Evaluation of the Effect of Toluidine Blue Dye on the Diagnosis of Anogenital Injuries in Cases Associated with Sexual Assaults Referring to Department of Forensic Medicine Khorasan, Iran

Direct observation of invisible injuries sexual assaults is accompanied by some difficulties. One of the most important solutions to solve these difficulties is using colors, such as toluidine blue, as a discrimination factor. This study aimed to evaluate the effect of toluidine blue coloring techniques to detect anogenital injuries. To this end, a comparison was made between the direct observation technique and the toluidine blue coloring technique.

This descriptive and prospective interventional research was applied to all cases claimed to be assaulted sexually in 2015. Subjects were selected employing the census procedure, and data were collected using a checklist containing demographic characteristics, level of detected injuries, and time elapsed after the abusive event. Data analysis was performed via Excel and SPSS software.

Out of the total number of cases studied in 2015, 40.8% were male and 59.2% were female. In addition, the age ranges of male and female subjects claimed to be assaulted sexually were 8-23 years (14.45±4.2) and 12-52 years (21.9±9.8), respectively. The color effect in the detection of the chafes injuries consequent from the sexual assault were helpful in 37% and 44.7% of vaginal and anal examinations, respectively.

This study showed that the use of toluidine blue in anal examinations is more effective than genital examinations in diagnosing injuries that exist in the form of abrasions and scratches.  The effectiveness of color was correlated with the place of rape, the body size of the rapist, and the time interval between the rape and the examination.