Cap-assisted water immersion colonoscopy – a prospective, randomized trial

Authors: P. Falt 1;  V. Šmajstrla 1;  P. Fojtík 1;  M. Liberda 1;  M. Kliment 1;  J. Tvrdík 2;  O. Urban 1,3
Authors‘ workplace: Centrum péče o zažívací trakt, Vítkovická nemocnice, Ostrava 1;  Přírodovědecká fakulta, Ostravská univerzita v Ostravě 2;  Lékařská fakulta, Ostravská univerzita v Ostravě 3
Published in: Gastroent Hepatol 2013; 67(2): 118-123
Category: Digestive Endoscopy: Original Article


Water immersion insertion can reduce discomfort and need for sedation during colonoscopy. A cap attached to the colonoscope tip may improve insertion during air insufflation colonoscopy. According to several reports, both techniques used independently may result in higher detection of neoplastic lesions. Our study was designed to evaluate the efficacy of cap-assisted water immersion compared to water immersion colonoscopy in minimally sedated patients.

A total of 208 patients meeting the inclusion criteria were randomized to either the cap-assisted water immersion (Cap Water) or the water immersion colonoscopy (Water). The primary endpoint was cecal intubation time.

The cecal intubation time was 6.9 ± 2.9 minutes in Cap Water and 7.4 ± 4.2 minutes in Water arm (p = 0.73). The success rate of minimal sedation colonoscopy was equal in both groups (92.9%; p = 1.00). There were non-significant trends toward lower discomfort (p = 0.06), less need for abdominal compression (p = 0.06) and lower difficulty score from the endoscopist's point of view (p = 0.05) during the Cap Water colonoscopy. The adenoma detection rate was similar in both arms (44% in Cap Water vs 45% in Water group; p = 0.88). There were no complications recorded in the study.

In comparison with water immersion without cap, the cap-assisted water immersion colonoscopy was not able to shorten the cecal intubation time. However, it has some potential to reduce patient discomfort and difficulty of colonoscope insertion. Potential impact on improved detection of neoplastic lesions has to be evaluated by further studies.

Key words:
cap – colonoscopy – colorectal cancer – water immersion


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