The long and short of flexible sigmoidoscopy: does it matter?

Physicians performing fiberoptic sigmoidoscopy may choose between a 35 and 60 cm instrument. Confusion and dispute exist concerning the advantages of one over the other. In an effort to resolve this question, 100 consecutive symptomatic patients were examined in an outpatient sigmoidoscopy clinic. Both the Olympus OSF-30 and Olympus OSF-60 flexible sigmoidoscopes were used on each patient alternately. Mean examination time, patient tolerance, diagnostic findings, instrument cost, physician training time, and insertion length were recorded and compared. The longer scope detected five more polyps and 25 additional cases of diverticulosis which were located beyond the reach of the shorter scope. The increased number of findings with the longer scope was expected; however, the increased number of polyps was not statistically significant. The additional number of findings with the longer scope was expected and with increased number of examinations the increased number of polyps may prove to be statistically significant. Neither instrument can substitute for colonoscopy in the overall management of colorectal neoplasms. We conclude that with adequate training and cost control, either instrument can be used for screening proctosigmoidoscopy; but the trend suggests a greater number of polyps are detected with the longer instrument.