Open Access
CC BY 4.0 · Journal of Digestive Endoscopy 2025; 16(02): 113-115
DOI: 10.1055/s-0045-1809616
News and Views

Optimizing Bowel Preparation in Small Bowel Capsule Endoscopy: It's All About Timing

Vaneet Jearth
1   Department of Gastroenterology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
,
Kshitiz Dogra
2   All India Institute of Medical Sciences, New Delhi, India
› Author Affiliations
 

Abstract

Small bowel capsule endoscopy (SBCE) allows for radiation-free and noninvasive visualization of small bowel (SB) mucosa with high-quality images and is critical in the management of a variety of conditions, including suspected SB bleeding, suspected or definitive SB Crohn's disease, SB tumors including intestinal polyposis syndromes, and, to a lesser extent, celiac disease. The optimal preparation protocol remains a subject of considerable debate, with no universally accepted bowel cleansing regimen identified to achieve the desired performance measure. In this news and views, we discuss a recently published multicenter, prospective, single-blinded (for investigators) randomized controlled trial in patients for whom SBCE was performed for suspected SB bleeding to ascertain the optimal timing and preparation for SBCE.


Since its inception in 2000, small bowel capsule endoscopy (SBCE) has evolved into an important tool in clinical practice, ushering in a new paradigm in gastrointestinal endoscopy, particularly small bowel (SB), which was previously thought to be inaccessible to endoscopists.[1] [2] SBCE allows for radiation-free and noninvasive visualization of SB mucosa with high-quality images and is critical in the management of a variety of conditions, including suspected SB bleeding, suspected or definitive SB Crohn's disease, SB tumors including intestinal polyposis syndromes, enteropathy/enteritis caused by a variety of factors, including nonsteroidal anti-inflammatory drugs, and, to a lesser extent, celiac disease. Detection rates vary by indication but range between 56 and 61% in a pooled analysis. The technique exhibits an excellent safety profile; however, it has notable miss rates of 5.9% for vascular lesions, 0.5% for ulcers, and 18.9% for neoplasms.[3] [4] This can be ascribed to human error due to the huge quantity of pictures requiring extensive interpretation times or insufficient vision of SB mucosa due to residual intestinal contents.[1] [2] [3] The most recent European Society of Gastrointestinal Endoscopy update has identified adequate or good bowel preparation as a critical performance metric for SBCE.[5] Nonetheless, the optimal preparation protocol remains a subject of considerable debate, with no universally accepted bowel cleansing regimen identified to achieve the desired performance measure.[5] [6] [7]

A recent prospective multicenter randomized trial (PrepRICE trial) aimed to address this debate by assessing the optimal timing and preparation for SBCE utilizing a low-dose polyethylene glycol (PEG) plus ascorbic acid regimen.[8] Only adult patients with suspected SB bleed, characterized by overt or occult bleeding of unknown origin that persists or recurs following negative bidirectional endoscopic procedures, were included. Patients with a suspected or confirmed diagnosis of Crohn's disease or polyposis syndrome were excluded. This study analyzes four groups employing distinct preparation protocols. Two involve taking the purgative completely before swallowing the capsule, whereas the other two involve drinking the bowel preparation after the capsule has entered the duodenum. Patients were randomly assigned to one of four groups: group 1 (G1) received 1 L of purgative (PEG + ascorbic acid) the night prior to the procedure, G2 received 1 L in the morning up to 2 hours prior to capsule ingestion, G3 received 0.5 L of purgative in the morning up to 2 hours prior to SBCE + 0.5 L of solution after the capsule reached the duodenum, and G4 received 1 L after the capsule reached the duodenum. The clinicians in charge of patient management and SBCE assessment were not aware of the purgative regimen. In addition, all patients received 100 mg simethicone 20 minutes before ingesting SBCE. The objectives were delineated as follows: (1) to compare the quality of visualization of the entire and distal SB (SBVQ) across four distinct preparation protocols, (2) to evaluate the diagnostic yield (DY) among these four preparation protocols, and (3) to assess patient-reported outcomes regarding symptoms and satisfaction with the preparation regimen. SBVQ was evaluated using the quantitative index established by Brotz et al,[9] while DY was defined as the proportion of patients exhibiting at least one lesion with high bleeding potential (P2, Saurin classification[10]). For tercile estimation, SB transit time (SBTT) was divided by 3.

A total of 387 patients were included, with 99 in group 1 and 96 in each of the remaining three groups. The cohort comprised 59% females, with a median age of 73 years (interquartile range, 23). The completion rate of the examination was lower in G1 (90%, p < 0.001). Patients who received purgative during SBCE had reduced SBTTs (G3 and G4, p = 0.001). Globally and per terciles, SBVQ was statistically superior in patients receiving intraprocedural purgatives, with rates of adequate visualization of 91 and 93% (G3 and G4, respectively) compared with 65 and 75% (G1 and G2). The SBVQ showed no significant differences across the capsule models employed (p > 0.05). No significant differences were observed in DY (overall and per terciles) when comparing the four preparation protocols (p > 0.05). However, the overall DY of patients receiving intraprocedural purgatives (G3 + G4) was higher (42.7 vs. 31.3%, p = 0.02); significant differences were detected in the second and third terciles. Similarly, G3 and G4 exhibited a higher rate of angioectasia detection (p = 0.04). Patients' satisfaction was markedly higher for G4 (median, 4 points; interquartile range, 1).

Commentary

Suspected SB bleeding is the most common indication for SBCE, which is recommended as the first-line investigation prior to considering other endoscopic and radiological diagnostic tests.[5] [8] As a result, the PrepRICE trial only included individuals with a suspected SB bleed in this study. The downstream implications of inadequate mucosal visualization during SBCE are substantial, as it results in a reduction in diagnostic accuracy, which in turn increases the likelihood of rebleeding, repetition of SBCE or alternative procedures, and an increase in costs.[1] [2] [3] Although the use of intestinal purgatives before to SBCE is currently advised by experts,[11] various meta-analyses have yielded inconsistent results regarding their effectiveness in improving DY.[12] [13] [14] While there is growing understanding of the relevance of timing of bowel preparation in improving procedure quality, data for intraprocedural preparation remains sparse.[8] A recent study reported noninferiority of the 1 L PEG plus ascorbate solution over the standard 2 L PEG for SBCE preparation.[15]

The PrepRICE trial employed 1 L of PEG combined with sodium ascorbate to compare four distinct laxative protocols. The authors deserve commendation for conducting a well-designed randomized trial with an adequate sample size and for employing validated scores to report SB findings and grade SBVQ, thereby enhancing intra- and interobserver reliability. Furthermore, patient-reported outcomes were assessed.

Globally and per terciles, the authors report superior SBVQ with intraprocedural purgatives. Unlike most previous studies, superior SBVQ translated into better DY with intraprocedural regimens as compared with preprocedural regimens, with the former displaying considerably higher DY in the second (18% vs. 11%) and third (17% vs. 8%) terciles. Due to the frequent localization of pathology and the increased likelihood of residual intestinal contents obstructing visibility in distal SB, it is important to emphasize the superior performance of intraprocedural regimens even in the latter. Additionally, overall satisfaction was higher for intraprocedural regimens, especially in the group that consumed the entire PEG solution after the capsule reached the SB (G4).

The essential question is whether this study has settled the debate over the optimum bowel preparation regimen for SBCE, or whether the jury is still out. This trial endorses the “The later the better” approach to bowel preparation for SBCE, as it demonstrates the clear superiority of intraprocedural regimens in terms of most endpoints in patients with suspected SB bleed. However, additional information is required to generalize this approach to other indications of SBCE and to determine the optimal choice of purgatives. It will also be interesting to evaluate the impacts of metoclopramide, which was employed in this study based on capsule stomach retention time, but data on which was not provided across different protocols, which may have an impact on SBTT. Furthermore, central reading of images would have strengthened the evidence by minimizing interobserver variation in reporting, a method that can be utilized in future trials.

In conclusion, timing of bowel preparation is critical for optimizing performance measures in SBCE, at least in patients with suspected SB bleed. It is anticipated that forthcoming societal guidelines will provide a more definitive framework for standardized bowel preparation, informed by recent evidence. This will promote more uniform reporting of procedure-related and patient-reported outcomes in the advancing field of capsule endoscopy.



No conflict of interest has been declared by the author(s).

  • References

  • 1 Pennazio M, Rondonotti E, Pellicano R, Cortegoso Valdivia P. Small bowel capsule endoscopy: where do we stand after 20 years of clinical use?. Minerva Gastroenterol (Torino) 2021; 67 (01) 101-108
  • 2 Ghoshal UC, Roy A, Goenka MK. Capsule endoscopy for small bowel bleed: current update. Indian J Gastroenterol 2024; 43 (05) 896-904
  • 3 Pecere S, Chiappetta MF, Del Vecchio LE. et al. The evolving role of small-bowel capsule endoscopy. Best Pract Res Clin Gastroenterol 2023; 64-65: 101857
  • 4 Viazis N, Papaxoinis K, Vlachogiannakos J, Efthymiou A, Theodoropoulos I, Karamanolis DG. Is there a role for second-look capsule endoscopy in patients with obscure GI bleeding after a nondiagnostic first test?. Gastrointest Endosc 2009; 69 (04) 850-856
  • 5 Sidhu R, Shiha MG, Carretero C. et al; External Voting Panel. Performance measures for small-bowel endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative - update 2025. Endoscopy 2025; 57 (04) 366-389
  • 6 Enns RA, Hookey L, Armstrong D. et al. Clinical practice guidelines for the use of video capsule endoscopy. Gastroenterology 2017; 152 (03) 497-514
  • 7 Yung DE, Rondonotti E, Sykes C, Pennazio M, Plevris JN, Koulaouzidis A. Systematic review and meta-analysis: is bowel preparation still necessary in small bowel capsule endoscopy?. Expert Rev Gastroenterol Hepatol 2017; 11 (10) 979-993
  • 8 Estevinho MM, Sarmento Costa M, Franco R. et al. Preparation Regimens to Improve Capsule Endoscopy Visualization and Diagnostic Yield (PrepRICE): a multicenter randomized trial. Gastrointest Endosc 2025; 101 (04) 856-865.e3
  • 9 Brotz C, Nandi N, Conn M. et al. A validation study of 3 grading systems to evaluate small-bowel cleansing for wireless capsule endoscopy: a quantitative index, a qualitative evaluation, and an overall adequacy assessment. Gastrointest Endosc 2009; 69 (02) 262-270 , 270.e1
  • 10 Silva JC, Pinho R, Ponte A. et al. Predicting the risk of rebleeding after capsule endoscopy in obscure gastrointestinal bleeding - external validation of the RHEMITT Score. Dig Dis 2020;
  • 11 Melson J, Trikudanathan G, Abu Dayyeh BK. et al. Video capsule endoscopy. Gastrointest Endosc 2021; 93 (04) 784-796
  • 12 Kotwal VS, Attar BM, Gupta S, Agarwal R. Should bowel preparation, antifoaming agents, or prokinetics be used before video capsule endoscopy? A systematic review and meta-analysis. Eur J Gastroenterol Hepatol 2014; 26 (02) 137-145
  • 13 Triantafyllou K, Gkolfakis P, Dimitriadis GD. Abandon purgative bowel preparation before small-bowel capsule endoscopy? Not yet. Gastrointest Endosc 2017; 85 (03) 684
  • 14 Marmo C, Riccioni ME, Pennazio M, Antonelli G, Spada C, Costamagna G. Small bowel cleansing for capsule endoscopy, systematic review and meta- analysis: timing is the real issue. Dig Liver Dis 2023; 55 (04) 454-463
  • 15 Caccia R, Rimondi A, Elli L. et al. Bowel preparation for small bowel capsule endoscopy: standard regimen with 2 L polyethylene glycol versus 1 L polyethylene glycol plus ascorbate. Clin Endosc 2025; 58 (02) 285-290

Address for correspondence

Vaneet Jearth, MD, DM, MRCP
Department of Gastroenterology, Post Graduate Institute of Medical Education and Research
Chandigarh 160012
India   

Publication History

Article published online:
12 June 2025

© 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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  • References

  • 1 Pennazio M, Rondonotti E, Pellicano R, Cortegoso Valdivia P. Small bowel capsule endoscopy: where do we stand after 20 years of clinical use?. Minerva Gastroenterol (Torino) 2021; 67 (01) 101-108
  • 2 Ghoshal UC, Roy A, Goenka MK. Capsule endoscopy for small bowel bleed: current update. Indian J Gastroenterol 2024; 43 (05) 896-904
  • 3 Pecere S, Chiappetta MF, Del Vecchio LE. et al. The evolving role of small-bowel capsule endoscopy. Best Pract Res Clin Gastroenterol 2023; 64-65: 101857
  • 4 Viazis N, Papaxoinis K, Vlachogiannakos J, Efthymiou A, Theodoropoulos I, Karamanolis DG. Is there a role for second-look capsule endoscopy in patients with obscure GI bleeding after a nondiagnostic first test?. Gastrointest Endosc 2009; 69 (04) 850-856
  • 5 Sidhu R, Shiha MG, Carretero C. et al; External Voting Panel. Performance measures for small-bowel endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative - update 2025. Endoscopy 2025; 57 (04) 366-389
  • 6 Enns RA, Hookey L, Armstrong D. et al. Clinical practice guidelines for the use of video capsule endoscopy. Gastroenterology 2017; 152 (03) 497-514
  • 7 Yung DE, Rondonotti E, Sykes C, Pennazio M, Plevris JN, Koulaouzidis A. Systematic review and meta-analysis: is bowel preparation still necessary in small bowel capsule endoscopy?. Expert Rev Gastroenterol Hepatol 2017; 11 (10) 979-993
  • 8 Estevinho MM, Sarmento Costa M, Franco R. et al. Preparation Regimens to Improve Capsule Endoscopy Visualization and Diagnostic Yield (PrepRICE): a multicenter randomized trial. Gastrointest Endosc 2025; 101 (04) 856-865.e3
  • 9 Brotz C, Nandi N, Conn M. et al. A validation study of 3 grading systems to evaluate small-bowel cleansing for wireless capsule endoscopy: a quantitative index, a qualitative evaluation, and an overall adequacy assessment. Gastrointest Endosc 2009; 69 (02) 262-270 , 270.e1
  • 10 Silva JC, Pinho R, Ponte A. et al. Predicting the risk of rebleeding after capsule endoscopy in obscure gastrointestinal bleeding - external validation of the RHEMITT Score. Dig Dis 2020;
  • 11 Melson J, Trikudanathan G, Abu Dayyeh BK. et al. Video capsule endoscopy. Gastrointest Endosc 2021; 93 (04) 784-796
  • 12 Kotwal VS, Attar BM, Gupta S, Agarwal R. Should bowel preparation, antifoaming agents, or prokinetics be used before video capsule endoscopy? A systematic review and meta-analysis. Eur J Gastroenterol Hepatol 2014; 26 (02) 137-145
  • 13 Triantafyllou K, Gkolfakis P, Dimitriadis GD. Abandon purgative bowel preparation before small-bowel capsule endoscopy? Not yet. Gastrointest Endosc 2017; 85 (03) 684
  • 14 Marmo C, Riccioni ME, Pennazio M, Antonelli G, Spada C, Costamagna G. Small bowel cleansing for capsule endoscopy, systematic review and meta- analysis: timing is the real issue. Dig Liver Dis 2023; 55 (04) 454-463
  • 15 Caccia R, Rimondi A, Elli L. et al. Bowel preparation for small bowel capsule endoscopy: standard regimen with 2 L polyethylene glycol versus 1 L polyethylene glycol plus ascorbate. Clin Endosc 2025; 58 (02) 285-290