The incidence and reliability of individual radiographic signs in the small intestine in crohn's disease

Abstract

Films from barium follow-through examination of 50 cases of Crohn's disease, 25 cases of various malabsorption syndromes and 25 cases of unexplained diarrhoea (as controls) were reviewed independently by two radiologists. The agreed incidence and observer variation in interpreting radiological signs was studied. Examination of commonly accepted signs of Crohn's disease showed that contraction and rigidity were the most reliable. Cobblestone mucosa, longitudinal streaks of barium in the wall, and ulceration (marked mucosal irregularity and clefts) were occasionally reported in controls or cases of malabsorption. When the cases of Crohn's disease were considered on their own the most frequent and reliable signs were contraction, rigidity, clefts and marked surface irregularity. These all had an incidence of more than 25 per cent with an observer variation of less than half the agreed incidence. Cobblestone mucosa and stenosis also occurred frequently but showed frequent observer variation. Skip lesions, featureless mucosa, slight surface irregularity, longitudinal streaks in the wall and fistulae ococcurred infrequently and had an incidence of observer disagreement that was usually more than twice the agreed incidence. Stippling or flocculation of barium occurred in 40 per cent of cases of Crohn's disease, but was less frequent and less severe than in the malabsorption syndrome. With careful technique the terminal ileum could be demonstrated in 70 per cent-of cases of Crohn's disease. Assessment of mucosal fold thickness and separation in duodenum and jejunum showed that the cases of Crohn's disease of the ileum were similar to controls and differed from patients with malabsorption. Jejunal loop width in these patients with Crohn's disease was intermediate between the width found in the other two groups.