[1] Univ Texas Hlth Sci Ctr Houston, McGovern Med Sch, Dept Neurol, Div Multiple Sclerosis & Neuroimmunol, 6431 Fannin St,MSB 7-222, Houston, TX 77030 USA
[2] Univ Texas Hlth Sci Ctr Houston, McGovern Med Sch, Dept Neurol, Div Multiple Sclerosis & Neuroimmunol, Houston, TX USA
[3] Baylor Coll Med, Maxine Mesinger Multiple Sclerosis Comprehens Care, Dept Neurol, Houston, TX USA
[4] Inova, Fairfax, VA USA