Comparability of localization data in transnasal and transoral esophagogastroduodenoscopy

BACKGROUND Esophagogastroduodenoscopy is an often-used and safe diagnostic method in gastroenterology. Transnasal esophagogastroduodenoscopy is now an established addition to the endoscopic instrumentarium. Although the two examination methods can be used alongside each other, there is a lack of studies on the comparability of the localization data obtained with the transoral and transnasal methods. METHODS In 135 adult patients presenting for routine outpatient esophagogastroduodenoscopy, transoral esophagogastroduodenoscopy (TOG) was carried out after transnasal esophagogastroduodenoscopy (TNG), and the distance from the naris or incisors, respectively, to the esophagogastric junction was measured. RESULTS The data for 135 patients were analyzed. With the transoral access route, the distance from the upper incisors to the cardia was a mean of 40.5 cm (SD ± 3.4 cm). In the transnasal examinations, the mean distance between the naris and the cardia was 45.6 cm (SD ± 3.5 cm). The correlation analysis showed a very close correlation between the peroral and transnasal data, with a correlation coefficient of r = 0.925. On the basis of the regression line calculated using these data, the formula TNG (cm) = 1.1 × TOG (cm) was developed. Using this formula, localization details obtained with one method can be converted into those for the other method. CONCLUSIONS There is a strong correlation between the localization details obtained with the transnasal and transoral examination methods. The formula for converting localization details from one method to the other, presented here for the first time, is practicable for everyday use and allows rapid conversion.