Global data on blindness
Globally, it is estimated that there are 38 million persons who are blind. Moreover, a further 110 million people have low vision and are at great risk of becoming blind. The main causes of blindness and low vision are cataract, trachoma, glaucoma, onchocerciasis, and xerophthalmia; however, insufficient data on blindness from causes such as diabetic retinopathy and age-related macular degeneration preclude specific estimations of their global prevalence. 
Refractive error blindness
Recent data suggest that a large number of people are blind in different parts of the world due to high refractive error because they are not using appropriate refractive correction. Refractive error as a cause of blindness has been recognized only recently with the increasing use of presenting visual acuity for defining blindness. In addition to blindness due to naturally occurring high refractive error, inadequate refractive correction of aphakia after cataract surgery is also a significant cause of blindness in developing countries. 
Change blindness: past, present, and future
Change blindness is the striking failure to see large changes that normally would be noticed easily. Over the past decade this phenomenon has greatly contributed to our understanding of attention, perception, and even consciousness. 
Sudden Bilateral Blindness Following Massive Uterine Bleeding: Reports of 2 Cases
Background: Most cases of sudden blindness are due to vascular causes. Ischemic optic neuropathy is a rare cause of blindness reported most commonly in association with collagen-vascular diseases, infectious processes, and systemic hypotension related to massive exsanguinating hemorrhage. 
Multiple Myeloma Relapse Presenting as Unilateral Blindness
Multiple Myeloma is a chronic disease. While therapy is largely focused for control, relapse is inevitable. Central nervous system relapse of myeloma is less common. Unilateral painless blindness is a rare entity and its occurrence in the setting of multiple myeloma has not been commonly reported. We encountered a case of multiple myeloma on treatment, who developed unilateral blindness and later on confirmed to have relapse of disease. 
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