esophagogastroduodenoscopy medical procedure

enteroscopy stomach gastroenterologist endoscopy esophagus intestine bowel small endoscopic gastric muscle procedure oral treatment achalasia minimally vector gastroscopy invasive disorder mucosa submucosa endoscope esophageal les tunnel nonsurgical sphincter fibers stricture anatomical junction digestive system illustration graphic poster therapy gastroesophageal disease surgery organ internal air balloon gut nutrition microbiota biology biopsy