REVIEW ARTICLE
The Use of Alternate Light Sources in the Clinical Evaluation of Child Abuse and Sexual Assault Bonnie Mackenzie, MD* and Carole Jenny, MD, MBAÞ
Abstract: Alternate light sources are devices that produce visible and invisible light at specific wavelengths to allow for enhanced visualization of fluorescent substances. These devices (which include Wood’s lamp and blue light) are often used in forensics for evidence collection and can be quite useful to physicians in the medical evaluation of suspected physical or sexual assault. An understanding of the proper applications, as well as the limitations, of each alternate light source is imperative to correctly performing and interpreting medical evaluations in the emergency department. This review discusses the evidence from prospective trials in children and adults on the ability of specific alternate light sources to identify evidence of physical or sexual assault and also highlights some promising new technological adjuncts to alternate light sources that may allow for accurate dating of bruising. Key Words: alternate or alternative light source, Wood’s lamp, bruising, sexual assault, child abuse (Pediatr Emer Care 2014;30: 207Y210)
T
he use of alternate light sources (ALSs) in forensic medicine is abundant in the mainstream media. One cannot watch a modern crime television show without seeing images of an investigator using filter goggles and an ALS to determine the presence of an incriminating body fluid that contains the perpetrator’s DNA and thus clinches the case. Although ALS can be useful when properly applied, a fundamental understanding of their applications and limitations is necessary for correct interpretation. This article provides a comprehensive review of the literature surrounding the use of ALS in medical evaluations, with special emphasis on the evaluation of suspected child abuse and sexual assault.
BACKGROUND An ALS refers to a device that produces visible and invisible light at wavelengths specifically chosen to allow or enhance the visualization of particular substances. Visible light is composed of the spectrum of wavelengths from 400 nm (which corresponds with violet light) to 700 nm (red light).1 Above the visible spectrum, at the longer wavelengths of greater than 700 nm, there exists infrared (IR) light, and below the visible spectrum, at the shorter wavelengths of less than 400 nm, there exists UV light. White light contains all the visible wavelengths. Whereas an incandescent light bulb emits only 10% visible light, the remaining 90% of energy is actually IR. Blue light consists mainly of light at a wavelength of 430 to 490 nm. From the Departments of *Emergency Medicine and †Pediatrics, Alpert Medical School of Brown University, Providence, RI. Disclosure: The authors declare no conflict of interest. Reprints: Bonnie Mackenzie, MD, Pediatric Emergency Medicine, 100 York Street, Suite 1F, New Haven, CT 06511 (e
The Use of Alternate Light Sources in the Clinical Evaluation of Child Abuse and Sexual Assault Bonnie Mackenzie, MD* and Carole Jenny, MD, MBAÞ
Abstract: Alternate light sources are devices that produce visible and invisible light at specific wavelengths to allow for enhanced visualization of fluorescent substances. These devices (which include Wood’s lamp and blue light) are often used in forensics for evidence collection and can be quite useful to physicians in the medical evaluation of suspected physical or sexual assault. An understanding of the proper applications, as well as the limitations, of each alternate light source is imperative to correctly performing and interpreting medical evaluations in the emergency department. This review discusses the evidence from prospective trials in children and adults on the ability of specific alternate light sources to identify evidence of physical or sexual assault and also highlights some promising new technological adjuncts to alternate light sources that may allow for accurate dating of bruising. Key Words: alternate or alternative light source, Wood’s lamp, bruising, sexual assault, child abuse (Pediatr Emer Care 2014;30: 207Y210)
T
he use of alternate light sources (ALSs) in forensic medicine is abundant in the mainstream media. One cannot watch a modern crime television show without seeing images of an investigator using filter goggles and an ALS to determine the presence of an incriminating body fluid that contains the perpetrator’s DNA and thus clinches the case. Although ALS can be useful when properly applied, a fundamental understanding of their applications and limitations is necessary for correct interpretation. This article provides a comprehensive review of the literature surrounding the use of ALS in medical evaluations, with special emphasis on the evaluation of suspected child abuse and sexual assault.
BACKGROUND An ALS refers to a device that produces visible and invisible light at wavelengths specifically chosen to allow or enhance the visualization of particular substances. Visible light is composed of the spectrum of wavelengths from 400 nm (which corresponds with violet light) to 700 nm (red light).1 Above the visible spectrum, at the longer wavelengths of greater than 700 nm, there exists infrared (IR) light, and below the visible spectrum, at the shorter wavelengths of less than 400 nm, there exists UV light. White light contains all the visible wavelengths. Whereas an incandescent light bulb emits only 10% visible light, the remaining 90% of energy is actually IR. Blue light consists mainly of light at a wavelength of 430 to 490 nm. From the Departments of *Emergency Medicine and †Pediatrics, Alpert Medical School of Brown University, Providence, RI. Disclosure: The authors declare no conflict of interest. Reprints: Bonnie Mackenzie, MD, Pediatric Emergency Medicine, 100 York Street, Suite 1F, New Haven, CT 06511 (e
