资源预览内容
亲,该文档总共2页全部预览完了,如果喜欢就下载吧!
资源描述
VOA常速英语听力2012年09月合辑(文本):Glaucoma-A-Stealth-Disease-And-Major-Cause-of-BlindnessGlaucoma is a major cause of blindness around the world, but especially in developing countries. The World Health Organization says glaucoma is a greater public health challenge than cataracts, because the blindness caused by glaucoma is permanent.If you think you are not at risk for glaucoma, think again. Glaucoma is a disease that steals the sight of people around the world - and they typically dont even know they have the disease until it has permanently destroyed at least 40 percent of their vision.Dr. Alan Robin specializes in treating glaucoma.Its the leading cause of blindness in the United States. In Hispanics and in African-Americans, its the second leading cause of blindness, said Robin.In China and in India, glaucoma is the second leading cause of blindness.The glaucoma you see in sub-Saharan Africa is a much more aggressive, much more blinding disease than the glaucoma we see in Americans or even African-Americans in the United States, he said.Dr. Eric Fleischer sees these racial differences at Medstar Washington Hospital Center.Pretty much anybody who has ancestry in Africa has an increased chance for developing glaucoma, said Fleischer.Age is another risk factor for glaucoma, although people of all ages can get it. As Dr. Robin explains, its a group of diseases that commonly produce pressure in the eye.An eye is sort of like a watch. And behind the face of the watch that has the numbers, fluid is made. It goes through your pupil and into the front of the watch between the numbers or the face and the crystal. Theres an area around the edge of the watch that drains the fluid, he said.When that drain is clogged, the fluid cant leave the eye as fast as it is produced. The rising pressure within the eye damages and eventually kills the optic nerve. The result is blindness.The process is usually so painless and subtle, people dont notice it.Typically theyll notice if they bump into door frames, because theyve lost their peripheral vision, or theyll start having car accidents because they dont see a car to one side or the other, said Fleischer.Fortunately, glaucoma can be easily diagnosed. The simplest test measures peripheral vision. Thats because with glaucoma the side vision is the first to go.The good news is that, if caught early, glaucoma can be managed.Its not preventable, but its treatable, said Robin.Glaucoma is not reversible, but, as researchers learn more about it, they grow more hopeful that glaucoma can one day be cured or even prevented.- 2 -
网站客服QQ:2055934822
金锄头文库版权所有
经营许可证:蜀ICP备13022795号 | 川公网安备 51140202000112号