Diverticular Disease of the Colon Without Diverticula

Abstract

GEORGE and Leonard (1919) described a peculiar serrated edge on the radiograph of the filled sigmoid colon: sharply pointed close-set serrations resembling the teeth of a saw, which was constantly reproducible. They believed the sign indicated diverticulitis even though no sacs were visible. Case (1929) correlated this description with that of Spriggs and Marxer (1925) who held that it represented a pre-diverticular state. Since then, radiologists have accepted the name prediverticular state as a useful term for the written x-ray report, or, distressed by the lack of an honest pathologic parentage, have ignored it as of no account. The varied pictures which show the condition can be found in review articles of Marcus and Watt (1964, 1965). In contrast to their approach, this paper will consider all patterns with none or at the most a few sacs, which are recognizable as due to diverticular disease because of their frequent occurrence in patients with established diverticulosis in nearby colon, though they may be found in the absence of even a solitary diverticulum. By this definition the findings are common. The radiology of this subject is incomprehensible unless the anatomical asymmetry of the sigmoid and lower descending colon is appreciated. In cross section, this portion of the colon can be thought of as an isosceles triangle, the apex under the mesentery and a taenia at each corner. The lateral wall between the mesenteric and the antimesenteric taeniae is long and flexible, and it is this wall that bends inward to form the anatomical haustral folds and from which the lateral or large diverticula emerge. The short base of the triangle is firmly supported by the antimesenteric taeniae, infolds less obviously, and is the site of emergence of the much smaller antimesenteric diverticula. X-rays traveling in the line of the mesentery will traverse the interhaustral folds and show the lateral sacs on the horizon (Fig. 2) while those traveling at right angles to the mesentery will demonstrate the antimesenteric wall on the horizon, lose the primary sacs against the shadow of the barium-filled lumen, and show the interhaustral folds as bar-shaped half shadows (Fig. 4). This account helps understanding of the anatomy of carefully oriented radiographs in the operative specimen, but in life the view may be an oblique projection, further complicated by the natural curve of the sigmoid colon and by the fact that the radiograph is a picture of the inside of the mucosa and not of the muscle. These points, as well as the crescent shape and alternating nature of the interhaustral folds in diverticular disease, have already been illustrated (Williams, 1963). Methods and Materials The background radiological experience is of routine barium-enema examinations from unspecialized general hospitals.