currently have a way to directly image myelin damage. Magnetic resonance imaging (MRI) is used, but it does not enable the distinction between demyelination and inflammation, which are common in patients with MS. Upon myelin damage, voltage-gated potassium channels (cellular membrane proteins) become exposed. As a result, cells leak potassium, which impairs proper neuronal communication. This prompted researchers to develop a tracer that targets potassium channels. "In healthy myelinated neurons, potassium channels are usually buried underneath the myelin sheath," Brian Popko, PhD, the study’s senior author, said in a press release. Popko is a professor of neurological disorders and director of the Center for Peripheral Neuropathy at The University of Chicago. Exposed potassium channels can be targeted by the MS medication 4-aminopyridine (4-AP; dalfampridine), which partially repairs nerve conduction and mitigates MS symptoms. Using mouse models of MS, the researchers demonstrated that 4-AP binding to potassium channels is greater in demyelinated axons in comparison with well-myelinated axons. The greater binding of 4-AP led to its accumulation in damaged axons. Then, the team evaluated several fluorine-containing derivatives of 4-AP, and found that the most effective in binding to potassium channels was 3-fluoro-4-aminopyridine (3F4AP), which can be labeled with radioactive 18F. This labeling enables detection of demyelinated regions with a novel strategy based in positron emission tomography (PET). "3F4AP is the first tracer whose signal increases with demyelination, potentially solving some of the problems of its predecessors," said Pedro Brugarolas, PhD, first author of the study. Existing PET tracers bind to myelin. This translates to decreases in signal in the presence of myelin loss, “which can be problematic for imaging small lesions” Brugarolas noted. Importantly, the findings in mice were confirmed in monkeys. Experiments showed that the radiolabeled 3F4AP enters the primate brain and accumulates in areas with less myelin. Collectively, “these data indicate that [18F]3-F-4-AP may be a valuable PET tracer for detecting [central nervous system] demyelination noninvasively,” the team wrote. "We think that this PET approach can provide complementary information to MRI which can help us follow MS lesions over time," Popko said. The novel PET strategy enables the evaluation of therapies to repair myelination and also could help assess how much myelin loss is involved in other neurological disorders, such as traumatic brain injury and spinal cord injury, but also in diseases not commonly linked to demyelination, "such as brain ischemia, psychiatric disorders, and neurodegenerative diseases, including Alzheimer's," Popko concluded.

Philips Unveils In-Progress Radiology Portal for Diagnosing, Treating Neurological Diseases

Royal Philips recently announced the introduction of the IntelliSpace Portal 9.0, the latest edition of its advanced comprehensive visual analysis and quantification platform for neurological disorders. The platform was presented at the 2016 Radiological Society of North America Annual Meeting (RSNA), taking place through Dec. 2 in Chicago. Currently a work in…

NIH Researcher Working on MS Imaging Wins 2016 Barancik Prize for Innovation

Dr. Daniel Reich, a researcher with the National Institutes of Health (NIH),  has been recognized for his pioneering work on brain imaging to advance both the treatment of people with multiple sclerosis (MS) and scientific understanding of the disease. Reich, a neurologist, neuro-radiologist and neuroscientist, was awarded the 2016 Barancik Prize for Innovation in MS…

#ECTRIMS2016 – Eye Imaging Tools May Help Predict 5- or 10-Year MS Disability

Two presentations at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) 2016 Congress, now underway in London, underscored the value of measures of neurodegeneration in the eye in predicting a patient’s future disability. Peter Calabresi with the Johns Hopkins School of Medicine opened the session with the presentation, “Tools for…