VI J. R. VON RONNEN PREFACE This atlas is a selection of the roentgenograms of patients who visited the Radiology Department at the University Hospital in Leiden between 1970 and 1974. The heads of this department are Prof. J. R. von Ronnen and Prof. A. E. van Voorthuisen. In this atlas, the most frequently occurring radiological abnormalities of the small intestine are illustrated as clearly as possible - without the shadows caused by flocculation...