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Skeletal remains often have missing mandibles owing to the environment in which the corpse was placed or damage caused by an animal. Loss of the mandible reduces the accuracy of skull identification. Although several studies have validated methods for estimating mandibular morphology from conventional anthropological measurements using skull specimens, there are no reports using three-dimensional computed tomography (3DCT) images. Here, we examined methods for establishing the mandibular morphology from the remaining skulls using postmortem computed tomography (PMCT) images. We used PMCT images from 200 Japanese subjects as samples. After verifying the morphological correlation between the cranium and mandible, we created and validated estimation models using multiple regression analysis (stepwise method) for seven sites that were necessary for understanding the morphology of the mandible. Among the regression models, the estimated model for bicondylar breadth had the highest coefficient of determination (adjR 2  = 0.53). We verified the accuracy of the model on a sample independent from the specimen used to create the estimation model and found that the formulated model of bicondylar breadth had good estimation accuracy, with a high correlation coefficient between the measured and predicted values of 0.82 and a mean absolute error of 3.582 mm, indicating that the model had good estimation accuracy. Here, we established a novel method for estimating the missing mandibular morphology based on PMCT data from the Japanese population. Our estimation model can help determine the missing mandibular morphology in a cranium remnant., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Analyzing the way of deposition of saliva stains contributes to appropriate interpretation of saliva as evidence in court, particularly in sexual assault cases. In this proof-of-concept study, we aimed to confirm the difference between drooling-derived (non-contact) saliva and licking-derived (contact) saliva and clarify whether objectively distinguishing between the two saliva is possible. To allow discrimination between these two samples, an indicator was devised where the relative Streptococcus salivarius DNA quantity was calculated by dividing the S. salivarius DNA copies by the amount of stained saliva from the same saliva sample using quantitative polymerase chain reaction and salivary α-amylase activity assays. The study findings reveal that the value of the proposed indicator of licking-derived saliva was 100-fold significantly greater than that of drooling-derived saliva (P < 0.05, Welch's t-test). However, theoretical and technical challenges preclude the application of this indicator as a practical method. We believe that this saliva-specific bacterial DNA-based approach could allow estimation of the saliva stain deposition method., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The effects on oral tissues of asphyxiation caused by cervical compression were investigated in 203 rabbits by Kiyotoshi Kato, who published four papers in classical Japanese in Kokubyo Gakkai Zasshi (now The Journal of the Stomatological Society, Japan) in 1941. The aim of this review is to summarize and disseminate the enormous amount of experimental data (reprint permission in English has been obtained from the journal). Based on the experimental models of hanging, strangulation with an external force equal to body weight, and strangulation with an external force equal to 1/10th body weight, the macroscopic and histological findings of the oral region immediately after death, including the respiratory condition until death and ocular conjunctival petechiae, were obtained and compared with 4 cases of human strangulation. Strangulation after each of four physical conditions (anesthesia, starvation, alcohol intake, and bleeding) was also investigated. Experiments were performed to investigate the effects of tracheal obstruction, cervical vein ligation, common carotid artery ligation, cervical nerve amputation, or combinations thereof. In the discussion focusing solely on tooth discoloration, it was suggested that the presence of pink teeth at a stage when putrefaction has little or no effect might be a finding indicative of death from asphyxiation caused by cervical compression. This review provides detailed data on the condition of oral tissues after asphyxiation caused by cervical compression and is expected to be used not only for elucidating the mechanism of the pink teeth phenomenon but also for conducting other forensic research., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Amino acid racemization of dentin (AAR) is among the most precise methods for age estimation in unidentified adult cadavers. Although vital teeth are generally used for this technique, cases often have endodontically treated (Endo) teeth only. Therefore, the aim of this preliminary pilot study was to determine the applicability of Endo teeth by comparing AAR rates between vital and Endo teeth. Thirty-six dentin samples from vital teeth and 18 dentin samples from Endo teeth were analyzed, including the maxillary first premolar, maxillary second molar, and mandibular second premolar. Standard calibration curves for the mandibular second premolar and maxillary second molar were compared among vital teeth, Endo teeth, and mixed vital/Endo teeth. Discrepancies between estimated and actual ages were assessed by analyzing the AAR rates for the maxillary first premolar between vital and Endo teeth. The AAR rates for Endo teeth were higher than those for vital teeth in both the mandibular second premolar and maxillary second molar, and the correlation of the standard calibration curve for vital teeth only was highest (r = 0.982836; r = 0.92011467), followed by mixed (r = 0.949579; r = 0.76158) and Endo teeth only (r = 0.896082; r = 0.744991). In the maxillary first premolar, discrepancies were more than 10 years for all 5 Endo teeth, based on the standard calibration curve of vital teeth. The present study suggests that the AAR rates for Endo teeth might be affected by variation in dentin structure between vital and Endo teeth., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Body fluid identification from crime scene evidence is an essential procedure in forensic investigations. Among various procedures, multiplex reverse transcription PCR assays have a clear advantage over conventional methods because different types of body fluids can be analyzed simultaneously. For more precise, comprehensive, and objective identification of forensically relevant body fluids, 15 target genes for blood, saliva, semen, vaginal fluid, and nasal secretion were selected; their primers were re-designed and multiplex PCR conditions were optimized to prioritize specificity for those body fluids. Multiple amplicons were separated and determined by the SeqStudio Genetic Analyzer with an all-in-one and easy-to-use cartridge. Then, the cutoff value was set for each marker to eliminate the detection of slight amplification in non-targeted body fluids. As a result, the targeted body fluid specificities of the developed procedure were drastically improved. Although successful determination of the target gene depends on sample condition and marker sensitivity, our procedure was applicable for the precise determination of body fluids in mixed body fluid stains, aged samples, and various mock casework samples. Therefore, it could be a powerful and convenient tool for the precise identification of multiple body fluids in forensic laboratories., (Copyright © 2022 Elsevier B.V. All rights reserved.)

On the battlefields of Syria, many innocent civilians have been killed or injured by sarin poisoning. In Malaysia in February 2017, a North Korean man was assassinated with VX at Kuala Lumpur International Airport. In the face of such threats, a more effective antidote against organophosphonate acetylcholinesterase (AChE) inhibitors is needed, one that can freely penetrate into the central nervous system (CNS) through the blood-brain barrier (BBB). In the 1995 Tokyo subway sarin attack, which produced more than 6,000 victims, 2-pyridinealdoxime methiodide was the most commonly used antidote in hospitals, but it was unable to prevent CNS damage and no other oximes have been approved for use in Japan. Ultimately, 12 people died, and many victims had severe neurological injuries or sequelae. Although more than 25 years have passed since the incident, progress has been slow in the development of a new antidote that can penetrate the BBB, restore AChE activity in the CNS, and definitely prevent brain injury. From the perspectives of countering terrorism and protecting innocent people from nerve agent attacks, the search for nerve agent antidotes should be accelerated with the goals of improving both survival and quality of life. This review gives an overview of a series of our studies on the development of a new antidote since the Tokyo subway sarin attack and emphasizes that there is unfortunately still no promising antidote for saving the CNS in Japan., (Copyright © 2020 Elsevier B.V. All rights reserved.)

An evaluation of a Rapid DNA system was performed using buccal swab samples and mock Disaster Victim Identification (DVI) samples collected postmortem. The allelic ladder success rate was 90% and samples analyzed simultaneously with this allelic ladder were used for further analysis. Sample success rate of the Rapid DNA system for buccal swab samples, and blood and muscle DVI samples were calculated. Success rates of buccal swab samples were 100% and 75% using cassettes preloaded with all reagents suitable for high- and low-DNA content samples, respectively. Success rates of fresh DVI samples were 80% to 100%. Success rates of putrefied DVI samples varied widely between 0% and 20% and 50% to 80% depending on cassette and sample types. Conventional DNA analysis was performed for comparison with the results of the Rapid DNA system. DNA quantity and degradation of human DNA were measured using quantitative polymerase chain reaction. DVI samples that yielded more than 1 ng/µL of DNA when extracted with conventional protocols were suitable for analysis using cassettes for both high- and low-DNA content samples. DVI samples with less than 0.1 ng/µL of DNA were suitable only for analysis using cassettes for low-DNA content samples. All alleles called and exported by the Expert system software implemented in the Rapid DNA system were concordant with allele calls made by conventional capillary electrophoresis DNA analysis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The identification of vaginal fluid from casework samples of sexual assaults provides important probative evidence of vaginal intercourse. The aim of this study was to establish a more specific procedure for identifying vaginal fluids for forensic purposes. Vaginal fluid marker candidates have been evaluated quantitatively and five of these markers (ESR1, SERPINB13, KLK13, CYP2B7P1, MUC4) have been amplified simultaneously by a multiplex reverse transcription-polymerase chain reaction (RT-PCR) procedure. Each amplicon has been separated and quantified automatically using chip electrophoresis. Subsequently, in the present study, detectability and cross-reactivity of the developed multiplex procedure were assessed in detail using various forensically relevant body fluids. Then, a cutoff value for the positive detection of vaginal fluids was set for each marker by Youden index. The ability of the multiplex RT-PCR assay to distinguish between vaginal and other body fluids was evaluated statistically using a likelihood ratio (LR) that was estimated using a Bayesian estimation approach to consider the infrequency of detection. A high LR was obtained when all five markers showed positive results (LR = 4.33 × 10 9 ; 95% credible interval, 3.95 × 10 7  -2.87 × 10 12 ). The developed procedure was validated using vaginal fluid samples under various conditions. High LRs were found for aged vaginal fluid stains, although each amplicon peak was low. It was also able to identify vaginal stains mixed with other body fluids. In conclusion, the multiplex RT-PCR-based procedure followed by the statistical evaluation using LR could be a powerful tool for the objective identification of vaginal fluids., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Age estimation in adults based on aspartic acid racemization (AAR) provides fewer errors and higher precision than that based on bone morphology for the identification of cadavers. The technique has been established in some labs as a routine method. However, as the essential requisites for the technique, a wide age range of teeth of the same type as the target tooth must be collected for calibration for each examination. We investigated whether dentin standard samples could be prepared by increasing the AAR rate via heat. Powdered dentin was prepared from a maxillary first premolar (13 years) and heated for 0-72 h at 110 °C. The extent of AAR increased significantly with heating time and the correlation was strong (r = 0.913; p < 0.01). Similar results were found for a mandibular canine (24 years, r = 0.948; p < 0.01) and a maxillary third molar (20 years, r = 0.944; p < 0.01). We attempted to estimate the age of four maxillary first premolars of persons aged 25-58 years by using the heated samples (18 years, 12 h to 7 days). The differences between the actual and estimated ages were within ±5 years. The stability of the AAR rates in the powdered dentin during storage at 22-25 °C, 4 °C, and -30 °C was examined after 1 year and no significant changes had occurred. We were able to prepare dentin standard samples and created a calibration curve. This is a pilot study that needs to be validated before it can be used in forensic practice., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The source of small amounts of touch DNA, which is transferred from the skin to an object when it is handled or touched, could be an issue in the forensic analysis of criminal cases. Here, we performed an extended evaluation of skin- or sweat-characteristic mRNAs to investigate their usability to infer whether an object has been handled or touched by someone. First, we compared the expression levels of candidate genes between skin swabs and other body fluids by quantitative RT-PCR analysis. Among the analyzed genes, corneodesmosin (CDSN), late cornified envelope 1C (LCE1C), filaggrin (FLG), desmocollin 1, and dermcidin were selected for further analysis on the basis of their specificities and sensitivities. Then, we tried to detect these genes from mock casework samples. As a result, CDSN, LCE1C, and FLG could be good markers because of their detectability. Finally, we determined the correlation between the expression of these genes and DNA yield of skin swabs to assess their adaptability as a screening test for touch DNA samples. However, the detectability of these genes was not correlated with the DNA yield of skin swab samples. In conclusion, gene expression analysis of the skin- or sweat-characteristic mRNAs CDSN, LCE1C, and FLG could be useful for inferring the skin origin of touched contact traces, but the use of the expression levels of these mRNAs for the prediction of DNA yield is problematic. To develop a screening test for touch DNA samples, other markers that have a well-correlated sensitivity with DNA analysis should be investigated., (Copyright © 2018. Published by Elsevier B.V.)

The identification of blood samples obtained from crime scenes has been an important step in forensic investigation. Recently, a novel approach using the blood-specific methylated CpG site cg06379435 has been reported. In this study, we developed a real-time polymerase-chain-reaction-based method that can simply and rapidly quantitate the methylation ratio of cg06379435 and its neighboring CpGs and set the threshold ratios for blood identification by analyzing various body fluid samples. Blood identification using the thresholds was successfully performed in the analysis of a small amount (1ng) of DNA from blood and various aged blood samples, including 29-year-old stains. We also demonstrated a test for allele-specific blood identification from a mixed DNA sample by bisulfite sequencing analysis of these CpG sites and their neighboring single nucleotide polymorphism, rs7359943 (A/G), which is of relevance in cases where mixed samples are obtained from crime scenes. The stability of DNA methylation in aged samples and the usefulness of neighboring genetic information shown in this study suggest that DNA-methylation-based body fluid identification will play a major role in future forensic investigations., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Body fluid identification and individual identification are an important series of tests in usual criminal investigations. Recent reports have demonstrated a new approach using DNA/RNA co-extraction methods in which RNA for body fluid identification and DNA for short tandem repeat (STR) typing are extracted simultaneously from the same sample. This study evaluated a standard co-extraction kit, the AllPrep® DNA/RNA Mini Kit, in order to demonstrate the availability of the co-extraction procedure for those real-time polymerase chain reaction-based body fluid identification methods that we have validated previously. We demonstrated that the use of the Allprep Kit, for which we adjusted the lysis temperature to 56°C to improve extraction efficiency, can simultaneously extract sufficient RNA and DNA for body fluid identification and STR analysis; however, a longer incubation at a high temperature slightly affected the ΔCt value of each target gene and appeared to be not as effective for DNA extraction from old stains as from 1-day-old stains. This method is promising for future forensic investigations because the use of this kit can reduce sample consumption for body fluid identification and DNA typing., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

ABO typing is effective in several forensic investigations, including the identification of unknown cadavers. When the serological method cannot be used because of the decomposition of ABH antigens, ABO genotyping of DNA is often performed. Previously, we reported a novel ABO genotyping method using a DNA chip as a proof of concept. This chip can simultaneously detect single nucleotide polymorphisms in the ABO gene and a part of the primate-specific D17Z1 sequence for human identification. In the present study, this method was modified and further validated for forensic use. We demonstrated that the modified method can correctly perform ABO genotyping and human identification if the appropriate amount of template (>0.5ng of DNA) is analyzed. Moreover, it was found that this chip method can be used to type highly degraded DNA. This method is expected to be a useful supplemental tool for the identification of individuals from highly decomposed samples., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

A new approach for the identification of body fluid stains by comparing specific mRNA expression levels has been extensively studied in recent years. Here, we examine whether nasal blood, which is regarded as one of the most difficult types of blood to identify, can be identified by comparing mRNA expression levels of target genes specific to saliva, nasal secretion, and blood. The saliva-specific statherin gene (STATH) was found to be expressed at high levels in not only saliva (dCt value: 1.32±1.39, n=5), but also nasal secretions (dCt value: 0.90±1.14, n=5), while the histatin gene (HTN3) was only expressed at high levels in saliva (dCt value: 1.08±2.35, n=5). We also confirmed that the hemoglobin-beta gene (HBB) showed high expression levels in blood (dCt value: -9.51±0.40, n=5). Four nasal blood stains were found to highly express STATH (dCt value: 5.65±3.98) and HBB (dCt value: -8.79±1.67) but not HTN3, suggesting that the stain samples contained both nasal secretions and blood and can therefore be identified as nasal blood stains. Although menstrual blood showed the same expression pattern as nasal blood, the menstrual blood-specific protein matrix metallopeptidase 7 (MMP7) was not expressed in all nasal blood stain samples. Therefore, its expression levels could be used to discriminate between nasal and menstrual blood. In conclusion, real-time RT-PCR was able to identify nasal blood, although the stability of gene expression in nasal blood stains was low over time, suggesting that this assay may not be effective for older stains. Future work should examine the usefulness of this assay under various environmental conditions., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

In criminal investigations, usually it is necessary to identify whether blood spots found at crime scenes are from humans or not. Nowadays, immunohistochemical methods and DNA analysis are usually used for this purpose. However, such methods and DNA analysis are labor intensive and expensive, and require highly trained skilled technicians. Recently, the genome profiling method (GP method) was developed. However, its use as a human DNA analysis method has not been reported. In this report, an attempt was made to differentiate human blood samples from animal blood samples using the GP method for forensic purposes. DNA extracted from a rat, squirrel, cat, dog, cow, and antelope along with human blood samples were analyzed. Following cluster analysis the human samples clustered into a single group separate from the animal samples. Therefore, although the number of samples was small the results suggest that the GP method might enable us to differentiate human samples from various animal samples. It may become a powerful tool in the field of forensic science., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

To preliminarily evaluate the applicability of bacterial DNA as a marker for the forensic identification of vaginal fluid, we developed and performed PCR-based detection of 16S ribosomal RNA genes of Lactobacillus spp. dominating the vagina and of bacterial vaginosis-related bacteria from DNA extracted from body fluids and stains. As a result, 16S ribosomal RNA genes of Lactobacillus crispatus, Lactobacillus jensenii and Atopobium vaginae were specifically detected in vaginal fluid and female urine samples. Bacterial genes detected in female urine might have originated from contaminated vaginal fluid. In addition, those of Lactobacillus iners, Lactobacillus gasseri and Gardnerella vaginalis were also detected in non-vaginal body fluids such as semen. Because bacterial genes were successfully amplified in DNA samples extracted by using the general procedure for animal tissues without any optional treatments, DNA samples prepared for the identification of vaginal fluid can also be used for personal identification. In conclusion, 16S ribosomal RNA genes of L. crispatus, L. jensenii and A. vaginae could be effective markers for forensic identification of vaginal fluid., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

The identification of menstrual blood is important when discriminating menstruation from vaginal trauma in sexual assault cases. The aim of this study was to evaluate two fibrin-fibrinogen degradation product (FDP)-latex agglutination test kits, FDPL® Test (FDP-L) and FDP Plasma "RD" (FDP-P), for their ability to forensically identify menstrual blood. Sensitivity and specificity of the two kits were compared for menstrual blood and various body fluids, and the sensitivity of the FDP-latex agglutination test kit was also compared with that of an immunochromatographic test for human hemoglobin. The robustness of the FDP-latex agglutination test was compared with that of gene expression analysis of menstrual blood specific markers. The FDP-L kit was more sensitive than the FDP-P kit, but it cross-reacted with peripheral bloodstains from healthy volunteers. The FDP-P kit was specific for menstrual blood, with the exception of postmortem blood samples, and was not affected by other body fluids. In an FDP-negative menstrual blood sample, the sensitivity of human hemoglobin detection was lower than for FDP-positive samples and peripheral blood stains, suggesting that determination of human hemoglobin could be useful in interpreting negative results in the FDP-latex agglutination test. In menstrual blood samples incubated in wet conditions, FDP was found to be a robust marker in the identification of menstrual blood compared with mRNA markers. FDP-P testing was shown to be a suitable and highly efficient rapid screening test for the laboratory identification of menstrual blood., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Nasal secretion has been regarded as one of the most difficult body fluids to identify and is especially difficult to discriminate from vaginal secretions and saliva. At present, few specific markers are known for nasal secretions. The aim of this study is to find a new approach for the identification of nasal secretions. We examined expression levels of statherin and histatin, peptides which are commonly found in saliva, in nasal and vaginal secretions by real-time RT-PCR and ELISA assays. Statherin mRNA was highly expressed in all nasal samples (dCt value=-1.49±1.10, n=8) and was detected even in 1-day-old 0.1-μL stains. However, the stability of mRNA in nasal stains was significantly (P<0.01) lower than in saliva. Low levels of statherin mRNA were detected in 4 of the 17 vaginal samples (dCt value=11.65-14.72). Histatin mRNA was not detected in any nasal or vaginal samples, although it was highly expressed in all saliva samples. ELISA assays with anti-statherin goat polyclonal antibody showed that statherin peptide was detected in all nasal and saliva samples even after dilution of more than 1000-fold. The statherin peptide was not detected in any vaginal samples, including samples that expressed low levels of statherin mRNA. The amount of statherin peptide in vaginal samples might be less than the limit of detection of this assay. In the present study, statherin was highly expressed in nasal secretions, but histatin was not. These markers may be useful for discriminating nasal secretions from vaginal secretions and saliva. However, the usefulness of these markers in practical forensic case samples has not yet been examined. Therefore, further research is required to establish the utility of these assays for identification of nasal secretions., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

The identification of sperm at the scene of a sexual crime is important evidence that can be used to prove that a crime took place. We used the new genome profiling (GP) method in this study to identify sperm and vaginal fluid from RNA extracted from bodily fluids. We randomly amplified genes via a PCR approach from these semen and vaginal fluid samples and performed temperature gradient gel electrophoresis between 15-65°C. We identified specific species identification dots (spiddos) for semen and vaginal fluid. The results showed that the GP method is effective for the identification of bodily fluids at the scene of a sex crime., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Multiplex mRNA profiling by a reverse transcription-polymerase chain reaction (RT-PCR) has been reported in the last few years as a new approach for the identification of body fluids. We have also demonstrated the feasibility of identifying body fluids by using a real-time RT-PCR assay. Statherin (STATH) and histatin (HTN3), the selected genes for saliva, and protamin 2 (PRM2) and semenogelin 1 (SEMG1), those selected for semen, showed high specificity to these body fluids. Thus, the sensitivity and specificity of target genes were examined in body fluid stains. All target genes were detected in 0.1 microL 6-day-old stains, and showed high specificity in 7-day-old 30 microL stains. Furthermore, the stability of HTN3 in saliva stains was examined under various environmental conditions over time. The results showed that the degradation of mRNA in the stains was highly affected by wet conditions, and that light was also an important factor. However, mRNA was detectable in an older saliva stain (6 years old) and in an older semen stain (3.5 years old), both of which had been kept under dry and dark conditions. The stability of mRNA beyond our supposition may play an important role in developing new techniques for body fluid identification.

A 40-year-old man experienced cardiopulmonary arrest after intramuscular injection of 20 mg of butylscopolamine bromide. No pathological changes were found at autopsy, and 1.19 microg/mL of butylscopolamine bromide was detected in his serum. Since he had taken no other drugs, his severe symptoms were thought to have been caused by an anaphylactic reaction to butylscopolamine bromide. Butylscopolamine bromide has been used for many years worldwide, and is considered to be a safe drug, with no reports of severe side effects following intramuscular injection. Since an anaphylactic reaction may not be related to a particular medication, the possibility of such a severe reaction must be considered, even during administration of an ostensibly safe drug such as butylscopolamine bromide.

A corpse completely converted into adipocere and showing two adjacent bone defects--a typical gunshot entrance wound and a keyhole lesion--is reported. Postmortem changes, a comminuted fracture of the cranial base, and destruction of the bullets made it impossible to determine the direction of fire through the keyhole lesion. Gunshot wounds may show various atypical forms, including keyhole lesions, and especially in old corpses, the distinction between an entrance wound and an exit wound can be very difficult, even if a careful complete autopsy is performed.