We emphasize the importance of confidence levels in making an optical diagnosis. The use of confidence levels allows calibration and standardization between endoscopists with varying levels of diagnostic ability and reduces interobserver variation. Thus, if a polyp lacks clear endoscopic features precluding confident endoscopic assignment of histology, the endoscopist could still resect and submit it for pathologic assessment (Figure 1).
Documentation
Photo documentation and archiving are a key component in both the study and clinical implementation of optical diagnosis for accreditation and quality assurance.
The first step is to optimize the processor, monitor, and capture settings to display and capture high-quality representative images of the polyp. The endoscope manufacturer may assist to set optimal image parameters on the endoscope processor. Digital integration of the polyp image and optical diagnosis into the endoscopy reporting system is necessary for efficient real-time relay of information as well as reliability for review. Such archiving would permit both self and formal audits.
Limitations
Other factors may hinder the outcomes of a study of optical diagnosis. A lack of academic interest or lack of financial incentive may influence the commitment or performance during a study. Physicians with direct or indirect ownership in a pathology facility should at a minimum declare a potential conflict of interest.
Discussion
Our comments are directed only as an effort to make results of published trials more consistent. Whether and to what extent specific factors unique to community physicians may contribute to the recent less promising results remain uncertain. These and other as yet unconsidered factors will likely also affect academic physicians who do not have a special interest in endoscopy or in this endoscopic issue. Such variable performance in optical diagnosis could be interpreted to mean that optical diagnosis can and should be implemented in the context of a credentialing program. Thus, because many studies have met proposed thresholds and some have not, accurate optical diagnosis is possible, but individual physicians need to prove their skill to start the practice. Such a policy could be implemented in any practice whether academic or community-based.
The actual implementation of optical diagnosis must also address other obstacles. For example, there are often institutional policies requiring submission of resected tissue to pathology. Furthermore, adenoma detection rate (ADR) has emerged as the most important quality indicator in colonoscopy. In a resect and discard policy, ADR would have to be measured by photography, which would require endoscope manufacturers to provide image storage with quality that reproduces the image seen in real time and that can be easily audited by experts to verify ADR. Such image storage would also be necessary to provide medical-legal protection for endoscopists. Finally, the current fee-for-service reimbursement model does not result in optimal financial incentives to drive a resect and discard policy forward. However, certain reimbursement models under consideration such as bundled payment and reference payment could make resect and discard more attractive to endoscopists.
Conclusion
We hope that the framework we describe will be useful in improving the accuracy, completeness of reporting, and meta-analysis of future studies of the diagnostic characteristics of optical diagnosis, with the ultimate goal of incorporating this paradigm shift into routine day-to-day clinical practice.
Supplementary Material
Supplementary Figure 1
References
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