IEEE Trans Biomed Eng. 2019 Mar;66(3):632-639. doi: 10.1109/TBME.2018.2852715. Epub 2018 Jul 5.
Clinical endoscopy and colonoscopy are commonly used to investigate and diagnose disorders in the upper gastrointestinal tract and colon, respectively. However, examination of the anatomically remote small bowel with conventional endoscopy is challenging. This and advances in miniaturization led to the development of video capsule endoscopy (VCE) to allow small bowel examination in a noninvasive manner. Available since 2001, current capsule endoscopes are limited to viewing the mucosal surface only due to their reliance on optical imaging. To overcome this limitation with submucosal imaging, work is under way to implement microultrasound (μUS) imaging in the same form as VCE devices. This paper describes two prototype capsules, termed Sonocap and Thermocap, which were developed respectively to assess the quality of μUS imaging and the maximum power consumption that can be tolerated for such a system. The capsules were tested in vivo in the oesophagus and small bowel of porcine models. Results are presented in the form of μUS B-scans as well as safe temperature readings observed up to 100 mW in both biological regions. These results demonstrate that acoustic coupling and μUS imaging can be achieved in vivo in the lumen of the bowel and the maximum power consumption that is possible for miniature μUS systems.
临床内镜和结肠镜检查分别常用于上消化道和结肠疾病的诊断和检查。然而，利用传统内镜检查解剖学上较远的小肠具有挑战性。这种情况以及微型化的进步促使了胶囊内镜的发展，以实现非侵入性的小肠检查。自 2001 年以来，由于依赖光学成像，目前的胶囊内镜仅局限于观察黏膜表面。为了通过黏膜下成像克服这一限制，正在努力在相同的胶囊内镜设备中实现微超声（μUS）成像。本文描述了两个原型胶囊，分别称为 Sonocap 和 Thermocap，它们分别用于评估 μUS 成像的质量和可以耐受的最大系统功率。这些胶囊在猪模型的食管和小肠中进行了体内测试。结果以 μUS B 扫描的形式以及在两个生物区域中观察到的高达 100 mW 的安全温度读数呈现。这些结果表明，在肠腔的管腔内可以实现声学耦合和 μUS 成像，以及微型 μUS 系统可能的最大功率消耗。
