When MRI can do what PET can…

One of the advantages of positron emission tomography is its ability to probe the molecular aspects of brain function. Of course PET is quite invasive: your brain is injected with radioactive material.

Now MRI is going molecular without the radioactive burden.

Money quote from the press release:

In this report, Harvard researchers describe how they link a relatively common MRI probe (superparamagnetic iron oxide nanoparticles) to a short DNA sequence that binds to proteins in cells responsible for brain tissue repair (glia and astrocytes). Then, researchers used the eye drops on mice with conditions that cause “leaks” in the blood-brain barrier. When the animals’ brains were scanned using MRI, brain repair activity was visible. Glia and astrocytes help repair brain and nerve tissue, and have a role in numerous diseases and disorders that cause at least microscopic breaches in the blood-brain barrier, including traumatic brain injury, multiple sclerosis, stroke, cardiac arrest, and glioma, among others. Furthermore, the researchers believe that the probes may also help diagnose thinning of vascular walls in brains, which occurs as Alzheimer’s disease progresses.