Comparison of Pentax HiLine and Olympus Lucera systems at screening colonoscopy

AIM:To compare the performance characteristics of Pentax HiLine(PHL)(with i-scan) and Olympus Lucera(OL) systems in a screening population.METHODS:Screening colonoscopies in asymptomatic guaiac faecal occult blood test-positive patients with PHL(n = 58) and OL(n = 425) colonoscopes were analysed.All procedures were performed by a single colonoscopist.PHL used white-light endoscopy(WLE) on scope insertion and contrast/surface enhancement(i-scan 1) on withdrawal,and OL utilised WLE both on insertion and withdrawal.Patient age,sex,instrument insertion and withdrawal times,nurse assessed patient comfort scores,midazolam and fentanyl doses,procedure completion and rates of lesion detection were recorded separately for each group.Comparisons between the groups were made using either Fisher’s exact test(for dichotomous variables) or Mann-Whitney U test(for ordinal and continuous variables).RESULTS:Colonoscopy completion rates were similar in both groups:413/425(97.2%) for OL and 55/58(94.9%) for PHL(P = 0.24).For complete colonoscopies,the two groups were well matched for age,sex,colonoscope insertion times(mean 11.1 min in OL vs 11.6 min in PHL,P = 0.93) and normal colonoscopy withdrawal times(mean 15.6 min in OL vs 14.7 min in PHL,P = 0.2).Patients in the PHL group experienced a small increase in discomfort(mean patient comfort scores were 0.49 in the OL and 0.95 in the PHL group,P < 0.0001).While Fentanyl doses required were similar between groups(mean 57.5 μg in OL vs 61.4 μg in PHL,P = 0.13),slightly more Midazolam was required in the PHL group(mean 2.1 mg in OL vs 2.4 mg in PHL,P = 0.035).There was no difference in polyp(58% in OL vs 67% in PHL) or adenoma(49% in OL vs 56% in PHL) detection rates between the groups.Neither the total number of polyps and adenomas,nor the characteristics of these(including size,location or presence of advanced features) were different between the two systems.CONCLUSION:This study suggests that there is no advantage of either colonoscope system in lesion detection.