Image enhancing technology

There is conflicting evidence regarding the potential for narrow band imaging (NBI), Fuji Intelligent Chromo Endoscopy (FICE), and other techniques of image processing commonly referred to as “virtual chromoendoscopy” to improve detection and characterisation of high-risk lesions. One trial showed an increase in the detection rate of diminutive adenomas (Inoue et al. 2008). There was no difference in adenoma detection rates using NBI technique compared to white-light colonoscopy reported by other published trials (Johanson 2006; Rex 2006; Kaltenbach et al. 2008; Kaltenbach, Friedland & Soetikno 2008; Adler et al. 2009)

The use of autofluorescence was associated with a higher polyp detection rate compared with conventional endoscopy in one study, although the observed improvement was mainly attributable to an increased diagnostic yield of diminutive adenomas (Matsuda et al. 2008; Mayinger et al. 2008; McCallum et al. 2008)

Studies comparing the performance of colonoscopy with high definition versus standard colonoscopes did not show an increase in the detection rate of adenomas or hyperplastic polyps when using highdefinition instruments (East et al. 2008; Pellise et al. 2008; Burke et al. 2009)

The results of diagnostic accuracy studies showed better accuracy of NBI colonoscopy compared to standard colonoscopy in differentiating between neoplastic and non-neoplastic lesions (Su et al. 2006; Katagiri et al. 2008) (III). In the recent Cochrane review of chromoendoscopy, it was suggested that NBI may become the gold standard in enhanced techniques for detection of colorectal lesions, but with the advantage of reduced procedure time compared to chromoendoscopy. One trial comparing diagnostic accuracy of NBI with chromoendoscopy on 99 Patients has been retrieved (Tischendorf et al. 2007). The study did not find a significant difference in accuracy between the two technologies for the differentiation of neoplastic vs. nonneoplastic lesions. Further trials comparing NBI and chromoendoscopy are needed. 

Further experience and evidence about efficacy, benefits and potential adverse effects, as well as cost-effectiveness, are required before additional technologies can be recommended for routine, panEuropean use in colorectal cancer screening and diagnosis. Particularly in the screening context, improvements in detection and diagnosis may be accompanied by unacceptable decreases in specificity, and/or disproportionate, unacceptable increases in cost, measured both in human and financial resources. 

After sufficient standardisation of procedures and protocols in feasibility studies, pilot studies conducted in the framework of population-based screening programmes, and based on a randomised public health policy, could provide appropriate evidence to justify future recommendations for widespread implementation of new technologies. 

In view of the above it is recommended that: 

• The provision and maintenance of equipment in the endoscopic unit should be carefully managed based on local guidelines that comply with relevant national and pan-European guidelines containing accepted, published recommendations and standards. 
•  Flexible video endoscopes and the facility for focal application of dye to the lesion should be used in colorectal cancer screening (III – B).Rec 5.12 
•  The volume of equipment should match the demand put upon it to maximise efficiency and avoid patient delays (VI - B).Rec 5.11 
•  There should be an adequate supply of accessories suited to the endoscopic interventions undertaken within the unit (VI - B).Rec 5.13
•  Use of re-usable accessories should be based on national policy (VI - B).Rec 5.14 
•  There should be properly maintained resuscitation equipment in the endoscopy room and recovery area (VI - B).Rec 5.15 
•  Maintenance of equipment should be undertaken by competent staff (V - A).Rec 5.16 
•  There should be regular review of the functioning of all endoscopes, in accordance with manufacturer specifications and instructions and relevant national or pan-European guidelines (VI - B).Rec 5.17 
•  The results of the review should be available at all times in the endoscopy unit (VI - A).Rec 5.18