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What is Barrets esophagus involves most commonly which pa of esophagus and explain in detail?
BARRETT'S OESOPHAGUS * It is the metaplastic changes in the mucosa of the oesophagus as the result of GERD. * Squamous epithelium of lower end of the oesophagus is replaced by diseased columnar epithelium (columnar metaplasia). * There is a macroscopically visible length of columnar mucosa with microscopic features of intestinal metaplasia. * It affects lower oesophagus commonly often middle oesophagus also. Ref: SRB&;s manual of surgery,3 rd ed , pg no 728