Characterization of Blue Light Imaging for Early Cancer Detection: Validation and in Vivo Feasibility Study

The timely detection of gastrointestinal cancer (GI) is crucial for effective treatment, and endoscopy plays a crucial role in visualising the internal organs for abnormalities. Despite its utility, detecting polyps or early-stage cancer remains a challenge due to their subtle nature, often requiring subjective assessment by experienced clinicians. The introduction of Blue-Light Imaging (BLI) has emerged as a promising solution, accentuating structural tissues and abnormal growths. It uses the principle of light-tissue interaction to enhance the visualisation of the surface microvessels to localise the cancer. However, there are no quantitative studies that suggest a ratio of White:Blue light for visualising these structures with high contrast. In this paper, we comprehensively evaluate different ratios of White:Blue light intensity that can be used for enhanced endoscopic examinations. A gastroscope equipped with BLI technology was engineered, and experiments were carried out to assess the qualitative and quantitative performance of the images taken with different White:Blue light ratios. The system design, in vivo validation on the lower lip mucosa, and in vivo feasibility via pilot human study assessments are discussed. Analysis of our results suggests that mixing White:Blue in the ratio of 1:1 to 4:1 can provide a well-illuminated and high-contrast image. The findings from this study can help design and develop newer BLI systems to improve cancer diagnostics.