Visentini-Scarzanella Marco, Kawasaki Hiroshi, Furukawa Ryo, Bonino Marco Augusto, Arolfo Simone, Lo Secco Giacomo, Arezzo Alberto, Menciassi Arianna, Dario Paolo, Ciuti Gastone
Department of Information Systems and Biomedical Engineering, Kagoshima University, Japan.
Department of Advanced Information Technology, Kyushu University, Japan.
Endosc Int Open. 2018 May;6(5):E602-E609. doi: 10.1055/a-0577-2798. Epub 2018 May 8.
Polyp size measurement is an important diagnostic step during gastrointestinal endoscopy, and is mainly performed by visual inspection. However, lack of depth perception and objective reference points are acknowledged factors contributing to measurement errors in polyp size. In this paper, we describe the proof-of-concept of a polyp measurement device based on structured light technology for future endoscopes.
Measurement accuracy, time, user confidence, and satisfaction were evaluated for polyp size assessment by (a) visual inspection, (b) open biopsy forceps of known size, (c) ruled snare, and (d) structured light probe, for a total of 392 independent polyp measurements in ex vivo porcine stomachs.
Visual assessment resulted in a median estimation error of 2.2 mm, IQR = 2.6 mm. The proposed probe can reduce the error to 1.5 mm, IQR = 1.67 mm ( = 0.002, 95 %CI) and its performance was found to be statistically similar to using forceps for reference ( = 0.81, 95 %CI) or ruled snare ( = 0.99, 95 %CI), while not occluding the tool channel. Timing performance with the probe was measured to be on average 54.75 seconds per polyp. This was significantly slower than visual assessment (20.7 seconds per polyp, = 0.005, 95 %CI) but not significantly different from using a snare (68.5 seconds per polyp, = 0.73, 95 %CI). However, the probe's timing performance was partly due to lens cleaning problems in our preliminary design. Reported average satisfaction on a 0 - 10 range was highest for the proposed probe (7.92), visual assessment (7.01), and reference forceps (7.82), while significantly lower for snare users with a score of 4.42 ( = 0.035, 95 %CI).
The common practice of visual assessment of polyp size was found to be significantly less accurate than tool-based assessment, but easy to carry out. The proposed technology offers an accuracy on par with using a reference tool or ruled snare with the same satisfaction levels of visual assessment and without occluding the tool channel. Further study will improve the design to reduce the operating time by integrating the probe within the scope tip.
息肉大小测量是胃肠内镜检查中的重要诊断步骤，主要通过目视检查进行。然而，缺乏深度感知和客观参考点是导致息肉大小测量误差的公认因素。在本文中，我们描述了一种基于结构光技术的息肉测量装置用于未来内镜的概念验证。
通过以下方式评估息肉大小评估的测量准确性、时间、用户信心和满意度：(a)目视检查、(b)已知尺寸的开放式活检钳、(c)带刻度圈套器和(d)结构光探头，在离体猪胃中总共进行了392次独立的息肉测量。
目视评估的中位估计误差为2.2毫米，四分位距=2.6毫米。所提出的探头可将误差降低至1.5毫米，四分位距=1.67毫米（P=0.002，95%置信区间），其性能在统计学上与使用活检钳作为参考（P=0.81，95%置信区间）或带刻度圈套器（P=0.99，95%置信区间）相似，同时不会堵塞器械通道。使用探头的计时性能测量为每个息肉平均54.75秒。这明显慢于目视评估（每个息肉20.7秒，P=0.005，95%置信区间），但与使用圈套器无显著差异（每个息肉68.5秒，P=0.73，95%置信区间）。然而，探头的计时性能部分归因于我们初步设计中的镜头清洁问题。在所提出的探头（7.92）、目视评估（7.01）和参考活检钳（7.82）方面，报告的0至10分范围内的平均满意度最高，而圈套器使用者的满意度显著较低，得分为4.42（P=0.035，95%置信区间）。
发现息肉大小的目视评估这一常见做法比基于工具的评估准确性明显更低，但易于实施。所提出的技术提供的准确性与使用参考工具或带刻度圈套器相当，具有与目视评估相同的满意度水平，且不会堵塞器械通道。进一步的研究将改进设计，通过将探头集成到内镜尖端来减少操作时间。
