Copyright
©The Author(s) 2022.
World J Gastroenterol. Dec 21, 2022; 28(47): 6632-6661
Published online Dec 21, 2022. doi: 10.3748/wjg.v28.i47.6632
Published online Dec 21, 2022. doi: 10.3748/wjg.v28.i47.6632
Table 1 Meta-analyses on efficacy of real-time computer aided detection
Ref. | Studies, patients | ADR | Adenoma per patient | Withdrawal time | False positives | ||||
AI | WLI | RR | AI | WLI | Mean difference | Mean difference CADe vs control | |||
Aziz et al[112], 2020 | 3 studies, 2815 patients | 32.9% | 20.8% | 1.58 | 0.47 | 0.26 | 0.20 | 0.9 min (P = 0.03) | 4.87% (n = 137) |
Hassan et al[113], 2021 | 5 studies, 4354 patients | 36.6% | 25.2% | 1.44 | 0.58 | 0.36 | 0.22 | 0.34 min (P = 0.13) | - |
Spadaccini et al[114], 2021 | 6 studies, 5178 patients | 34.0% | 26.6% | 1.78 | - | - | - | No significant difference | - |
Barua et al[115], 2021 | 5 studies, 4311 patients | 29.6% | 19.3% | 1.52 | 0.41 | 0.23 | 0.18 | 0.5 min | 11.2% |
Table 2 Summary of strengths and weakness of advanced imaging technologies in adenoma detection
Modality | Strengths | Weaknesses | |
HD-WLI | Widely available | Marginal incremental benefit over SD-WLI | |
Increased detection of flat, right-sided adenomas and SSAs | |||
Chromoendoscopy | Increased detection of small and flat adenomas | No significant increase in detection of advanced adenomas | |
Increased dysplasia detection in IBD (compared to SD-WLI) | Increased procedural time | ||
May increase polyp detection in high-risk syndromes (serrated polyposis syndrome, HNPCC) | |||
Virtual chromoendoscopy | NBI | May improve flat lesion detection | Loss of brightness and familiarity of colour patterns |
Effective in those with experience using NBI | No evidence of increased total adenoma detection | ||
Less effective when used by proceduralists inexperienced in NBI | |||
i-SCAN | May reduce miss-rates in high-risk populations | Not widely available | |
No difference in adenoma detection in larger studies | |||
Insufficient evidence to recommend use | |||
FICE | Retains familiar colour patterns | Not widely available | |
No difference in ADR | |||
LCI | Retains familiar colour patterns | Not widely available | |
Effective when used by non-LCI experienced proceduralists | Variable evidence regarding overall adenoma detection | ||
Improve adenoma detection, particularly right sided and flat lesions | |||
BLI | Improved adenoma detection and miss rate in smaller studies | Not widely available | |
No difference in ADR in largest study to date | |||
TXI | Retains familiar colour patterns | Not widely available | |
New technology therefore insufficient evidence | |||
AFI | Improved detection of flat/right sided polyps | Not widely available | |
Increased procedure time | |||
No difference in overall ADR | |||
AI | Improves ADR | Expensive currently | |
Improves consistency between proceduralists | Not widely available | ||
Quality assurance | Some increase in procedure time | ||
FME | In theory may improve detection of flat/poorly visible polyps | Insufficient evidence | |
Requires injection/ingestion of tracer |
Table 3 Summary of existing classification systems using advanced mucosal imaging
System | Imaging modality | Polyp features | Accuracy | Complexity | TA/TVAs included | SSAs included |
Kudo | Any | Pits | AUC 0.94[143] | Complex | Yes | No |
NICE | NBI | Vessels and pits | Sensitivity 98%, NPV 97.8%[145] | Moderate | Yes | No |
JNET | NBI | Vessels and pits | AUC 0.97 for JNET 1, 0.84 for JNET 2A, 0.9 for JNET 3 but less accurate for JNET 2B (AUC 0.72)[152] | Moderate | Yes | No |
BASIC | BLI | Vessels, pits and surface | Accurate surveillance prediction in 90%, NPV for rectosigmoid polyps 91%[160] | Moderate | Yes | No |
WASP | Any | Pits, surface, shape | May improve SSA detection[162] | Simple | No | Yes |
mSano | NBI | Vessels, pits and surface | AUC 0.92[169] | Simple | Yes | Yes |
Table 4 Studies on the accuracy of AI for polyp histology prediction
Ref. | Study type | Imaging modality | Number of patients/polyps | Sensitivity | Specificity | NPV | Accurate surveillance interval |
Kominami et al[209], 2016 | Retrospective | NBI | 41 patients, 118 polyps | 93% | 95% | 93% | 92.7% |
Chen et al[210], 2018 | Retrospective | NBI | 284 polyps | 96% | 78% | 90% | - |
Mori et al[211], 2018 | Prospective | NBI | 325 patients, 466 polyps | 93% | 90% | 95% | - |
Renner et al[212], 2018 | Retrospective | WLI, NBI | 100 polyps | 92% | 63% | 90% | - |
Byrne et al[213], 2019 | Retrospective | NBI | 125 polyps | 98% | 83% | 97% | - |
Min et al[214], 2019 | Prospective | LCI | 91 patients, 217 polyps | 83% | 70% | 71% | - |
Sánchez-Montes et al[206], 2019 | Retrospective | WLI | 225 polyps | 92% | 89% | 87% | - |
Horiuchi et al[215], 2019 | Prospective | AFI | 95 patients, 258 polyps | 80% | 95% | 93% | - |
Ozawa et al[216], 2020 | Retrospective | WLI, NBI | 309 polyps | 97% for NBI, 90% for WLI | - | 91% for NBI, 85% for WLI | - |
Jin et al[205], 2020 | Retrospective | NBI | 300 polyps | 83% | 90% | 94% | - |
Zacharia et al[208], 2020 | Retrospective | WLI, NBI | 524 polyps | 96% | 90% | 93% | 94% |
Rodriguez-Diaz et al[217], 2021 | Retrospective | NBI | 119 patients, 280 polyps | 96% | 84% | 91% | 94% |
Van der Zander et al[218], 2021 | Retrospective | WLI, BLI | 54 patients, 60 polyps | 96% | 93% | 88% | - |
Yoshida et al[220], 2021 | Retrospective | BLI | 25 patients, 100 polyps | 91% | 85% | 92% | - |
Sakamoto et al[219], 2022 | Retrospective | WLI, BLI | 604 polyps | 96% for WLI, 96% for BLI | 84% for WLI, 89% for BLI | - | - |
Table 5 Summary and conclusions for each form of advanced mucosal imaging discussed
Modality | Detection | Characterisation | Comment | |
HD-WLI | Advantages: Marginal benefit in overall adenoma detection; and improved detection of right-sided, flat polyps, and SSAs1 | Advantage: Marginal benefit for small adenomas; disadvantage: Insufficient evidence for large polyps | Advantage: Widely available | |
Chromo-endoscopy | Advantage: Increases polyp detection; disadvantage: Increases withdrawal time | Advantages: Highly effective for small polyps (although inefficient); and useful in prediction of invasion depth for large polyps1 | Disadvantage: Increases procedural time | |
Virtual chromo-endoscopy | NBI | Disadvantage: No significant difference in ADR | Advantages: Accurate for distinguishing neoplastic from non-neoplastic small and diminutive polyps; and accurate for prediction of invasion depth1 | Disadvantage: Loss of brightness; neutral: Greater efficacy when used by expert proceduralists |
i-SCAN | Neutral: Variable results, increased detection of flat and right-sided polyps | Advantage: Effective for diminutive and small polyps | ||
FICE | Disadvantage: No significant difference in ADR | Disadvantage: Inferior to NBI | Advantage: Familiar colour spectrum | |
LCI | Advantages: Improves adenoma detection; and effective for non-expert proceduralists1 | Disadvantage: Insufficient evidence | Advantage: Familiar colour spectrum | |
BLI | Disadvantage: No significant difference in ADR | Advantage: Similar to NBI in terms of colour spectrum and accuracy1 | Advantage: Similar colour spectrum to NBI | |
TXI | Advantage: Increases polyp visibility in image-based studies | Disadvantage: Insufficient evidence | Disadvantage: Insufficient evidence; advantage: Familiar colour spectrum | |
AFI | Disadvantage: Insufficient evidence; advantage: Improves detection of flat, right-sided polyps and reduces miss rates | Disadvantage: Inferior to NBI | Disadvantage: Not widely available | |
AI | Advantage: Increases adenoma detection; no significant difference in withdrawal time1 | Advantages: Highly accurate; superior to non-expert endoscopists for histology prediction; not superior to experts using NBI1 | Disadvantage: Not yet widely available | |
FME | Disadvantages: Expensive; insufficient evidence | Disadvantage: Not widely available | ||
Endo-cystoscopy | Neutral: Accurate but requires expertise for interpretation; advantages: Uptake may increase with incorporation of AI | Disadvantages: Requires additional equipment; and not widely available | ||
Multiphoton microscopy | Disadvantage: Insufficient evidence | Disadvantage: Requires additional equipment |
- Citation: Young EJ, Rajandran A, Philpott HL, Sathananthan D, Hoile SF, Singh R. Mucosal imaging in colon polyps: New advances and what the future may hold. World J Gastroenterol 2022; 28(47): 6632-6661
- URL: https://www.wjgnet.com/1007-9327/full/v28/i47/6632.htm
- DOI: https://dx.doi.org/10.3748/wjg.v28.i47.6632