Novel image-enhanced endoscopy with i-scan technology

Abstract

i-scan technology is the newly developed image-enhanced endoscopy technology from PENTAX, Japan. This consists of three types of algorithms: surface enhancement (SE), contrast enhancement (CE), and tone enhancement (TE). SE enhances light-dark contrast by obtaining luminance intensity data for each pixel and applying an algorithm that allows detailed observation of a mucosal surface structure. CE digitally adds blue color in relatively dark areas, by obtaining luminance intensity data for each pixel and applying an algorithm that allows detailed observation of subtle irregularities around the surface. Both enhancement functions work in real time without impairing the original color of the organ, therefore, SE and CE are suitable for screening endoscopy to detect gastrointestinal tumors at an early stage. TE dissects and analyzes the individual RGB components of a normal image. The algorithm then alters the color frequencies of each component and recombines the components to a single, new color image. This is designed to enhance minute mucosal structures and subtle changes in color. TE works in real time and consists of three modes such as TE-g for gastric tumors, TE-c for colonic tumors, and TE-e for esophageal tumors. TE is suitable mainly for detailed examination of the lesions that are detected in a screening endoscopy. i-scan technology leads us to easier detection, diagnosis and treatment of gastrointestinal diseases.

Figures

Figure 1

Principle of surface enhancement (SE). A: Enhancement of the edge; B: Enhancement of the minute structure.

Figure 2

Images using SE and contrast enhancement (CE). A: Conventional image; B: SE image; C: CE image; D: SE + CE image.

Figure 3

Principle of CE. A: Enhancement of the low luminance area; B: Relative enhancement of the B component.

Figure 4

Principle of tone enhancement (A) and tone curve (B). TE: Tone enhancement.

Figure 5

Tone curve. A: TE-e; B:TE-g; C:TE-c.

Figure 6

Case 1 (esophageal cancer). A: Conventional image: A slightly reddish irregular area was recognized in the right wall of the thoracic middle esophagus; B: SE + CE image: As compared with conventional image, the lesion could be recognized as an irregular area with clear boundaries; C and D: TE-e image: As compared with conventional image and SE + CE image, the demarcation line of the lesion could be recognized more clearly as a reddish irregular area. This was pathologically diagnosed as carcinoma in situ that corresponded to this region.

Figure 7

Case 2 (gastric cancer). A: Conventional image: A red depressed lesions was visible on the anterior wall of the lower gastric body, but it was difficult to identify the demarcation of it; B: SE + CE image: The differences of the mucosal structure and color of the lesion could be observed; C, D: TE image: The demarcation of the lesion could be identified more clearly, observing changes in mucosal structure and color tone; E: Pathological diagnosis indicated a well to moderately differentiated adenocarcinoma, localized in the mucosal layer.