Retinopatia diabética

Abstract

Diabetic retinopathy is a frequently observed complication in both type 1 and type 2 diabetes, specially in patients with long term disease and poor glicemic control. Irreversible visual loss appears at the final stages of diabetic retinopathy and it is considered one of the most tragic of diabetic complications. It is also considered an important factor of morbidity and has a high economical impact once it is the leading cause of blindness. The pathophysiology of the retinal microvascular alterations is related to the chronic hyperglycemia that leads to the following circulatory disturbances: loss of vascular tonus, increase in vascular permeability, edema and exudation, with vascular obstruction and ischemia that stimulates neovascularization, which may lead to fibrous retraction and vitreous hemorrhages with retinal detachment. Recent studies have indicated that the strict glicemic and blood pressure controls are effective in reducing or blocking the progression of retinopathy. Up to now no pharmacological agents have shown to be effective in preventing or reducing neovascularization and visual loss. Presently, the most effective available treatment for proliferative retinopathy is laser photocoagulation. Further studies are needed to obtain new products and technologies that could effectively prevent or block retinopathy progression.

Diabetic retinopathy and visual disabilities among patients in a rehabilitation program

“…Diabetes affects nearly every organ in the human body and is a major cause of blindness and lower limb amputation at great economic and social cost to patients and society (15) . The socioeconomic impact of diabetes constitutes a public health problem as its complications reduce productive life of diabetic patients affecting their own and their family's quality of life (4) . Despite widespread awareness campaigns for prevention of diabetes and its complications, diabetes has become an epidemic.…”

“…It is estimated that 7 to 8.0% of the world population have DM. It is thus a serious health problem with significant socioeconomic impact (4) .…”

Eletrorretinograma de campo total em cães diabéticos com catarata

“…Retinopatia diabética (RD) é uma microangiopatia que afeta primariamente as arteríolas pré-capilares, capilares, vênulas pós-capilares e vasos de maior calibre, sendo mais freqüente na do tipo I (40%) do que na do tipo II (20%) (BOSCO et al, 2005).…”

Estudo da síntese de melatonina em retinas de ratos Wistar diabéticos.

“…Na retinopatia diabética ocorrem alterações microvasculares no tecido retiniano como a perda do tônus vascular, alteração do fluxo sangüíneo, aumento da permeabilidade vascular e conseqüentemente extravasamentos e edemas e, por fim, obstrução vascular que leva à neovascularização, com vasos frágeis que se rompem, levando a hemorragias e descolamento da retina (Bosco et al, 2005).…”

“…Entretanto, até o presente momento, o exato mecanismo, ou o conjunto de mecanismos pelos quais a hiperglicemia leva à retinopatia, permanece obscuro (Bosco et al, 2005).…”