White light computer-aided optical diagnosis of diminutive colorectal polyps in routine clinical practice.

Background and study aims Artificial Intelligence (AI) systems could make the optical diagnosis (OD) of diminutive colorectal polyps (DCPs) more reliable and objective. This study was aimed at prospectively evaluating feasibility and diagnostic performance of AI-standalone and AI-assisted OD of DCPs in a real-life setting by using a white light-based system (GI Genius, Medtronic Co, Minneapolis, Minnesota, United States). Patients and methods Consecutive colonoscopy outpatients with at least one DCP were evaluated by 11 endoscopists (5 experts and 6 non-experts in OD). DCPs were classified in real time by AI (AI-standalone OD) and by the endoscopist with the assistance of AI (AI-assisted OD), with histopathology as the reference standard. Results Of the 480 DCPs, AI provided the outcome "adenoma" or "non-adenoma" in 81.4% (95% confidence interval [CI]: 77.5-84.6). Sensitivity, specificity, positive and negative predictive value, and accuracy of AI-standalone OD were 97.0% (95% CI 94.0-98.6), 38.1% (95% CI 28.9-48.1), 80.1% (95% CI 75.2-84.2), 83.3% (95% CI 69.2-92.0), and 80.5% (95% CI 68.7-82.8%), respectively. Compared with AI-standalone, the specificity of AI-assisted OD was significantly higher (58.9%, 95% CI 49.7-67.5) and a trend toward an increase was observed for other diagnostic performance measures. Overall accuracy and negative predictive value of AI-assisted OD for experts and non-experts were 85.8% (95% CI 80.0-90.4) vs. 80.1% (95% CI 73.6-85.6) and 89.1% (95% CI 75.6-95.9) vs. 80.0% (95% CI 63.9-90.4), respectively. Conclusions Standalone AI is able to provide an OD of adenoma/non-adenoma in more than 80% of DCPs, with a high sensitivity but low specificity. The human-machine interaction improved diagnostic performance, especially when experts were involved.

Artificial intelligence-assisted optical diagnosis for the resect-and-discard strategy in clinical practice: the Artificial intelligence BLI Characterization (ABC) study.

BACKGROUND: Optical diagnosis of colonic polyps is poorly reproducible outside of high volume referral centers. The present study aimed to assess whether real-time artificial intelligence (AI)-assisted optical diagnosis is accurate enough to implement the leave-in-situ strategy for diminutive (≤ 5 mm) rectosigmoid polyps (DRSPs). METHODS: Consecutive colonoscopy outpatients with ≥ 1 DRSP were included. DRSPs were categorized as adenomas or nonadenomas by the endoscopists, who had differing expertise in optical diagnosis, with the assistance of a real-time AI system (CAD-EYE). The primary end point was ≥ 90 % negative predictive value (NPV) for adenomatous histology in high confidence AI-assisted optical diagnosis of DRSPs (Preservation and Incorporation of Valuable endoscopic Innovations [PIVI-1] threshold), with histopathology as the reference standard. The agreement between optical- and histology-based post-polypectomy surveillance intervals (≥ 90 %; PIVI-2 threshold) was also calculated according to European Society of Gastrointestinal Endoscopy (ESGE) and United States Multi-Society Task Force (USMSTF) guidelines. RESULTS: Overall 596 DRSPs were retrieved for histology in 389 patients; an AI-assisted high confidence optical diagnosis was made in 92.3 %. The NPV of AI-assisted optical diagnosis for DRSPs (PIVI-1) was 91.0 % (95 %CI 87.1 %-93.9 %). The PIVI-2 threshold was met with 97.4 % (95 %CI 95.7 %-98.9 %) and 92.6 % (95 %CI 90.0 %-95.2 %) of patients according to ESGE and USMSTF, respectively. AI-assisted optical diagnosis accuracy was significantly lower for nonexperts (82.3 %, 95 %CI 76.4 %-87.3 %) than for experts (91.9 %, 95 %CI 88.5 %-94.5 %); however, nonexperts quickly approached the performance levels of experts over time. CONCLUSION: AI-assisted optical diagnosis matches the required PIVI thresholds. This does not however offset the need for endoscopists' high level confidence and expertise. The AI system seems to be useful, especially for nonexperts.

Educational strategies for colonoscopy bowel prep overcome barriers against split-dosing: A randomized controlled trial.

BACKGROUND: A split-dose (SD) regimen is crucial for colonoscopy quality. Compliance with SD for early morning colonoscopy is generally poor. The present study evaluated whether pre-colonoscopy counselling, in addition to a dedicated leaflet, might increase SD uptake. METHODS: Consecutive 50-69-year-old patients undergoing screening colonoscopy before 10 a.m. were randomized to either receive written information only on bowel preparation (Written Group, WG) or written and oral instructions (Written and Oral Group, WaOG). The leaflet strongly encouraged SD adoption. The primary endpoint was the number of patients adopting SD in each group. The secondary endpoints were predictors of SD uptake, compliance with preparation schemes and cleansing adequacy. RESULTS: A total of 286 patients (143 WG, 143 WaOG) were enrolled (mean age 59.6 ± 6.1 years, men 49.3%). SD was adopted by 114 and 125 patients in the WG and WaOG, respectively (79.7% versus 87.4%, p = 0.079). No significant differences were observed for the proportion of patients with full compliance with preparation scheme (97.9% versus 97.2%, p = 0.99) and of procedures with adequate bowel cleansing (95.6% versus 95.1%, p = 0.77). At multivariate analysis, a > 1 h travel time to the endoscopy service was inversely correlated with SD uptake (odds ratio (OR) 0.30, 95% confidence interval (CI) 0.09-0.98). CONCLUSIONS: Our leaflet guaranteed satisfactory uptake of SD and excellent adherence to the preparation scheme for early morning colonoscopy. Its use might marginalize the need for additional oral instructions, particularly in open-access settings.

Linked color imaging reduces the miss rate of neoplastic lesions in the right colon: a randomized tandem colonoscopy study.

BACKGROUND: Linked color imaging (LCI) is a newly developed image-enhancing endoscopy technology that provides bright endoscopic images and increases color contrast. We investigated whether LCI improves the detection of neoplastic lesions in the right colon when compared with high definition white-light imaging (WLI). METHODS: Consecutive patients undergoing colonoscopy were randomized (1:1) after cecal intubation into right colon inspection at first pass by LCI or by WLI. At the hepatic flexure, the scope was reintroduced to the cecum under LCI and a second right colon inspection was performed under WLI in previously LCI-scoped patients (LCI-WLI group) and vice versa (WLI-LCI group). Lesions detected on first- and second-pass examinations were used to calculate detection and miss rates, respectively. The primary outcome was the right colon adenoma miss rate. RESULTS: Of the 600 patients enrolled, 142 had at least one adenoma in the right colon, with similar right colon adenoma detection rates (r-ADR) in the two groups (22.7 % in LCI-WLI and 24.7 % in WLI-LCI). At per-polyp analysis, double inspection of the right colon in the LCI-WLI and WLI-LCI groups resulted in an 11.8 % and 30.6 % adenoma miss rate, respectively (P < 0.001). No significant difference in miss rate was found for advanced adenomas or sessile serrated lesions. At per-patient analysis, at least one adenoma was identified in the second pass only (incremental ADR) in 2 of 300 patients (0.7 %) in the LCI - WLI group and in 13 of 300 patients (4.3 %) in the WLI - LCI group (P = 0.01). CONCLUSIONS: LCI could reduce the miss rate of neoplastic lesions in the right colon.

Accuracy of capsule colonoscopy and computed tomographic colonography in individuals with positive results from the fecal occult blood test.

BACKGROUND & AIMS: Computed tomographic colonography (CTC) is a reliable option for screening subjects who are unable or unwilling to undergo optical colonoscopy (OC). A colon capsule (PillCam Colon2 [CC2]; GivenImaging Ltd., Yokneam, Israel) has shown promising results in detecting polyps larger than 6 mm. We compared the accuracy of CC2 and CTC in identifying individuals with at least 1 polyp greater than 6 mm and subjects' attitude toward the procedures. METHODS: Fifty individuals (mean age, 59.2 ± 5.8 y; 58% male) with positive results from the immunochemical fecal occult blood test (iFOBT-positive) underwent CC2, CTC, and OC. The unblinded colonoscopy, integrating OC, CTC, and CC2 results, was used as the reference standard. In a per-patient analysis, the accuracy of CC2 and CTC were assessed for individuals with at least 1 polyp 6 mm or larger. Individuals were asked to choose which procedure they would be willing to repeat between CTC and CC2. RESULTS: The combination of OC, CTC, and CC2 identified 16 cases with at least 1 polyp 6 mm or larger (reference standard). CTC identified the polyps with 88.2% sensitivity, 84.8% specificity, a 3.0 positive likelihood ratio, and a 0.07 negative likelihood ratio. CC2 identified the polyps with 88.2% sensitivity, 87.8% specificity, a 3.75 positive likelihood ratio, and a 0.06 negative likelihood ratio. Thirty-nine subjects (78%) said they preferred CC2 to CTC. CONCLUSIONS: CC2 and CTC detect polyps 6 mm and larger with high levels of accuracy; these techniques are effective in selecting iFOBT-positive individuals who do not need to be referred for colonoscopy. CC2 seems to be better tolerated than CTC, and could be a reliable alternative to CTC for iFOBT-positive individuals who are unable or unwilling to undergo OC. ClinicalTrials.gov number: NCT01744509.

Hyoscine N-butylbromide for adenoma detection during colonoscopy: a randomized, double-blind, placebo-controlled study.

BACKGROUND: Hyoscine N-butylbromide (HBB), commonly used during colonoscopy to facilitate cecal intubation, has been proposed to increase the adenoma detection rate (ADR). AIMS: To evaluate whether HBB administration increases the adenoma detection rate and influences patients' tolerance. METHODS: Consecutive colonoscopy outpatients were randomized after cecal intubation to receive either 20mg HBB or placebo i.v. The number, size, histology and location of polyps were recorded. The air retained in the abdomen was either indirectly estimated by ΔAC (difference in the abdominal circumference measured before and after colonoscopy) or directly evaluated by patients' perception (visual analogic scale, range 0-100). RESULTS: 402 patients (44% male; mean age 57.7±12.5years) received either HBB or placebo. No differences in ADR (31.7% vs. 28%, p=0.48), advanced-ADR (7.4% vs. 10.5%, p=0.35) were observed between HBB and placebo group, respectively. A significantly lower detection rate of flat/depressed lesions was observed in the HBB group (0.5% vs. 5.5%, p=0.003). The ΔAC and the bloating perception were comparable between the two groups (p=0.22 and p=0.48, respectively). CONCLUSIONS: HBB administered before colonoscope withdrawal does not increase adenoma detection rate and seems to hamper the visualization of flat/depressed lesions. This finding raises concerns on the indiscriminate use of HBB during colonoscopy.

The impact of narrow band imaging in screening colonoscopy: a randomized controlled trial.

BACKGROUND & AIMS: Narrow band imaging (NBI) is an imaging technique that allows a better definition of capillary pattern and improves the contrast between adenomas and the surrounding mucosa. Conflicting data exist on the ability of NBI to improve detection of colonic neoplasm; the impact of NBI is being tested in several screening scenarios. We evaluated whether the routine use of NBI, compared with white light (WL), during the withdrawal phase of screening colonoscopy improved adenoma detection. METHODS: This randomized controlled study included consecutive 50- to 69-year-old patients with positive immunologic fecal occult blood tests. They were randomly assigned to groups that were examined with WL (n = 108) or NBI (n = 103) during the withdrawal phase of their colonoscopies. The primary end point was the adenoma detection rate. The prevalence of non-polypoid and the total number of adenomas were also evaluated. RESULTS: The number of total and mean per-patient adenomas were 201 (1.95 +/- 2.3) and 198 (1.83 +/- 2.1) in the NBI and WL groups, respectively (P = .69). The adenoma detection rates were 57.3% for patients examined by NBI and 58.3% for those examined by WL (P = .88). A total of 41 non-polypoid adenomas were identified (26 in the NBI and 15 in the WL groups, P = .16). The flat adenoma detection rates were 21.4% and 9.3% in the NBI and WL groups, respectively (P = .019). CONCLUSIONS: The routine use of NBI in screening colonoscopy did not increase the adenoma detection rate. NBI seems to improve the detection of flat adenomas, although additional studies are necessary.

Single bolus of midazolam versus bolus midazolam plus meperidine for colonoscopy: a prospective, randomized, double-blind trial.

BACKGROUND: The aim of this study was to determine whether a single bolus of meperidine in addition to midazolam improves patient tolerance during colonoscopy. METHODS: Consecutive patients undergoing outpatient colonoscopy were randomly assigned in double-blind fashion to receive a single rapid intravenous bolus of 5 mg of midazolam and placebo (Group A, n = 125) or 5 mg midazolam plus 50 mg meperidine (Group B, n = 128). Tolerance (4-point scale: 1 excellent, 4 unbearable), pain (4-point scale: 1 none, 4 severe) and willingness to undergo another colonoscopy were assessed 24 to 48 hours later in a telephone interview conducted by an independent observer blinded to the regimen of sedative medication. RESULTS: Significantly more patients in Group A reported moderate or severe pain (28% vs. 9%; p < 0.001), poor or unbearable tolerance (18% vs. 6%; p < 0.01) and unwillingness to undergo colonoscopy again in the future (14% vs. 5%; p < 0.05). By multivariate analysis, randomization to the midazolam group and younger age were the only variables independently associated with the risk of reporting at least one of these outcomes. Recovery time, frequency of oxygen desaturation, and need for supplemental oxygen were not significantly different between the 2 groups. CONCLUSIONS: The addition of a single bolus of meperidine to midazolam improves patient tolerance and lessens pain during colonoscopy without significantly increasing the frequency of side effects or prolonging recovery time.