Recent advancements in micro-optics have allowed scientists to observe the cells of the deep brain and capture momentary snapshots of microscopic changes occurring over months and years with aging or illness. But a new method devised by Stanford researchers offers the potential of monitoring tiny branches of neurons in a live brain for months at a time.
A recent story in Stanford Report describes the new method and how it may improve our understanding of both the normal biology and diseased states of this hidden tissue:
With the new method, "Imaging is possible over a very long time without damaging the region of interest," said Juergen Jung, operations manager of the Schnitzer lab. Tiny glass tubes, about half the width of a grain of rice, are carefully placed in the deep brain of an anaesthetized mouse. Once the tubes are in place, the brain is not exposed to the outside environment, thus preventing infection. When researchers want to examine the cells and their interactions at this site, they insert a tiny optical instrument called a microendoscope inside the glass guide tube. The guide tubes have glass windows at the ends through which scientists can examine the interior of the brain. . . .
The guide tubes allow researchers to return to exactly the same location of the deep brain repeatedly over weeks or months. While techniques like MRI scans could examine the deep brain, "they couldn't look at individual cells on a microscopic scale," said [Mark Schnitzer, PhD, associate professor of biology and of applied physics.] Now, the delicate branches of neurons can be monitored during prolonged experiments.
The researchers' findings (subscription required) were published this week in Nature Medicine.