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Abstract

I greatly appreciate Dr. Lee's comments regarding my article studying single-balloon colonoscopy for prior incomplete standard colonoscopy.1Keswani R.N. Single-balloon colonoscopy versus repeat standard colonoscopy for previous incomplete colonoscopy: a randomized, controlled trial.Gastrointest Endosc. 2011; 73: 507-512Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar I concur that his group's efforts in studying cap-assisted colonoscopy as a low-cost rescue method for incomplete colonoscopy should be recognized. However, I do think there are important differences in reported efficacy between the two modalities that should be emphasized.In the cited uncontrolled study, cap-assisted colonoscopy was used immediately in patients with difficult colonoscopy (comprising 16.7% of the patients undergoing colonoscopy), with a success rate of 94%.2Lee Y.T. Hui A.J. Wong V.W. et al.Improved colonoscopy success rate with a distally attached mucosectomy cap.Endoscopy. 2006; 38: 739-742Crossref PubMed Scopus (64) Google Scholar However, this subset of patients is not equivalent to patients with prior incomplete colonoscopy (such as in my study using single-balloon colonoscopy), making comparisons of efficacy inappropriate. In a subsequent, randomized study comparing cecal intubation rates of standard colonoscopy and cap-assisted colonoscopy, patients with incomplete procedures were crossed-over to the alternative endoscopic modality.3Lee Y.T. Lai L.H. Hui A.J. et al.Efficacy of cap-assisted colonoscopy in comparison with regular colonoscopy: a randomized controlled trial.Am J Gastroenterol. 2009; 104: 41-46Crossref PubMed Scopus (106) Google Scholar In the subgroup of 27 patients with an unsuccessful initial standard colonoscopy, subsequent cap-assisted colonoscopy successfully achieved cecal intubation in 66.7% of patients. This cecal intubation rate of 66.7% likely reflects the true success rate of cap-assisted colonoscopy in patients with prior incomplete standard colonoscopy and is notably lower than that of the majority of studies using single-balloon and double-balloon enteroscopy for the same indication, including my study. Thus, although cap-assisted colonoscopy may be a reasonable immediate rescue option for difficult colonoscopy, patients referred for prior incomplete colonoscopy may require the use of alternative endoscopic tools such as balloon colonoscopy to achieve a success rate closer to 100%. Therefore, these endoscopic modalities should be available at repeat exam. I greatly appreciate Dr. Lee's comments regarding my article studying single-balloon colonoscopy for prior incomplete standard colonoscopy.1Keswani R.N. Single-balloon colonoscopy versus repeat standard colonoscopy for previous incomplete colonoscopy: a randomized, controlled trial.Gastrointest Endosc. 2011; 73: 507-512Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar I concur that his group's efforts in studying cap-assisted colonoscopy as a low-cost rescue method for incomplete colonoscopy should be recognized. However, I do think there are important differences in reported efficacy between the two modalities that should be emphasized. In the cited uncontrolled study, cap-assisted colonoscopy was used immediately in patients with difficult colonoscopy (comprising 16.7% of the patients undergoing colonoscopy), with a success rate of 94%.2Lee Y.T. Hui A.J. Wong V.W. et al.Improved colonoscopy success rate with a distally attached mucosectomy cap.Endoscopy. 2006; 38: 739-742Crossref PubMed Scopus (64) Google Scholar However, this subset of patients is not equivalent to patients with prior incomplete colonoscopy (such as in my study using single-balloon colonoscopy), making comparisons of efficacy inappropriate. In a subsequent, randomized study comparing cecal intubation rates of standard colonoscopy and cap-assisted colonoscopy, patients with incomplete procedures were crossed-over to the alternative endoscopic modality.3Lee Y.T. Lai L.H. Hui A.J. et al.Efficacy of cap-assisted colonoscopy in comparison with regular colonoscopy: a randomized controlled trial.Am J Gastroenterol. 2009; 104: 41-46Crossref PubMed Scopus (106) Google Scholar In the subgroup of 27 patients with an unsuccessful initial standard colonoscopy, subsequent cap-assisted colonoscopy successfully achieved cecal intubation in 66.7% of patients. This cecal intubation rate of 66.7% likely reflects the true success rate of cap-assisted colonoscopy in patients with prior incomplete standard colonoscopy and is notably lower than that of the majority of studies using single-balloon and double-balloon enteroscopy for the same indication, including my study. Thus, although cap-assisted colonoscopy may be a reasonable immediate rescue option for difficult colonoscopy, patients referred for prior incomplete colonoscopy may require the use of alternative endoscopic tools such as balloon colonoscopy to achieve a success rate closer to 100%. Therefore, these endoscopic modalities should be available at repeat exam. Spending less for rescuing a failed colonoscopyGastrointestinal EndoscopyVol. 74Issue 2PreviewI read with interest the two recent articles by Schembre et al1 and Keswani2 on how to tackle the problem of a failed regular colonoscopy procedure. Schembre et al used spiral enteroscopy as a rescue method and achieved a 92% cecal intubation rate in 24 patients. In a randomized, controlled trial of 30 patients with prior unsuccessful regular colonoscopy procedures, Keswani demonstrated that single-balloon enteroscopy was superior to repeating regular colonoscopy in achieving a higher cecal intubation rate (92.9% in single-balloon enteroscopy vs 50% in regular colonoscopy group). Full-Text PDF