Abstract: | The efficacy of autofluorescence imaging (AFI) for assessing ulcerative colitis (UC) activity was reviewed. AFI images of UC lesions could be classified into four categories: green; green with purple spots; purple with green spots; and purple. The strength of purple in AFI images of UC lesions is related to histologic severity, thus this classification is helpful to assess the activity of UC. The autofluorescence of AFI images was also quantified using color analysis software. Active lesions had significantly low autofluorescence/reflex ratio than inactive areas in UC patients. The ratio is inversely proportional to histologic severity. When the cut‐off is 0.9, the accuracy to predict histologic activity by AFI is 92%. |