Capsule endoscopy – not just for the small bowel: a review

Abstract

Video capsule endoscopy is being increasingly used to investigate the esophagus and colon as well as the small bowel. With the advancement of technology used in capsule endoscopy there have been marked improvements in diagnostic rates for colon capsule endoscopy in the detection of colonic polyps and colorectal cancer. It is also being increasingly used in the field if inflammatory bowel disease to investigate for mucosal inflammation and could potentially be used to assess mucosal healing. It also has role in completing the evaluation of colonic pathology in those in whom colonoscopy is incomplete. Esophageal capsule is preferred by patients over esophagogastroduodenoscopy (EGD) but as yet does not rival EGD in terms of diagnostic accuracy however the advent of magnetically steerable capsules may improve this. This review covers advances in the field of colon and esophageal capsule endoscopy; it covers diagnostic capabilities of these 2 tools as well as technical aspects of both procedures and preparation.

Keywords:

• Barrett's oesophagus
• bowel preparation
• colon capsule
• colorectal polyps
• esophageal capsule
• esophageal varices

Financial & competing interests disclosure

C Parker had a previous research post funded by Aquilant. C Spada is a paid consultant for Given Imaging. M McAlindon is supported by Given to attend conferences and has received honoraria from Intromedic Ltd and CapsoVision Ltd for delivering lectures. C Davison has received honoraria in the past as a speaker from Given and Diagmed Healthcare- for past consultancy on national CE nurse training. S Panter is an educational supervisor for Aquilant funded research post as well as being faculty on capsule training course supported by Given imaging and Diagmed. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• PillCam colon capsule endoscopy (CCE) and esophageal capsule endoscopy (ECE) are alternative methods of investigating the colon and esophagus which are both feasible, safe and have benefits in terms of patient preference.

• Preparation is a key requirement of CCE. Current recommendations are to use a split-dosing regimen of a total of 4 l of PEG solution plus low-dose phosphate boosters. This achieves an acceptable level of colonic cleanliness and adequate rates of capsule excretion.

• CCE1 has an inferior sensitivity for colorectal polyp and cancer detection. Advancements in technology with CCE2 have resulted in much improved diagnostic yield. The three major trials reported sensitivities of 84–88% for 6–9 mm polyps and 88–92% for >10 mm polyps. Reported specificities are 64–82% for 6–9 mm polyps and 89–95% for >10 mm polyps.

• CCE is also increasingly being used in the field of inflammatory bowel disease to assess mucosal inflammation although its performance does not yet rival colonoscopy. It is also being looked at as an alternative to CT colonography in patients with a failed colonoscopy, and initial results are promising.

• ECE had been evaluated mainly as a screening tool for Barrett’s esophagus and esophageal varices. It has a moderately high sensitivity and accuracy for diagnosis and surveillance of Barrett’s esophagus, but not enough to recommend it as a replacement of EGD.

• In varices screening, ECE has a greater patient preference than EGD; however, the literature suggest that ECE is not yet accurate enough to diagnose small, grade 1 varices but has better accuracy for large varices although it is still not comparable to EGD.

• Further technological advances with the advent of magnetically maneuverable capsules are currently under evaluation and may well have a positive impact on the diagnostic yield of both ECE and CCE.

Notes