[Sonography of the small and large intestine--differential diagnosis of wall thickening].

With the aid of a subtle examination technique using suitable ultrasonic equipment, it is possible to visualize small and large bowel wall changes. In a prospective study, 416 patients with small-bowel or large-bowel diseases, and 197 patients with no diseases affecting the intestinal tract were investigated. It was found that the wall thickness--as reflected in the thickness of the echo-poor outer ring - in the healthy bowel may measure up to 3 mm. A thickness of 4-5 mm must be considered borderline. A wall thickness of 6 mm or more is one of a number of morphological changes that signal intestinal disease. In 78.4% of the cases, the pathological finding was correctly described or correctly evaluated with respect to its biological significance with the aid of ultrasound. An accurate determination of the anatomical localization was possible in 92.3% of these cases. The ultrasonographic appearance of the various bowel diseases is not infrequently similar or even identical. Nevertheless, the detection of a pathological finding always makes it possible to narrow down the differential diagnosis. Ultrasonography is a suitable procedure for the detection and follow-up of intestinal wall thickening, which represents an important patho-morphological substrate of a number of intestinal diseases. Within the framework of small and large bowel diagnostic evaluation, it should be used alongside endoscopy and X-ray contrast examination. Ultrasound is not able to exclude possible bowel disease.