Just found her blog. It says

" In 2003, I was diagnosed with a rare autoimmune disease called Neuromyelitis Optica (NMO). It is similar to the more widely researched Multiple Sclerosis in that the overactive immune system causes nerve impulses to misfire, often resulting in vision loss and paralysis. While MS tends to affect the brain, however, NMO mainly interrupts the optic nerves and spinal cord. The course of NMO is also more progressive than that of MS; full recoveries from acute attacks are less likely. After several bouts of optic neuritis, the network of nerves connecting my eyes to my brain atrophied, and my vision deteriorated to what the doctors call “counting fingers.” What I see can best be described as shadows and extreme blurriness like I’m eternally walking through a cloud. Or imagine staring into a mirror foggy with steam right after a hot shower–that’s my world."