Non-invasive Detection of Persistent Cortical Hypoxia in Multiple Sclerosis Using Frequency Domain Near-Infrared Spectroscopy (fdNIRS).

There may be a relationship between hypoxia and inflammation, which is important in the outcomes of a wide array of human diseases. Multiple sclerosis (MS) is one such disease. There is evidence that hypoxia may influence inflammation in MS. We showed previously that about 40% of participants with MS had hypoxia in the cortical grey matter using frequency-domain near-infrared spectroscopy (fdNIRS). In this study, we aimed to determine if hypoxia in MS persists chronically (for a year or more) by measuring at baseline and ≥12 months later. We found that hypoxia persists for at least a year in 80% of participants with MS. As more individuals remained hypoxic than returned to normoxia, the development of hypoxia may relate to disease progression.