Introducing SuS, a neurovascular syndrome sometimes confused with MS. Prevalence of SuS is now thought to be higher than previously estimated.

"SuS is a chronic immune-mediated microvascular endotheliopathy that partially or completely occludes the microvasculature in the brain, retina and inner ear, resulting in varying degrees of ischemic injury to these tissues. Clinically, it is characterized by the triad of:

- Encephalopathy (chiefly headaches and cognitive dysfunction, but there can be a variety of other neurologic manifestations)
- Branch retinal artery occlusion (BRAO), as well as vessel wall hyperfluorescence and leakage (Figure 1)
- Hearing loss (often with tinnitus and vertigo) (Figure 2)

This triad is typically accompanied by the distinctive MRI finding of “snowball” lesions in the central portion of the corpus callosum (Figure 3). In its most severe form, SuS threatens to cause dementia, blindness, deafness and severe lifelong physical and mental disability."

An international collaborative study and disease registry are among an array of efforts led out of Cleveland Clinic to better understand and manage this rare autoimmune disease.