Imaging Studies in Dyspepsia Arnold Berstad, Trygve Hausken, Odd Helge Gilja, Aasve Nesland and Svein Ødegaard From the Department of Medicine, Division of Gastroenterology, Haukeland University Hospital, Bergen, Norway Eur J Surg 1998; Suppl 582: 42–49 ABSTRACT Patients with functional dyspepsia have discomfort centred in the upper abdomen in the absence of oesophagitis, ulcer, cancer or other pathology which could have explained the dyspepsia. It is generally accepted that neither endoscopy, nor other imaging modalities give any positive findings supporting the diagnosis. However, recent investigations have shown that both endoscopic and ultrasonographic imaging show changes: erosive prepyloric changes (EPC) and accommodation abnormalities, respectively, in a high percentage of the patients. The diagnostic sensitivity and specificity of the changes are not yet known, but the fact that they are also seen in several other conditions characterised by dyspepsia, for instance in gallstone disease, may simply indicate that they are linked to epigastric discomfort in general, and not to a specific dyspeptic condition. Ultrasonographic imaging is a non-invasive, widely available, convenient, and reliable method for evaluation of gastric emptying, gastric motility, transpyloric flow and accommodation disturbances, which may play a crucial role in the pathogenesis of dyspepsia. Key words: gastric accommodation, gastric erosions, functional dyspepsia, ultrasonography. INTRODUCTION A large proportion of patients undergoing upper gastrointestinal endoscopy have discomfort centred in the upper abdomen in the absence of oesophagitis, ulcer, cancer or other pathology which could have explained their dyspepsia. Many of these cases are classified as functional dyspepsia. The gastroscopy is described as “negative” even though it may reveal minor mucosal abnormalities, like “erosive prepyloric changes” (EPC)(45). These prepyloric fold formations with red spots, streaks or frank erosions on top of the folds are not due to Helicobacter pylori (4), intake of NSAIDs or other exogenous or endogenous irritating substances. They seem rather to be a manifestation of stress (46). The changes do not explain the dyspepsia, but are associated with it, and may delineate a purer subgroup of patients with stress-induced, functional dyspepsia. Other stomach abnormalities, like an abnormal postcibal configuration, may be due to an impairment of the proximal stomach to accommodate a meal. The latter, which is easily studied by ultrasonography, is also regularly present in patients with functional dyspepsia. Thus various imaging modalities, i.e. endo- scopy and ultrasonography, may reveal changes in dyspepsia patients. These changes have hitherto largely been neglected, and their diagnostic sensitivity and specificity are not yet clearly established. We believe, however, that they may provide important clues to the understanding of the pathogenesis of epigastric dis- comfort in general. In the following, we will focus on EPC and gastric accommodation as imaged by endo- scopy and ultrasonography, respectively, and show how they both may relate to the same functional abnormalities in patients with dyspepsia. WHERE DOES THE PAIN COME FROM? It is well established that there is a weak relationship between dyspepsia and both endoscopic and histologi- cal findings in the gastric mucosa (34). The role of gastric motor disturbances in dyspepsia is also a subject of dispute. At least one third of the patients with functional dyspepsia have delayed gastric emptying of solids on nuclear scintigraphy or abnormal postpran- dial antral motility on manometry. However, the relationship of these abnormalities to symptoms is unclear. Therefore, documentation of delayed empty- ing with nuclear scintigraphic study is of little value in the treatment of these patients (48). Recent investigations suggest that a “stiff ” proximal stomach may account for symptoms in some patients (14). Under normal circumstances, the proximal stomach relaxes in response to both food ingestion and duodenal distension. This vagally mediated reflex allows a controlled, gradual emptying from the body of the stomach to the antrum and duodenum. In some patients, this reflex does not occur properly, resulting in an early filling of the gastric antrum. Recent studies have shown a positive correlation between antral width and the feeling of fullness (21), and, in patients with a 1998 Scandinavian University Press. ISSN 1102–416X Eur J Surg 164 ORIGINAL ARTICLE