How does Virtual Scale Endoscopy improve the accuracy of measuring colorectal polyps?

Accurate measurement of colorectal polyps is crucial for determining cancer risk, guiding removal technique, and setting follow-up intervals. Traditional methods like visual assessment, biopsy forceps, or endoscopic rulers often lead to errors. Virtual Scale Endoscopy (VSE) is a newer technology that projects a laser-calibrated scale directly onto the endoscopic image in real time. Research shows VSE significantly improves measurement accuracy compared to conventional methods.

What the research says

A meta-analysis of 11 studies (1581 polyps) found that VSE improved measurement accuracy by about 14.5% over visual assessment and reduced total misclassifications from 73.6% to 54.3% ². In clinical settings, VSE cut overestimation rates nearly in half (22.5% vs. 41.5%) ². A randomized controlled trial reported VSE accuracy of 84% versus 68.4% for visual assessment, and VSE was significantly better at correctly sizing polyps larger than 5 mm ⁵. Another study showed VSE had high agreement with actual polyp size on removed specimens, with a mean bias of only -0.05 mm ⁶. In a preclinical trial, VSE outperformed both biopsy forceps (82.7% vs. 78.9% accuracy) and endoscopic rulers (82.7% vs. 78.4%), and it misclassified far fewer large polyps (≥20 mm) as smaller than 20 mm (8.3% vs. 66.7% for forceps and 75.0% for rulers) ⁷. Network meta-analysis ranked VSE as the top method for minimizing total misclassification ².

What to ask your doctor

• Is Virtual Scale Endoscopy available at your facility for my colonoscopy?
• How does VSE compare to the measurement method you typically use?
• Could more accurate polyp sizing change my surveillance interval or treatment plan?
• Are there any additional costs or limitations associated with using VSE?
• Would VSE be particularly helpful for measuring polyps that are borderline in size (e.g., near 5 mm or 10 mm)?