Imaging areas around the brain may offer hints about prognosis on patients diagnosed with multiple sclerosis (MS), researchers reported at MS Virtual 2020, the joint meeting of the Americas Committee for Treatment and Research in Multiple Sclerosis and the European Committee for Treatment and Research in Multiple Sclerosis.
Leptomeningeal inflammation in MS can be putatively identified by leptomeningeal contrast enhancement on gadolinium-enhanced 3D T2-fluid attenuated inversion recovery (FLAIR) magnetic resonance (MR) images, the study authors noted in the background for the abstract.
In the longitudinal retrospective study, they wanted to determine if certain imaging patterns were associated with clinical, demographic, and MRI parameters in MS patients.
They assessed 217 MS patients—193 with relapsing-remitting MS, 24 with progressive MS—at baseline and over 18 months follow-up using 3T 3D FLAIR pre- and post-contrast and subtraction images.
The investigators measured differences in three areas: leptomenoingeal contrast enhancement, dura matter enhancement, and meningeal vessel wall enhancement.
"Dura matter enhancement was the most frequent meningeal enhancement pattern," Franziska Hildesheim, MSc, a research fellow at the Buffalo Neuroimaging Analysis Center in New York, told Neurology Today At the Meetings. "It was found in approximately 50 percent of patients, and its correlation to T1/T2 lesions and deep gray matter volume underlines its relevance as an imaging marker in patients with MS."
In other imaging results, 24 percent of MS patients had leptomeningeal contrast enhancement, and 47 percent revealed dura matter enhancement with inclusive falx cerebri; 24 percent of patients showed wall vessel enhancement.
Hildesheim said the presence of leptomeningeal contrast enhancement correlated with age and higher ventricular cerebrospinal fluid volume. Thirty-eight percent were positive for leptomeningeal contrast enhancement and showed additional wall vessel enhancement, compared with 20 percent of subjects who were negative for leptomeningeal contrast enhancement (p=0.055).
Hildesheim said dura matter enhancement was associated with higher T1/T2 lesion load, higher ventricular cerebrospinal fluid volume, and decreased total deep gray matter and hippocampus volumes. All three meningeal enhancement patterns showed a high persistence in shape and size at follow-up, she said.
She also noted that "leptomeningeal contrast enhancement assessed by MRI has been associated with rapid progression of disease in patients with MS. But dura mater enhancement and meningeal vessel wall enhancement are two other typical patterns of meningeal inflammation, which are less well investigated."
"Our data show that in vivo 3T imaging of leptomeningeal contrast enhancement, dura matter enhancement, and meningeal vessel wall enhancement can help to further discriminate subsets of patients with MS with gray matter pathology," she said. "Both dura matter enhancement and meningeal vessel wall enhancement closely match recent descriptions of lymphatic vessels visualized by FLAIR MR imaging."
"In MS, drainage of debris and immune cell trafficking towards the dural lymphatics is possibly increased as a result of inflammation," Hildesheim continued. "Through MS imaging of dural matter enhancement and meningeal vessel wall enhancement sites, a malfunctioning lymphatic waste drainage system in multiple sclerosis might possibly be uncovered."
Commenting on the study, Jack P. Antel, MD, FAAN, professor of neurology and neurosurgery at McGill University in Montreal, Canada, said the imaging study is an important area of study. But he said the use of these imaging markers are not yet ready for prime time.
"If you look at the pathology in MS, you see the loss of the myelin under the surface, but if you look at every other neurologic condition where you see lots of inflammation over the surface of the brain such as among people with lymphomas or with chronic meningitis, you simply don't see that myelin loss," he said.
"So we ask: Why is this happening in MS? What is specific about what is going on over the surface of the brain that is contributing to this distinct pathology in MS?" Dr. Antel said. "One of the big take home messages from this kind of work is that these imaging technologies have the potential to translate these biological concepts into reality and to clinical outcomes."
Hildesheim and Dr. Antel disclosed no relevant relationships with industry.
Link Up for Related Information:
MS Virtual 2020 Abstract PS07.05: Hildesheim F, Ramasamy D, Berglsand D, et al. Leptomeningeal, dura mater and meningeal vessel wall enhancements in multiple sclerosis.
Harrison DM, Wang KY, Fiol J, et al. Leptomeningeal enhancement at 7T in multiple sclerosis: frequency, morphology, and relationship to cortical volume. J Neuroimaging 2017;27(5):461-468.