Chromatic distortion during angioscopy: Assessment and correction by quantitative colorimetric angioscopic analysis

Detection and Treatment of Vulnerable Plaques and Vulnerable Patients

“…155 Because visual assessment of yellow is subjective and affected by multiple variables, efforts are being made to develop quantitative colorimetry systems. 145,156,157 Not all sites that are yellow by angioscopy are associated with acute coronary syndromes. Yellow plaque frequently occurs at nonculprit sites in patients with acute MI, 158 and yellow plaques not associated with thrombosis occur in 50% to 60% of patients with stable angina.…”

Quantitative colorimetry of atherosclerotic plaque using the L*a*b* color space during angioscopy for the detection of lipid cores underneath thin fibrous caps

“…Another study also showed the possible effect of the POI within the field of view [9] (i.e., center of the image versus edge), because of a light diffuser at the tip of the angioscope to reduce illumination to the edge in comparison to the center. Therefore, we explored whether adjusting brightness L* can overcome the variations in the perception of color.…”

“…Reproducibility of color measurement in an artificial plaque model When analyzing color in vivo, there are also variables affecting the perception of color, such as variability between each angioscope and white balancing [9]. Therefore, to test for such variables in each ''plaque'', imaging was performed five times using a different angioscope with white balancing each time.…”

“…Lehmann et al [9] studied quantitative colorimetry during angioscopy using two color coordinates and HSI (hue, saturation, intensity) color space (see http://www.en.wikipedia.org/wiki/ HSL_color_space), and utilized it to differentiate thrombus based on color [10]. However, this system was not used to distinguish atherosclerotic plaques, which have a different range of color from thrombus.…”

High‐Resolution Optical Imaging in Interventional Cardiology

“…Due to the fact that several factors can affect color perception during angioscopy, such as the intensity of light, imaging angle, and distance [5,6], a quantitative colorimetric method of measuring coronary plaque color after proper adjustment for brightness has been developed [7]. This method overcomes the effects of these variables and eliminates the subjective element of visual color assessment.…”