RELATIONSHIP BETWEEN ESOPHAGEAL ATRESIA WITH TRACHEOESOPHAGEAL FISTULA AND VERTEBRAL ANOMALIES IN MAMMALIAN EMBRYOS

Background/Purpose: The association of esophageal atresia with tracheo esophageal fistula and vertebral anomalies is well known, although the embryology of the combined defects has not yet been analysed. The pre sent study describes the origin and development of esophageal atresia with tracheoesophageal fistula and vertebral anomalies in embryos usin g a rat model of VATER association produced by Adriamycin administrati on. Results: The lung buds were seen to develop from the laryngotrache al groove but the trachea failed to grow normally and the foregut over growth compensated for this failure. The trachea developed by tracheal ization of the foregut, which continued as a fistula to the lower esop hageal segment. The notochord did not separate from the foregut at the correct time (before day 11 in rat embryos, Carnegie stage 11 in huma n embryos). Overgrowth of the foregut ventrally and caudally carried w ith it the attached notochord in the same direction leading to abnorma l bending of this structure. Conclusion: This irregularity of the noto chord may be responsible for abnormal development of the vertebrae. Co pyright (C) 1998 by W.B. Saunders Company.