Ultra-minimally invasive endoscopic techniques and colorectal diseases: Current status and its future

Table 1 Technological advancement in endoscopic diagnosis and treatment of colorectal diseases

No.	Techniques	Technology	Clinical use diagnostic/therapeutic	Ref.
1	Chromoendoscopy	Real-time tissue enhancement using biocompatible dyes	Polyp and adenoma detection, differentiation of benign from malignant lesions, dysplasia associated with IBD	[111-114]
2	Narrow band imaging	Physical spectral filters generate narrow bands of 415 and 540 nm in center wavelength	Adenoma detection, dysplasia associated with IBD	[115,116]
3	Blue light imaging	Narrowed spectrum LED light of 410 nm and 450 nm enabling haemoglobin excitation and a positive mucosal contrast	Differentiation of non-neoplastic from neoplastic lesions, in vivo histology	[117-119]
4	Autofluorescence endoscopy	Fluorescence of fluorophores differentiate tissues	Adenoma detection, differentiation of non-neoplastic lesions from neoplastic lesions	[120-123]
5	Flexible spectral imaging color enhancement	This differentiation is based on the surface capillary pattern	Differentiation of non-neoplastic from neoplastic lesions, in vivo histology	[124-126]
6	Linked color imaging	Pre-processing narrow band LED radiation and post-processing color technology to separate imported colors into red, green, and blue what enhances color differences	Polyp detection	[127-129]
7	i-SCAN	Enhancement of the image contrast through a real-time post-processing algorithm, basing the different reflective properties of normal and abnormal mucosa	Adenoma detection, in vivo histology, disease activity in IBD, detection of neoplasia in IBD	[130-133]
8	i-SCAN OE	Incorporation of a digital pre-processor optical enhancement to improve visualization of mucosal vascular pattern	Detection of pre-malignant lesions	[134]

IBD: Inflammatory bowel disease; LED: Light emitting diode.

Table 2 Commercial artificial intelligence algorithms and its clinical use in colorectal diseases[135]

No.	Product name	Company	Integration	CAD mode	Regulatory (country, year)	Clinical use
1	EndoBRAIN	Cybernet System Co. (Tokyo, Japan)	CF-290ECI, Olympus Co.	CADx	Japan, 2018	Colorectal polyps endocytoscopy-computer-aided diagnosis
2	EndoBRAIN-EYE	Cybernet System Co.	Olympus colonoscopes	CADe	Japan, 2020	Colorectal polyps endocytoscopy-computer-aided diagnosis
3	EndoBRAIN-PLUS	Cybernet System Co.	CF-290ECI, Olympus Co.	CADx	Japan, 2020	Image enhanced colonoscopy
4	EndoBRAIN-UC	Cybernet System Co.	CF-290ECI, Olympus Co.	CADx	Japan, 2020	Image enhanced colonoscopy
5	GI Genius	Medtronic Co. (Dublin, Ireland)	Multi vendors possible	CADe	United States, Europe, 2019	Colorectal polyps
6	DISCOVERY	Pentax Medical Co. (Tokyo, Japan)	Pentax colonoscope	CADe	Europe, 2020	Colorectal polyps
7	ENDO-AID	Olympus Co. (Tokyo, Japan)	Olympus colonoscopes	CADe	Europe, 2020	Colorectal polyps, real-time aid, texture and color enhancement imaging
8	CAD-EYE	Fujifilm (Tokyo, Japan)	Fukifilm colonoscope	CADe CADx	Europe, Japan, 2020	Colorectal polyps, real-time aid
9	EndoScreener	Shanghai Wision AI Co. (Shanghai, China)	Multi vendors	CADe	Europe, United States, 2021	Colorectal polyps
10	WISE VISION	NEC Co. (Tokyo, Japan)	Multi vendors	CADe	Japan, Europe, 2020	Colorectal polyps

Table 3 Results of combined endo-laparoscopic surgery, segmental resection and outcome

No.	Number of patients	Complications (%)	Length of stay (d)	Procedure time (min)	Cost (dollars)/others	Ref.
1	23 SR; 23 CELS	CELS: 13; SR: 47.8	CELS: 4; SR: 7	CELS: 135; SR: 200	-	Golda et al[107], 2022
2	11 CELS; 11 SR	CELS: 0; SR: 9	CELS: 0-3; SR: 2-5	CELS: 66.73; SR: 204.7	CELS: 5523.29; SR: 12626.33	Jayaram et al[108], 2019
3	5 CELS; 9 SR	CELS: 0; SR: 33.3	CELS: 1; SR: 5	CELS: 159; SR: 205	-	Lee et al[109], 2013

CELS: Combined endo-laparoscopic surgery; SR: Segmental resection.

Table 4 Results of published series on surgery vs endoscopic intervention in malignant colorectal polyps and colonic obstruction

No.	Patients	Diagnosis	Complications (%)	Outcome (surgery vs endoscopy)	Ref.
1	Of 2077 patients: Surgical resection (1340), endoscopic polypectomy (737)	Malignant polyp	Surgery: 8.8. Endoscopy: 1.4	1-yr OS (92% vs 75%); 5-yr OS (88% vs 62%)	Cooper et al[136], 2012
2	Of 13157 patients: Surgical resection (11113), endoscopic polypectomy (2044)	Malignant polyp	-	Right colon polyps: < 20 mm polyp: 94.5% vs 94.3% (P = 0.9); 20-39 mm: 91.8% vs 74.2% (P < 0.01); > 40 mm: 92.4% vs 60% (P < 0.01)	Gangireddy et al[137], 2018
3	Of 31062 patients: Surgical resection (28469), endoscopic polypectomy (2593)	Malignant polyp	-	5-yr OS: 86.1% vs 80.6% (P < 0.05)	Lowe et al[138], 2020
4	Of 12 studies (meta-analysis)	Malignant obstruction	SEMS: 32.7. ES: 48.2 (RR = 0.61, 95%CI: 0.41-0.91)	Mortality (RR = 1.06, 95%CI: 0.55-2.04). Successful primary anastomosis (SEMS: 69.75% vs ES: 55.07%) (RR = 1.26, 95%CI: 1.01-1.57)	Cirocchi et al[55], 2021
5	Of 167 patients: SEMS (115), ES (52)	Malignant obstruction	SEMS: 20. ES: 30.8	5-yr OS: 85.6 vs 82.6% (P = 0.68)	Kim et al[54], 2023

CI: Confidence interval; ES: Emergency surgery; OS: Overall survival; RR: Risk ratio; SEMS: Self expanding metallic stent.