Detection of Colorectal Neoplasms Using Linked Color Imaging: A Prospective,Randomized, Tandem Colonoscopy Trial

Background and aimsA higher adenoma detection rate (ADR) has been shown to be related to a lower incidence and mortality of colorectal cancer. We analyzed the efficacy of linked color imaging (LCI) by assessing the detection, miss, and visibility of various featured adenomas as compared with white light imaging (WLI).MethodsThis was a prospective, randomized, tandem trial. The participants were randomly assigned to 2 groups: first observation by LCI, then second observation by WLI (LCI group); or both observations by WLI (WLI group). Suspected neoplastic lesions were resected after magnifying image-enhanced endoscopy. The primary outcome was to compare the ADR during the first observation. Secondary outcomes included evaluation of adenoma miss rate (AMR) and visibility score.ResultsA total of 780 patients were randomized, 700 of whom were included in the final analysis. The ADR was 69.6% and 63.2% in the LCI and WLI groups, respectively, with no significant difference. However, LCI improved the average ADR in low-detectors compared with high-detectors (76.0% vs 55.1%; P < .001). Total AMR was 20.6% in the LCI group, which was significantly lower than that in the WLI group (31.1%) (P < .001). AMR in the LCI group was significantly lower, especially for diminutive adenomas (23.4% vs 35.1%; P < .001) and nonpolypoid lesions (25.6% vs 37.9%; P < .001) compared with the WLI group.ConclusionAlthough both methods provided a similar ADR, LCI had a lower AMR than WLI. LCI could benefit endoscopists with lower ADR, an observation that warrants additional study. (UMIN Clinical Trials Registry, Number: UMIN000026359).     

Prospective Study Comparing Multislice CT Colonography With Colonoscopy in the Detection of Colorectal Cancer and Polyps

PURPOSE: Multislice CT colonography is an alternative to colonoscopy. The purpose of this study was to compare multislice CT colonography with colonoscopy in the detection of colorectal polyps and cancers. METHODS: Between June 2000 and December 2001, 45 males and 35 females (median age, 68 (29–83) years) with symptoms of colorectal disease were studied prospectively. All patients underwent multislice CT colonography and colonoscopy, and the findings were compared. RESULTS: Colonoscopy was incomplete in 18 (22 percent) patients because of obstructing lesions or technical difficulty, and multislice CT colonography was unsuccessful in 4 (5 percent) because of fecal residue. Colonoscopy was normal in 26 patients and detected 29 colorectal cancers and 33 polyps in 35 patients, diverticulosis in 16 patients, and colitis in 3 patients. Multislice CT colonography identified 28 of 29 colorectal cancers with one false negative and one false positive (sensitivity, 97 percent; specificity, 98 percent; positive predictive value, 96 percent; negative predictive value, 98 percent). Multislice CT colonography identified all 12 polyps measuring 10 mm in diameter (sensitivity, 100 percent), 5 of 6 measuring 6 to 9 mm in diameter (sensitivity, 83 percent), 8 of 15 polyps 5 mm (sensitivity, 53 percent), and false-positive for 8 polyps. The overall sensitivity was 74 percent and specificity 96 percent. The positive predictive value for polyps was 88 percent, and the negative predictive value was 90 percent. Multislice CT colonography also detected 5 of 16 patients with diverticulosis (sensitivity, 31 percent; specificity, 98 percent) and colitis in 2 of 3 patients (sensitivity, 67 percent; specificity, 100 percent). In ten (13 percent) patients, extracolonic findings on multislice CT colonography altered management and included five patients with colorectal liver metastases. In 15 (19 percent) patients, there were incidental findings that did not demand further investigation. CONCLUSIONS: The results from this study indicate that the efficacy of multislice CT colonography in the detection of colorectal cancers and polyps 6 mm is similar to colonoscopy. Multislice CT colonography allows clinical staging of colorectal cancers, outlines the whole length of the colon in obstructing carcinoma when colonoscopy fails, and can identify extracolonic causes of abdominal symptoms.     

Prospective Observation of Small Adenomas in Patients After Colorectal Cancer Surgery Through Magnification Chromocolonoscopy

Purpose This study was designed to confirm the safety of not removing small adenoma in patients who undergo colorectal cancer surgery. Methods Patients who underwent surveillance colonoscopy after surgery were enrolled. The study was approved by our institutional review board. Colonoscopy was performed with magnification chromocolonoscopy. Benign adenomas of 6 mm or less in size, diagnosed based on both nonmagnified and magnified observation, were left unresected with a maximum of three polyps per patient. The sites of the polyps were marked by tattooing. Interval colonoscopy was performed predominantly yearly or biennially. Increase in size by 2 mm or larger was defined as significant. In follow-up, polyps were removed if they grew larger than 6 mm, were suspicious for high-grade dysplasia, or the patients requested to have polyps removal. Results Five hundred polyps in 284 patients met the above criteria and were not resected, and 412 polyps were followed by repeat colonoscopy. The mean observation period was 3.6 ± 2.2 years and the mean number of repeat colonoscopy was 3.6 ± 1.6. At the final colonoscopy, 71 percent of 412 polyps showed no change in size, 15 percent increased, 3 percent decreased, and 11 percent could not be identified. Eighty-eight polyps were resected endoscopically, and histology showed neither cancer nor adenomas with high-grade dysplasia. Two hundred fifty-five polyps detected in the same patient cohort during index/repeat colonoscopy were removed, including four adenomas with high-grade dysplasia and two T1 cancers. Conclusions Leaving small polyps is safe even in patients who have undergone colorectal cancer surgery, provided that careful observation is guaranteed. Supported in part by Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan. Read at the meeting of The American Society of Colon and Rectal Surgeons, St. Louis, Missouri, June 2 to 6, 2007.     

A Comparison of High-Definition Versus Conventional Colonoscopes for Polyp Detection

Background  

High-resolution, high-definition colonoscopes (HD) with 170° angle of view providing brighter images, sharper resolution, and a 30° wider field of view than conventional colonoscopes (CC) are available. The impact of these innovations on enhancing the detection of clinically important colonic lesions or over detection of clinically insignificant colonic lesions is not well established.     

Effect of Electroanatomically Guided Versus Conventional Catheter Ablation of Typical Atrial Flutter on the Fluoroscopy Time and Resource Use: A Prospective Randomized Multicenter Study

Aims: Radiofrequency catheter ablation of typical atrial flutter is one of the most frequent indications for catheter ablation in electrophysiology laboratories today. Clinical utility of electroanatomic mapping systems on treatment results and resource utilization compared with conventional ablation has not been systematically investigated in a prospective multicenter study. Methods and Results: In this prospective, randomized multicenter study, the results of catheter ablation to cure typical atrial flutter using conventional ablation strategy were compared with electroanatomically guided mapping and ablation (Carto®). Primary endpoints of the study were procedure duration and fluoroscopy exposure time, secondary endpoints were acute success rate, recurrence rate, and resource utilization. A total of 210 patients (169 men, 41 women, mean age 63 ± 10 years) with documented typical atrial flutter were included in the study. Acute ablation success, that is, demonstration of bidirectional isthmus block, was achieved in 99 of 105 patients (94%) in the electroanatomically guided ablation group and in 102 of 105 patients (97%) in the conventional ablation group (P > 0.05). Total procedure duration was comparable between both study groups (99 ± 57 minutes vs 88 ± 54 minutes, P > 0.05). Fluoroscopy exposure time was significantly shorter in the electroanatomically guided ablation group (7.7 ± 7.3 minutes vs 14.8 ± 11.9 minutes; P < 0.05). Total recurrence rate of typical atrial flutter at 6 months of follow‐up was comparable between the 2 groups (respectively for the CARTO and conventional group 6.6% vs 5.7%, P > 0.05). The material costs per procedure in the electroanatomically guided and conventional groups (NaviStar® DS vs Celsius® DS) was €3035 (USD 3,870) and €2133 (USD 2,720), respectively. Conclusions: This multicenter study documented that cavotricuspid isthmus ablation to cure typical atrial flutter was highly effective and safe, both in the conventional and the electroanatomically guided ablation group. The use of electroanatomical mapping system significantly reduced the fluoroscopy exposure time by almost 50%, however, at the expense of increased cost of the procedure.     

Remifentanil Compared with Midazolam and Pethidine Sedation During Colonoscopy: A Prospective, Randomized Study

Purpose The objective of our study was to compare the safety and efficacy of remifentanil during colonoscopy with those of the standard combination of midazolam and pethidine. Methods One-hundred and sixteen consecutive patients scheduled for colonoscopy were randomly assigned to groups A or B. Patients in group A (n = 56) received intravenous (IV) midazolam and pethidine. Patients in group B (n = 60) received IV remifentanil. Results Recovery was faster in group B (0 min) than in group A (56 ± 11.3 min) (P < 0.001). There was a marked difference between groups B and A with regard to the time of hospital discharge—28.7 ± 4.3 and 148.9 ± 34 min, respectively (P < 0.001). Patients in group A rated the procedure as comfortable, as also did those in group B. A combination of midazolam and pethidine had a greater affect on patients’ cardiorespiratory characteristics. Conclusion Remifentanil during colonoscopy provides sufficient pain relief with better hemodynamic stability, less respiratory depression, and significantly faster recovery and hospital discharge than moderate sedation with midazolam and pethidine.     

聚乙二醇与磷酸钠在结肠镜检查前肠道准备的比较

目的 对比聚乙二醇与磷酸钠在结肠镜检查前肠道准备的效果、依从性以及对血生化指标的影响.方法 78例结肠镜检查者随机给予聚乙二醇电解质溶液或磷酸钠进行肠道准备,单盲法评价肠道清洁效果,问卷调查患者排便性状和次数以及对于药物的口感.另外,肠道准备前后检测各种血生化指标和体重,对比两种药物的差异.结果 所有入选者都能饮完聚乙二醇电解质液或磷酸钠溶液,入选者似乎更容易接受磷酸钠.口感计分磷酸钠组为3.11±0.60,聚乙二醇组为2.85±0.74,两组无统计学显著性差异(P=0.09).磷酸钠组肠道准备满意度计分2.32±0.66,聚乙二醇组为2.00±0.64(P=0.035),磷酸钠组肠道准备后血磷水平升高(由1.05±0.17升高至1.52±0.58,P＜0.001),而血钙(P＜0.001)降低,血钠(P=0.022)降低,但无明显临床症状.与聚乙二醇组相比,磷酸钠组有引起低血钾的趋势(P＜0.096),而磷酸钠组肠道准备后与准备前相比,血钾下降有统计学差异(P=0.003).结论 从肠道准备效果上来看,磷酸钠优于聚乙二醇.在口感上二者相比虽无统计学差异,但入选者更倾向于接受磷酸钠.虽然没有临床症状,应警惕磷酸钠肠道准备后低钙、低钠、高磷血症,且血磷升高幅度非常明显,对于肾功能不全的患者,尤需谨慎.