Developmental Anatomy and Anomalies of the Gastrointestinal Tract with Involvement in Major Malformative Syndromes

Abstract

A clear understanding of normal gastrointestinal development is essential for the understanding of the diseases of the gastrointestinal tract. The following account of the embryology of the human gastrointestinal tract is largely based upon descriptions by numerous authors of staged human embryos in the Carnegie Embryological Collection. Many of these appear in Contributions to Embryology published by the Carnegie Institution of Washington (1915–1966). Of special interest is the series Developmental Horizons in Human Embryos by Streeter (1942, 1945, 1948, 1951) and Heuser and Corner (1957). O’Rahilly (1973) continued and amplified Streeter’s “Horizons” and renamed them “Stages.” These are now known as the “Carnegie Stages.” O’Rahilly and Muller (1987) have supplemented and revised the “Stages,” contributed extensively to the literature of human embryology based on the staged embryos of the Carnegie Collection, and published the third edition of their text (O’Rahilly and Muller 2001). Some of their work was utilized extensively in the preparation of this chapter. Classical texts and atlases of descriptive human embryology also used include those of Wilhelm His (1885), Franz Keibel and Franklin P. Mall (1912), Thomas S. Cullen (1916), Erich Blechschmidt (1961, 1963, 1973), Raymond F. Gasser (1975, 2002), Jan J. Jirasek (1983, 2001, 2004), Kalousek et al. (1990), Marjorie A. England (1996), and Gerd Steding (2009). Modern studies have added ultrastructural, histochemical, immunohistochemical, and other important details, but with few exceptions, the descriptive embryology of the human gastrointestinal tract established a century ago remains unchanged.