The development of a split in the retina, usually caused by degeneration.
A tear is more common in people with severe myopia.
A retinal tear may also be caused by a severe eye injury.
Retinal detachment usually follows a retinal tear.
If a retinal tear is found before there is any detachment, the hole is sealed by laser treatment or cryopexy (application of extreme cold).
Blockage of an artery supplying blood to the retina, most commonly due to thrombosis or embolism, The disorder can result in permanent blindness or loss of part of the field of vision, depending on the artery affected and whether or not the condition can be treated quickly enough.... retinal artery occlusion
(ARN) severe inflammation and necrosis of the retina associated with inflammation and blockage of retinal blood vessels, haemorrhage and death of retinal tissue, and retinal detachment. It may affect both eyes (bilateral acute retinal necrosis, BARN), and visual prognosis is poor. ARN is thought to be due to viral infection.... acute retinal necrosis
(perineal trauma) an injury to the perineum, which may be sustained during childbirth. Perineal tears can be classified by degree. First-degree tears involve the perineal skin and vaginal mucosa only. Second-degree tears involve the perineal muscles but not the anal sphincter. Third-degree tears involve the anal sphincter complex: the external anal sphincter (EAS) and internal anal sphincter (IAS). These are subclassified as 3a (less than 50% of EAS thickness torn), 3b (more than 50% of EAS thickness torn), and 3c (IAS torn). Fourth-degree tears involve the anal sphincter complex (EAS and IAS) and the anal epithelium or rectal mucosa. It is vitally important that these injuries are recognized and repaired by competent personnel. See also obstetric anal sphincter injury.... perineal tear
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