| Theme | The Latest Frontier of Endoscopy | |
|---|---|---|
| Title | Transition & Progress of Efforts to Change Illumination Color Spectrum | |
| Publish Date | 2006/01 | |
| Author | Hirohumi Niwa | St. Marianna University School of Medicine |
| [ Summary ] | It is often mistakenly believed that the mucosal surface of the stomach or colon has unique color phases, driving many researchers to conduct studies from that point of view. However, objects actually do not have their own unique color phases except for ones that emit light themselves because types of light sources determine the visible color phases of objects. In short, the type of illumination light source must be taken into consideration when the color phases of the mucosal surface are to be discussed. Furthermore, if the color spectrum of the light source is varied, elements of colors are changed, including the color of the mucosal surface, different depths of light penetration into the mucosa, degree of reflection, etc. This means that if observation is carried out under light produced in a specially tuned illumination spectrum, it will provide unique findings that cannot be obtained through other light spectrum patterns. Narrow band imaging (NBI) has been drawing a great deal of attention. It is a technology enabled by utilization of short to medium wavelengths by applying different filters to light. It has been gradually put into use to utilize different depths of penetration rates for different color band ranges and to obtain special imaging effects by applying false color enhancement. Attempts to obtain special effects with varying spectrums of light are new. However, many experiments have been done since the time of the introduction of gastrocameras. Reports have shown the ability of ultraviolet ray gastrocameras to vividly image of lesions on the mucosal surface, outlines of IIc, sessesion of folds at the rim of IIc, etc. There have also been experiments to acquire special findings by observing infrared rays in red images by using infrared film and removing the blue spectrum. Use of fluorescent gastrocameras has been also studied. In this paper, several examples of those attempts to acquire special effects by changing color band ranges of light are introduced. Variances of findings depending on differences in illumination light for routine endoscopy are also studied. |
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