In vivo vital staining as an aid to identification of esophagogastric mucosal junction in man

A method is described for accurate, rapid and safe differential staining of squamous and columnar cells in the esophagus. In all 10 patients studied during elective esophagoscopy, instillation of Lugol's solution into the distal esophagus stained the squamous epithelium a gray-black. Columnar epithelium and areas of inflammation remained unstained. A sharp circumferential line at the squamocolumnar junction was obtained in patients with a normal esophagus; this line was irregular in patients with esophagitis. The procedure does not interfere with further histologic staining for permanent slides. Lugol's solution reacts with glycogen in squamous cells, as demonstrated by the PAS and PAS-diastase methods. Under these conditions the effect of Lugol's solution on thyroid function studies other than protein-bound iodine is minimal and of short duration. This staining procedure has significant clinical and research potential because it allows the endoscopist to locate, rapidly and accurately, the squamocolumnar junction, its relationship to other anatomic or pathologic entities and the extent as well as the proximal borders of esophagitis.