Is Fluorescence Under an Alternate Light Source Sufficient to Accurately Diagnose Subclinical Bruising?

Abstract

This single-blinded, randomized validation study was conducted to evaluate whether fluorescence under alternate light sources (ALS) is sufficient to diagnose subclinical bruising (bruising not visible under white light). Standardized trauma was induced on randomly selected ventral forearms. On days 1, 7, and 14 investigators independently examined case forearms under white light for perceived bruising and under ALS for fluorescence and compared body maps. 56 case and 62 control forearms (n = 118) were examined. Sensitivity of ALS on days 1, 7, and 14 was 76.8%, 69.6%, and 60.7%, respectively, compared to 69.6%, 60.0%, and 32.1% for white light. The specificity of ALS on days 1, 7, and 14 was 51.6%, 59.7%, and 53.2%, respectively, compared to 71.0%, 81.4%, and 86.9% for white light. ALS has increased sensitivity yet low specificity compared to white light in accurately detecting bruises. Fluorescence under ALS is not sufficient to accurately or responsibly diagnose subclinical bruising.

Alternate Light Source Findings of Common Topical Products

“…If absorption is still present post-cleansing, this would be consistent with a positive finding, especially if supported by history or other examination findings such as pain with palpation or induration. However, we agree with the caution previously stated in the literature, that positive ALS findings alone are not definitive of the presence of a bruise or other injury (Lombardi et al, 2015).…”

“…Such limitations may have contributed to their reported false-positives. Lastly, the investigators in that study did not differentiate if ALS findings were darker (consistent with absorption) or brighter (consistent with fluorescence) than the adjacent skin, further complicating interpretation of their findings (Lombardi et al, 2015;Marin & Buszka, 2013).…”

“…A recent randomized, single-blind study improved upon previous ALS research by examining the effectiveness of narrow-band visible and UV alternate light to detect latent bruises intentionally created when a four ounce weight was dropped down a five foot tube onto subjects' ventral forearms (Lombardi et al, 2015). Two weeks post trauma, ALS detected almost twice as many subjects with positive ALS findings versus white light.…”

“…Alternate light and its ability to aid in visualization of sub-dermal bruises, visible and invisible to the naked eye has been examined in a small number of previous studies (Holbrook & Jackson, 2013;Limmen et al, 2013;Lombardi, Canter, Patrick, & Altman, 2015). None of these examined whether commonly used topical products absorb under various wavelengths of light.…”

Alternate Light Source Findings of Common Topical Products

“…During the forensic exam, when ALS demonstrates absorption, it is often assessed as “injury” or “bruising.” A recent randomized, single-blind study improved upon previous ALS research by examining the effectiveness of narrow-band visible and UV alternate light to detect latent bruises intentionally created when a four ounce weight was dropped down a five foot tube onto subjects’ ventral forearms (Lombardi et al, 2015). Two weeks post trauma, ALS detected almost twice as many subjects with positive ALS findings versus white light.…”