Corneal blindness in Plato's cave: the acting forces to prevent and revert corneal opacity. Part I: epidemiology and new physiopathological concepts.

The burden of corneal blindness and visual deficiency can be felt worldwide. Its association with several endemic diseases such as childhood blindness, trauma, infectious keratitis (including variants caused by herpes, hanseniasis, and fungi), vitamin A deficiency, diabetes mellitus, and other dry eye syndromes reflects its poorly understood underlying mechanisms and suggests that the actual frequency of the disease is underestimated. The low effectiveness of preventive and therapeutic strategies against corneal scarring or deformity predicts a high frequency of patients with corneal blindness in the future. Corneal blindness is associated with environmental factors and socioeconomic limitations that restrain health assistance and maintain a modest efficiency of the current therapeutic strategies for resolving corneal diseases in large-scale programs. We present here a critical review of the concepts associated with corneal blindness that need to be considered when planning strategies to prevent and treat corneal blindness worldwide (to be able to leave Plato's cave, where corneal blindness is encaged.

Blindness in leprosy patients of Kaduna State, Northern Nigeria.

We examined the eyes of 311 leprosy patients to determine the prevalence of blindness and impaired vision, and the causes of blindness in leprosy patients in Northern Nigeria. There was impaired vision or blindness in 74 eyes. Both eyes were affected in 5.1% of patients while 2.9% were totally blind. Leprosy alone was responsible for total blindness in 1.3% of patients, while other ocular diseases contributed to blindness in 1.6%. Exposure keratitis (21.3%), corneal opacities (13.5%) and chronic uveitis (10.1%) were the commonest leprotic cause of blindness. Primary care and early intervention could help prevent blindness in many of these patients. Primary eye care should therefore be given a prominent position in the training of carers of leprosy patients.