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Evaluation of a Novel Fluorescent Dye To Detect Ano-genital Injury in Women of Color

NCJ Number
Date Published
March 2017
16 pages

This study sought to identify and test a fluorescent dye that will effectively and visibly stain ano-genital tears and abrasions to improve visibility on dark-skinned individuals, given that the use of toluidine blue (TB) to stain such injuries on white skin is not readily visible on dark skin.


A fluorescent stain would be visible regardless of the surrounding skin color through the use of an alternative light source (ALS). The study findings suggest that fluorescein (FL) is both safe and feasible to use in detecting genital injury in sexual assault victims across all skin tones, including dark skin. A 1-percent solution of FL visualized under blue light was equally effective as TB in enabling the accurate identification of injuries by blinded observers in the murine (rodent) studies and was effective for visualization of genital injuries in women after consensual intercourse in the human study, although the very small number of injuries precluded drawing a firm conclusion about the efficacy of the dye. FL did not delay wound healing in either the murine or human study. It was not associated with any safety concerns in the human study. Implementation of this technique for injury documentation in the clinical exam room will require, in addition to a single lens reflex camera, the availability of a blue light for illuminating the wound and a yellow filter. Both these items are widely available for less than $50, and there is no anticipation that these additional expenses are barriers to the use of FL in the clinical exam for those forensic examiners already using a camera that allows use of a filter. 23 references

Date Published: March 1, 2017