esophagus endoscopy procedure

endoscope endoscopy pain esophagus cancer esophageal carcinoma surgery treatment vector body oesophagus regurgitation digestive gastrointestinal gastric dysphagia oesophageal stage anatomical tumor achalasia manometry diagram obstruction exam medical inflammation reflux digestion anatomy gerd gastroscopy system health disease human cell medicine gastroesophageal organ esophago gastrectomy oncology illustration diagnosis illness mouth