How to read small bowel capsule endoscopy: a practical guide for everyday use

Abstract

Small bowel (SB) capsule endoscopy (SBCE) is often perceived by both patients and physicians as a "lightweight," noninvasive, comfortable procedure that is easily performed with little more than swallowing a pill and a glass of water. However, "easy to carry out" does not translate to ease of reading or interpretation. A SB capsule acquires thousands of images and generates a long video; however, clinically relevant findings are often seen in only a few frames. There is no way to direct or focus the camera , the capsule's lens cannot be cleaned or luminal debris removed , and perhaps most importantly, the capsule cannot take tissue samples. Therefore, the rate of missed lesions in the SB has been quoted as high as 10 % [1]. Despite various SB imaging modalities offering similar diagnostic yield (DY) and miss rates, SBCE is one of the few endoscopic procedures open to immense scrutiny, as the data recorded are readily accessible for further on-demand review. This may expose clinicians to additional litigation but conversely, also provides a unique learning platform for new generations of SBCE readers. This is certainly fertile ground for virtual artificial neural network (ANN) training systems and even artificial intelligence (AI) diagnosis [2]. Currently, several different SBCE platforms exist. They differ in technical features and specifications such as size and weight, number and position of cameras, frame rate acquisition , and battery duration, as well as in several functions of proprietary reading software. In this editorial, we aim to provide general principles for SBCE reading, which are only partially addressed in recent technical reviews or guidelines [3-9]. We would also like to suggest tips and tricks to reduce common deficiencies in SBCE. Reading capsule endoscopy: when and where The following paragraph describes the SBCE video review process. It is crucial to point out that, as emphasized in several clinical guidelines [3-5, 7-9] this is only one step of a complex diagnostic work-up. Before approaching any SBCE video, it is essential to be aware of clinical details about a patient, such as the duration of the clinical history, comorbidities, medications, and clinical presentation. Knowledge of these data allows for a thorough, focused, and fruitful SBCE revision process. It could be argued that knowing clinical data may introduce an anticipation bias, leading to overestimating the role of this procedure in the diagnostic work-up. However, knowledge of clinical data is crucial for a balanced evaluation of findings and meaningful SBCE conclusion. Although there are obvious variations in anatomy, pathology , patient demographics, and technical specifications for each SBCE model, the capsule generally takes between 1.5 to 4 to 5 hours to cover the entire SB. This generates a video with a long run time and often prolonged sections of normal SB, which requires time, focused attention, and dedication to accurately evaluate and review [6, 10-12]. It is a misconception that SBCE video reading is a simple task that can be undertaken as an activity performed in between other, more compelling clinical duties. In our opinion, SBCE reading should be afforded protected time and be performed as thoroughly and diligently as any other endoscopic activity. Experience can reduce SBCE reading time, however, the time allocated for review of one