Abstract
It is well-known that in the Western countries left sided diverticular disease is common whereas in Japan right sided diverticular disease is more frequent. Pressure study of the sigmoid colon together with histologic observations have clarified the pathogenesis of left sided diverticular disease, however no answer has been given as to the pathogenesis of right sided diverticular disease. We measured intraluminal pressure of the ascending colon with catheter-tip transducer (Mikro-Tip transducer) by using colonoscope (Figure 1a, 1b). Ten patients with right sided diverticular disease and 7 nomal controls were examined. At resting state the mean colonic motility index of the diseased segments was greater than that of controls but the difference was not statistically significant (Table 4, Figure 7). After intravenous injection of neostigmin methylsulfate higher pressure waves were more frequently observed in the diseased segments than in the ascending colon of controls and the mean colonic motility index was five times greater than that of controls (Table 5, Figure 7). Histologic examinations of surgical specimens of 15 patients with right sided diverticular disease revealed that all 48 diverticula were pseud-dverticula protruding through the circular muscle (Figure 10). Radiografies of operative specimens useing intraarterial barium injection showed an arterial branch arched over the dome of the diverticulum (Figure 11). These investigations were the same as the results of studies on left sided diverticular disease in the Western countries. We conclude that the abnormality of motility and the high intraluminal pressure in the ascending colon seemed to play an important role in the pathogenesis of right sided diverticular disease.
