Purpose: Technical improvements in real-time scanners have revalued the importance of abdominal US for gastrointestinal (GI) tract studies, particularly to investigate chronic inflammatory disease. It is now possible to evaluate intestinal wall thickness accurately, to depict changes in the layers and to study bowel wall motility. Some authors proposed a US classification of Crohn disease into three stages. To investigate the usefulness of this US staging in clinical practice, US findings were compared with the corresponding histologic patterns of the full thickness of the bowel wall.
Material and methods: We examined 58 patients with radiography, endoscopy and US and classified them by Limberg's stage. We compared in vivo and in vitro US findings with the corresponding histologic pattern in seven Crohn patients submitted to ileocolic resection for complications. We performed the US studies with an Acuson 128 XP/10 and 5- or 7-MHz linear probes.
Results and discussion: We found five Crohn 2 and two Crohn 3 cases. In Crohn 2, US showed moderate wall thickening and the presence of all five layers, with corresponding inflammatory infiltration, mainly in the submucosa, at histology. In Crohn 3, US showed marked wall thickening and no layers at all; no layers and wall necrosis areas were found at histology. In Crohn 2, correct drug treatment can stop or reduce intestinal wall lesion progression, which is not possible in Crohn 3 where fistulae and stenoses are likely to develop.
Conclusions: We found the same patterns at abdominal US and histology of the surgical specimens: US accurately showed the characteristics and the extent of bowel wall inflammatory lesions. US is a simple and cost-effective method with no side-effects playing a major role in Crohn disease staging because it permits to study the bowel wall characteristics--an important piece of information for treatment planning.