Narrow Band Imaging in Diagnosis of Colorectal Polyps

Study Overview
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Brief Summary
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Optical diagnosis of colorectal polyps is a promising tool to avoid risks of unnecessary polypectomies and to save costs of tissue pathology. NICE (NBI International Colorectal Endoscopic) and WASP (Workgroup on Serrated Polyps and Polyposis) classification were developed for diagnosis of adenomatous and sessile serrated polyps, respectively.

Detailed Description
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Near-focus (NF) narrow-band imaging (NBI) is an image-magnifying technology which enables optical magnification of up to 65x in near focus (NF) compared with 52x in normal standard focus (SF) with the simple push of a button of the endoscope to be interchangeable between NF and SF. There were few studies comparing diagnostic accuracy between NF and SF in the diagnosis of colorectal polyps. So, our aim of the current study is to compare accuracy of NF NBI compared with SF NBI in the optical diagnosis of neoplastic and non-neoplastic polyp and the accuracy of NF NBI versus SF NBI in distinguishing serrated adenoma from hyperplastic polyp in sessile lesions using histologic evaluation as the gold standard.

Official Title
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Near-focus Versus Normal-focus Narrow Band Imaging Colonoscopy in Diagnosis of Colorectal Polyps Based on Combined NICE and WASP Classification: a Randomized Controlled Trial

Conditions
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Colorectal Neoplasms, Colorectal Polyp

Intervention / Treatment
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* Diagnostic Test: Near Focus NBI
* Diagnostic Test: Standard Focus NBI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who were scheduled for colonoscopy at NKC institute Exclusion Criteria: Inflammatory bowel disease Polyposis syndrome Colorectal cancer Active gastrointestinal bleeding Pregnant woman Inadequate bowel preparation Contraindication for polyps removal

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Near Focus NBI<br>Use of the Near Focus NBI to make optical diagnosis | Diagnostic Test: Near Focus NBI<br>* Colonoscopy with near focus narrowing band imaging technology . Optical specifications include a 2 mm near field focal depth. Optical diagnosis of polyps were according to NICE and WASP, respectively.<br>|
| Active Comparator: Standard Focus NBI<br>Use of the Standard Focus NBI to make optical diagnosis | Diagnostic Test: Standard Focus NBI<br>* Colonoscopy with narrow band imaging technology.Optical diagnosis of polyps were according to NICE and WASP, respectively.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of accurate polyp histology predictions by the Endoscopists in the two groups. | Measure of the percentage of accurate predictions by the endoscopists in the differentiation of neoplastic from non neoplastic colorectal lesions, using the high definition NBI colonoscopy with and without near focus features | At the time of procedure | 
| Rate of accurate diagnosis of sessile serrated polyps/adenoma by the Endoscopists in the two groups. | Measure of the percentage od accurate predictions by the endoscopists in the differentiation of sessile serrated polyps/adenoma from hyperplastic polyps, using the high definition NBI colonoscopy with and without near focus features. | At the time of procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The polyp detection rate | The prevalence of patients with at least one polyp was detected | At the time of procedure | 
| The adenoma detection rate | The prevalence of patients with at least one adenoma was detected | At the time of procedure | 
| Diagnostic Characteristics | Compare the diagnostic characteristic (sensitivity, specificity, positive predictive value and negative predictive value) using the high definition narrow band imaging colonoscopy with and without near focus features. | At the time of procedure |