Mark B. Pochapin, MD, FACG1, Abraham Khan, MD1, Jonathan Rosenberg, MD1, Shannon Chang, MD, MBA2, Xiaochun Li, PhD3, Judith Goldberg, ScD3, Ghoncheh Ghiasian, MPH1, Bhavna Sharma, BS1, Rita M. Knotts, MD, MS1, David M. Poppers, MD, PhD1; 1New York University Langone Medical Center, New York, NY; 2New York University, Langone Health, New York, NY; 3New York University School of Medicine, New York, NY
Introduction: Multi-society recommendations state, “Given the importance of polyp size for informing surveillance intervals, documentation of a polyp > 10 mm within a report should be accompanied by an endoscopic photo of the polyp with comparison to an open snare or open biopsy forceps” (1). We evaluate the feasibility of the Napoleon, an endoscopically-deployed small ruler to more accurately measure and document the size of colon polyps. Methods: The Micro-Tech Endoscopic Gauge (Non-FDA approved) named Napoleon, a catheter with a 15 mm ruler calibrated in 1 mm intervals with demarcations every 5 MM, was advanced through the biopsy channel of a colonoscope and positioned adjacent to a polyp to accurately measure polyp size (Image 1). Polyps sizes were first assessed visually and then measured using the Napoleon. Patients included were 50 to 85 years of age and undergoing screening or surveillance colonoscopy. Napoleon placement, extension/retraction, and photograph acquisition were evaluated on a 1-10 scale (1=Easy, 10=Difficult). Results: 23 patients were evaluated by 6 physicians. A total of 36 polyps were found. Each score represents the average of several polyps if more than one polyp was identified per patient (Table 1). The most polyps found in any patient was 3. Each polyp size was placed into 1 of 3 categories (Table 2): 1-5 mm (Diminutive), 6-9 mm (Small) and > 10 mm (Large). 30 of the 36 total polyps (83%) were diminutive. 3 polyps were downgraded into the next smaller size category after measurement with the Napoleon – specifically, 1 polyp (33%) dropped from small to diminutive size and 2 polyps (67%) dropped from large to small size. Discussion: Prior studies on polyp size have shown that visual assessment is inaccurate (2). This study demonstrates the ease and feasibility of the Napoleon as an endoscopic measuring device. The majority of polyps found were diminutive (1-5 mm) and explains why there is such a minute difference noted in the weighted mean polyp size (0.28 mm). Of the 3 polyps that were visually assessed to be > 10 mm, 2 of those polyps (67%) were measured to be < 10 mm, changing recommended surveillance from 3 years to 7-10 years (1). Further studies utilizing an endoscopic measuring tool such as the Napoleon are needed to evaluate the effect of accurate polyp measurement on our clinical management, training, and colonoscopy surveillance intervals. References
Gupta et al., Am J Gastroenterol. 2020;115(3):415-434
Eichenseer PJ et al., Dis Colon Rectum 2013 Mar;56(3):315-21
Image 1: Photograph of the Napoleon endoscopic ruler calibrated in 1 mm markings (A). Endoscopic image of the Napoleon ruler adjacent to a small polyp that measures 6 mm (B).
Table 1: Score results for the Napoleon measuring device placement, photo acquisition, and extension/retraction (Scale = 1-10, with 1 being the easiest and 10 being the most difficult) and difference in visual and measured polyp sizes
Table 2: Visual and Napoleon measured polyp size comparison by size category: Diminutive = 1-5 mm, Small = 6-9 mm, Large >10 mm
Disclosures: Mark Pochapin: Micro-Tech – Patent Holder. Abraham Khan indicated no relevant financial relationships. Jonathan Rosenberg indicated no relevant financial relationships. Shannon Chang indicated no relevant financial relationships. Xiaochun Li indicated no relevant financial relationships. Judith Goldberg indicated no relevant financial relationships. Ghoncheh Ghiasian indicated no relevant financial relationships. Bhavna Sharma indicated no relevant financial relationships. Rita Knotts indicated no relevant financial relationships. David Poppers: Olympus – Consultant.