Whether it is More Appropriate to Spray Lugol's Solution From Cervical Esophagus to Esophagogastric Junction

Whether it is More Appropriate to Spray Lugol's Solution From Cervical Esophagus to Esophagogastric Junction

The aim of this study is to compare the effectiveness and safety of spraying Lugol's solution from cervical esophagus to esophagogastric junction (downward) and from esophagogastric junction to cervical esophagus （upward）during chromoendoscopy.

Chromoendoscopy using Lugol's solution is effective for the detection of early esophageal squamous neoplasia. However, there is no study to investigate the sequence of Lugol's staining during endoscopic procedure.

The aim of this study is to compare the effectiveness and safety of spraying Lugol's solution from cervical esophagus to esophagogastric junction (downward) and from esophagogastric junction to cervical esophagus （upward）during chromoendoscopy.

Inclusion Criteria:

• High risk patients of early esophageal squamous neoplasias.

Exclusion Criteria:

• After esophageal surgery or endoscopic treatment ;
• Known esophageal radiotherapy or chemotherapy ;
• Esophageal stenosis;
• Acute bleeding;
• A known allergy to iodine;
• Coagulopathy (prothrombin time <50% of control, partial thromboplastin time >50 seconds);
• Having food retention;
• Severe hepatic ,renal, cardiovascular or metabolic dysfunction ;
• Being pregnant or lactating.