High-concentration Small-volume Versus Low-concentration Large-volume Iodine Solution for Esophageal Chromoendoscopy

1% Lugol iodine solution was sprayed from the esophagogastric junction towards a location approximately 20 cm away from the upper incisors in the cervical esophagus.

Before chromoendoscopy, a 20 ml syringe was employed to draw 3 ml of 5% iodine stock solution and 17 ml air. When staining, the iodine was quickly expelled through the endoscope's working channel at 20 cm of the esophagus from the incisor. An iodine mist was created because of the rapid spurt of the iodine solution and air, which prompts even distribution of the iodine solution on the esophageal wall. The lower segments of the esophageal wall were stained with the remaining iodine solution in the working channel by repeatedly spraying the air/iodine mixture using the syringe, resulting in consistent and uniform staining for the whole esophagus.