Optical coherence tomography, a new technology, gauges the thickness of retinal nerve fiber, which becomes the optic nerve and is affected early in the course of MS. This is also the only part of the brain where nerve cells, even in healthy people, are not coated in myelin. The OCT test would specifically pick up on nerve damage, as opposed to more general brain changes, the researchers said.
"This allows you to measure the thickness of the axon itself," O'Looney explained.
The cost of the eye exam is only a fraction (10 percent to 15 percent) of a conventional MRI and, O'Looney noted, "it's user-friendly, it's inexpensive and it's less time-consuming for the patient."
For the study, the Hopkins researchers used the eye exam to scan
the layers of nerve fibers of the
There appeared to be a strong association between retinal fiber thickness and how much the brain had atrophied.
But optical nerve damage could be used to indicate of other
ailments, usually
Calabresi's team is now doing further studies involving the technology. If those studies pan out, OCT could be a way to deliver effective treatments to patients much earlier, he said.
"The longer MS goes undiagnosed the more damage is done," Calabresi stated. "Having a better test is extremely helpful."
The technology could end up paving the way for more effective drugs as well.
"As we move forward in developing new drugs to protect the axon from damage, we need a way to measure that. And OCT is certainly a strong potential technology that could be used," O'Looney said.
More information
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