NEFL and multiple sclerosis: A number of studies have identified that neurofilament light chains are increased in the CSF in the majority of patients with relapsing, remitting multiple sclerosis.[60–62] There is some preliminary evidence that neurofilament heavy chain levels may be raised in the CSF in patients with optic neuritis or multiple sclerosis, and that such levels may be a predictor of the presence of enhancing lesions on MRI as well as elevated levels of MBP in the CSF.