Optical diagnosis of small colorectal polyps during colonoscopy: when to resect and discard?

Comparing the efficacy and safety of Dexmedetomidine/Ketamine with Propofol/Fentanyl for sedation in colonoscopy patients: A double-blinded randomized clinical trial

BACKGROUND

In this double-blinded randomized clinical trial, we aimed to compare the safety and efficacy of a combination of dexmedetomidine and ketamine [DK] with propofol and fentanyl [PF] for sedation in colonoscopy patients.

METHODS

In this study, 64 patients who underwent colonoscopy were randomized into two groups: 1) A, which received PF, and 2) B, which received DK for sedation. Among 64 patients, 31 patients were included in PF, and 33 patients were included in the DK group. Both groups were similar in terms of demographics. Patients' sedation score (based on Ramsay sedation scale) and vital signs were recorded at 2, 5, 10, and 15 minutes. Complications including apnea, hypotension, hypoxia, nausea, and vomiting, along with gastroenterologist satisfaction and patients' pain score (based on Wong-Baker faces pain assessment scale), were recorded by a checklist. Data were analyzed by SPSS v.18 software, using chi-square, independent t-tests, and repeated measures analysis with p<0.05 as the criterion for significant differences.

RESULTS

The mean score of sedation was 4.82±0.49 in the DK group and 5.22±0.45 in the PF group [p value=0.001]. Serious complications, including hypotension [p value=0.005] and apnea [p value=0.10] were significantly higher in the PF group. Satisfaction of gastroenterologist [p value= 0.400] and patients' pain score [p value = 0.900] were similar among groups.

CONCLUSION

Combination of DK provides sufficient sedation with fewer complications in comparison with PF in colonoscopy patients.

A Review of New and Emerging Techniques For Optical Diagnosis of Colonic Polyps

BACKGROUND AND AIMS

Endoscopic imaging is a rapidly progressing field and benefits from miniaturization of advanced imaging technologies, which may allow accurate real-time characterization of lesions. The concept of the "optical biopsy" to predict polyp histology has gained prominence in recent years and may become clinically applicable with the advent of new imaging technology. This review aims to discuss current evidence and examine the emerging technologies as applied to the optical diagnosis of colorectal polyps.

METHODS

A structured literature search and review has been carried out of the evidence for diagnostic accuracy of image-enhanced endoscopy and emerging endoscopic imaging technologies. The image-enhanced endoscopy techniques are reviewed, including their basic scientific principles and current evidence for effectiveness. These include the established image-enhancement technologies such as narrow-band imaging, i-scan, and Fuji intelligent chromoendoscopy. More recent technologies including optical enhancement, blue laser imaging, and linked color imaging are discussed. Adjunctive imaging techniques in current clinical use are discussed, such as autofluorescence imaging and endocytoscopy. The emerging advanced imaging techniques are reviewed, including confocal laser endomicroscopy, optical coherence tomography, and Raman spectroscopy.

CONCLUSIONS

Large studies of the established image-enhancement techniques show some role for the optical diagnosis of polyp histology, although results have been mixed, and at present only the technique of narrow-band imaging is appropriate for the diagnosis of low-risk polyps when used by an expert operator. Other image-enhancement techniques will require further study to validate their accuracy but show potential to support the use of a "resect-and-discard" approach to low-risk polyps. New technologies show exciting potential for real-time diagnosis, but further clinical studies in humans have yet to be performed.

Patient acceptance of the optical diagnosis and misdiagnosis of diminutive colorectal polyps

BACKGROUND AND AIMS

Optical diagnosis allows for real-time endoscopic assessment of colorectal polyp histology and consists of the resect and discard and diagnose and leave paradigms. This survey assessed patient acceptance of optical diagnosis and their responses to a hypothetical doomsday scenario.

METHODS

We conducted a 3-month cross-sectional survey of colonoscopy outpatients presenting to an Australian academic endoscopy center.

RESULTS

A total of 981 patients completed the survey (76.0% response rate). The 60.8% of patients who supported resect and discard were more likely to be older men who co-supported diagnose and leave. Fewer patients (49.6%) supported diagnose and leave. A family history of missed cancer diagnosis (odds ratio [OR], 0.59; P = .003) was significantly associated with rejection of resect and discard, and a personal or family history of bowel cancer (OR, 0.7; P = .04) was significantly associated with rejection of diagnose and leave. In the hypothetical scenario of a cancerous polyp incorrectly left in situ leading to stage III disease, 208 (21.2%) patients would definitely ask for financial compensation, 584 (59.5%) were unsure, and 189 (19.3%) would definitely not seek compensation. The patient-proposed median value of compensation sought was $760,000 USD ($1,000,000 AUD; $1 AUD = $0.76 USD). Notably, 18.5% would be willing to give optical diagnosis another chance after this error.

CONCLUSION

Patient support for optical diagnosis is limited, and those who are not supporters are more likely to seek financial compensation if errors occur.

Optical diagnosis of colorectal neoplasia: A Western perspective

Optical diagnosis is an emerging paradigm in Western endoscopic practice for the colonoscopic management of diminutive polyps, and includes two complementary clinical strategies: 'resect and discard', in which diminutive high-confidence adenomas are identified, and then removed and discarded without pathological assessment; and 'diagnose and leave', where diminutive high-confidence hyperplastic polyps are identified in the rectosigmoid and then left without resection or biopsy. Like other aspects of colonoscopy performance, adoption of optical diagnosis in Western practice is limited by operator dependency and variation in clinical effectiveness. There is substantial potential for optical diagnosis of colorectal neoplasia during colonoscopy to alleviate the rising costs of health care in the West. However, operator dependence in diagnostic performance together with critical system factors such as informed consent, credentialing, medical legal support and reimbursement incentives must be overcome before optical diagnosis of diminutive lesions is considered for widespread adoption in Western clinical practice.