News

Summary

• A recently published paper by a collaborative team used advanced Optical Coherence Tomography (OCT) and MRI brain scans of 107 people with MS over four years to track the impacts of MS and to determine whether changes in nerve layers at the back of the eye mirror changes in MRI-detected brain tissue integrity and degeneration.
• The team reported that OCT findings reliably reflected overall brain degeneration, with a specific layer of the retina showing shrinkage at similar rates as specific brain regions seen with MRI. These similar rates of atrophy were more strongly associated in progressive MS for most areas of the brain.
• OCT is a non-invasive, relatively inexpensive and well tolerated imaging method. These findings suggest that OCT findings reflect underlying disease progression, and further validate the usefulness of OCT as an important tool for tracking MS and the impacts in clinical trials.  
• The paper, involving a collaboration of 15 researchers at 6 institutions, was published in the Annals of Neurology in November 2015 (2015;78:801-813).

  Details
Background: MRI scans of the brain have typically been used to help diagnose MS and to observe disease activity and progression in people with MS. Typical clinical MRI scanning detects areas of damage or activity (lesions) in the white matter, areas of the brain that contain myelin-coated nerve fibers. Typical MRI doesn’t have the power to detect or track shrinkage of specific areas of the brain, or lesions that occur in the outer layers of the brain (cortex, gray matter) containing nerve cell bodies. Mounting evidence suggests that damage to nerve cells underlies long-term progressive disability in people with MS. So having easier ways to detect and track nerve degeneration would help speed the search for better therapies.
 
Optical Coherence Tomography (OCT) has been increasingly used as a research tool to detect damage that occurs to the nerves in the back of the eye. OCT is a scan of the nerves in the back of the eye. It is done with a small machine that can fit into an examining room, is relatively inexpensive, painless and well tolerated. Growing evidence has suggested that OCT findings can mirror MS-inflicted damage that occurs in the brain, but it has not been clear how or whether thinning of the nerve at the back of the eye reflects brain shrinkage (atrophy) and nerve degeneration overall or in specific areas of the brain. 
 
The Study: A collaborative team of 15 researchers at six institutions in the U.S. set out to track and compare changes in nerve layers at the back over four years with changes in brain tissue integrity and degeneration. The team conducted high-definition OCT scans twice annually and high-powered (3T) MRI brain scans annually in 107 people with relapsing-remitting, secondary progressive or primary progressive MS.
 
After four years, a comparison of the long-term MRI and OCT results suggested that the rate of tissue thinning seen on OCT reliably mirrored overall brain degeneration, with a specific layer of the retina (“ganglion cell and inner plexiform layer”) showing atrophy at similar rates as specific brain regions (whole brain, gray matter, white matter and the thalamus) seen with MRI. These similar rates of atrophy between OCT and MRI were more strongly associated in progressive MS for most areas of the brain.
 
These findings suggest that OCT findings reflect underlying disease progression, and further validate the usefulness of OCT as an important tool for tracking MS and the impacts in clinical trials.  
 
The paper was published in the Annals of Neurology in November 2015 (2015;78:801-813). The lead author is Dr. Shiv Saidha (Johns Hopkins University). Three members of this team – Drs. Laura Balcer, Peter Calabresi and Elliot Frohman – were the 2015 winners of the Barancik Prize for Innovation in MS Research for their pioneering work related to OCT. Read more