Duodenal contraction wave patterns in patients with and without ulcer.

To determine whether differences in frequency of specific wave sequences and types existed in the four parts of the duodenum in ulcer subjects and controls an analysis of contraction waves in 14 controls and 10 duodenal ulcer patients of similar age was done by a statistical analysis of differences between the two groups. A water-perfused tube system was used. Differences in motor activity, namely, decreased frequency of waves in the proximal duodenum and increased frequency of waves in the distal duodenum in ulcer subjects as compared to controls was demonstrated. This involved a statistically significant decrease in numbers of mixing (or basic rhythm) waves in the proximal duodenum. Increased numbers of isolated waves were found in ulcer patients in the distal duodenum. The predominant types of contraction waves in both ulcer and control subjects were isolated and simultaneous waves, with peristaltic waves were less common in the fasting state. These findings suggest that differences exist in the types of contraction waves in duodenal ulcer subjects compared to controls.