An assessment of the Henssge method for forensic death time estimation in the early post-mortem interval.

BACKGROUND: Time-since-death (TSD) diagnostics are crucial in forensic medical casework. The compound method by Henssge and Madea, which combines temperature and non-temperature-based techniques, is widely used to estimate TSD. This study aims to validate the predictive ability of this method in a cohort of 76 deceased individuals with known times of death (TOD). METHODS: A convenience sample of 76 deceased individuals was examined at the Institute of Legal Medicine, University Medical Center Hamburg-Eppendorf. The study included individuals who died at the hospital and those with sudden death in public. Exclusion criteria included age under 18, known infection or sepsis, polytrauma, bleeding, and hyperthermia. The TSD interval was calculated using the Deathtime software. RESULTS: The overall agreement between the actual TOD and the 95% prediction interval for the TSD was 36.8% (95% CI: 26.1 to 48.7). Warm-stored corpses showed a higher agreement (61.9% [95% CI: 38.4 to 81.9]) compared to cold-stored corpses (27.3% [95% CI: 16.1 to 41.0]). Factors such as body mass index (BMI) and body surface area (BSA) were found to influence the odds of agreement. Assuming a plausible range of ambient temperatures between death and admission improved the agreement in cold-stored cases. CONCLUSION: The study found low to moderate agreement between the actual TOD and the 95% prediction interval using the Henssge method. Incorporating BMI and BSA could improve the predictive accuracy of TSD estimations. Further research with larger sample sizes and external validation is recommended to refine the model.

Possibility of drug-distribution measurement in the hair of drowned bodies: evaluation of drug stability in water-soaked hair using micro-segmental analysis.

In postmortem examinations, the drug analysis of hair is effective for revealing drug-use history. Additionally, a method to estimate the day of death using hair was previously developed by analyzing a single hair strand segmented at 0.4-mm intervals (micro-segmental hair analysis). However, for drowned bodies, drugs in the hair may be washed out due to soaking in water for extended periods. To evaluate the possibility of measuring drug distribution in the hair of drowned bodies, drug stability in hair samples soaked in various aqueous solutions was examined. First, reference hair strands of drug users containing specific drugs consistently along the hair shaft were prepared. The participants ingested 4 hay-fever medicines (fexofenadine, epinastine, cetirizine, and loratadine) every day for approximately 4 months before hair collection. Each reference strand was divided into regions, and each region was soaked in different solutions containing various solutes for extended periods up to approximately 2 months. In solutions without divalent ions (Ca2+ and Mg2+), the drug content in the hair decreased up to approximately 5 % with increasing salt concentration and soaking time. However, the decreased drug content was negligible in solutions containing divalent ions, implying that the divalent ions prevented drugs contained in hair from washing out. As natural river and sea waters contain divalent ions, the drugs in hair were hardly washed out even when the hair was soaked for 2 months. Thus, it was concluded that drug-distribution measurements using micro-segmental analysis can also be applied to the hairs of drowned bodies.

The impact of anatomy variation on temperature based time of death estimation.

Temperature-based time of death estimation using simulation methods such as the finite element method promise higher accuracy and broader applicability in nonstandard cooling scenarios than established phenomenological methods. Their accuracy depends crucially on the simulation model to capture the actual situation, which in turn hinges on the representation of the corpse's anatomy in form of computational meshes as well as on the thermodynamic parameters. While inaccuracies in anatomy representation due to coarse mesh resolution are known to have a minor impact on the estimated time of death, the sensitivity with respect to larger differences in the anatomy has so far not been studied. We assess this sensitivity by comparing four independently generated and vastly different anatomical models in terms of the estimated time of death in an identical cooling scenario. In order to isolate the impact of shape variation, the models are scaled to a reference size, and the possible impact of measurement location variation is excluded explicitly by finding measurement locations leading to minimum deviations. The thus obtained lower bound on the impact of anatomy on the estimated time of death shows, that anatomy variations lead to deviations of at least 5-10%.

Assessing Intrauterine Retention according to Microscopic Stillbirth Features: A Cluster Analysis Approach.

Background: Previous studies identified microscopic changes associated with intrauterine retention of stillbirths based on clinical time of death. The objective of this study was to utilize unsupervised machine learning (not reliant on subjective measures) to identify features associated with time from death to delivery. Methods: Data were derived from the Stillbirth Collaborative Research Network. Features were chosen a priori for entry into hierarchical cluster analysis, including fetal and placental changes. Results: A four-cluster solution (coefficient = 0.983) correlated with relative time periods of "no retention," "mild retention," "moderate retention," and "severe retention." Loss of nuclear basophilia within fetal organs were found at varying rates among these clusters. Conclusions: Hierarchical cluster analysis is able to classify stillbirths based on histopathological changes, roughly correlating to length of intrauterine retention. Such clusters, which rely solely on objective fetal and placental findings, can help clinicians more accurately assess the interval from death to delivery.

[Ophthalmotonus examination in children (4-17 years) to determine the time of death]. / Izuchenie urovnya oftal'motonusa u detei (4­17 let) dlya opredeleniya davnosti nastupleniya smerti.

This article presents data on the analysis of intravital and postmortem intraocular pressure (IOP) values in children aged 4 to 17 years. Intravital ophthalmotonus values were analyzed according to medical records of 991 children; the mean value for the age of 4-17 years was determined as 19±3 mm Hg with a confidence level of more than 95%. Postmortem IOP values were studied in 158 deceased subjects (28.440 measures) with follow-up from 1 to 12 h after death. The relationship between postmortem IOP values and time in children aged 4 to 17 years is linear, allowing to calculation the time of death by mathematical modeling and determining the predicted time of death range with a probability of more than 95%. Postmortem IOP values in the examination of deceased children aged 4 to 17 years can be used as an additional criterion in determining the time of death as a postmortem interval with a confidence not less than 95% with the minimum range not less than 2 hours.

[Ecological aspects of postmortem microbiome and possibility of their use in forensic practice]. / Ekologicheskie aspekty posmertnogo mikrobioma i vozmozhnost' ikh ispol'zovaniya v praktike sudebno-meditsinskoi ekspertizy.

Through experimental reproduction of the decomposition process using the cadaver of rabbit Oryctolagus sp., the dynamics of cadaver microflora was studied; the dominant bacterial taxa were isolated in pure culture and identified; their ecological and trophic profiles and biodiversity were described based on the values of Simpson and Menchinic ecological indices. The dependence of cadaver rotting and skeletonization rate on the taxonomic profile of microorganisms, decomposition period, and abiotic environmental factors (temperature, acidity, soil moisture) was demonstrated. The data obtained contribute to justifying the use of microbiological methods in forensic practice. To establish objective causality patterns of microbial transformation of organic matter in nature, further targeted study of ecological patterns of cadaveric microflora is necessary.

Estimation of the time of death by measuring the variation of lateral cerebral ventricle volume and cerebrospinal fluid radiodensity using postmortem computed tomography.

Using postmortem CT (PMCT), changes in the volume of the lateral cerebral ventricles (LCVs) and modifications of the radiodensity of cerebrospinal fluid (CSF) have been examined to identify a possible relationship between these changes and the time of death. Subsequent periodical CT scans termed "sequential scans" for ten corpses at known time of death were obtained, and a 3D segmentation of the entire LCV was carried out to measure its volume and radiodensity over time from ~ 5.5- h up to 273-h postmortem. A linear decrease of the LCV volume for all the cases was observed in the investigated time range, together with an overall logarithmic increase of radiodensity. Although a larger sampling should be performed to improve the result reliability, our finding suggests that the postmortem variation of CSF radiodensity can be a potentially useful tool in determining postmortem interval, a finding that is worthy of further investigation.

Postmortem expression of apoptosis-related genes in the liver of mice and their use for estimation of the time of death.

PURPOSE: A major challenge in forensic medicine is to estimate the postmortem interval (PMI). Several approaches had been tried to determine the time of death, including physical and chemical changes. This study aims to explore the postmortem changes in the expression of apoptosis-related genes in the liver of mice and to use these changes for estimation of the PMI. METHODS: Hepatic tissue was collected from sacrificed mice immediately after death (the control group) and at 3, 6, 9, 12, 18, and 24 hours after death. Four apoptosisrelated genes were selected as target genes, which are Caspase 3 (Casp3), B cell leukemia/ lymphoma 2 (Bcl2), BCL2-associated X protein (Bax), and Transformation related protein 53 (Trp53), and their relative expression was measured using quantitative PCR. miR-122 was used as a reference gene for normalization of the Ct (threshold cycle) values of the target genes. RESULTS: The results revealed that the postmortem expression of Casp3 increased in a time-dependent manner; the expression of Bax increased from 3 to 18 hours followed by a decrease at 24 hours after death; the expression of Bcl2 decreased in a time-dependent manner after death; the expression of Trp53 increased from 3 to 6 hours and then started to decrease from 9 to 24 hours after death. CONCLUSION: Based on the observed changes in the expression level of these genes, mathematical models were established to estimate the PMI. Further research is needed to investigate these markers and mathematical models in human tissues.

Estimation of the time since death based on body cooling: a comparative study of four temperature-based methods.

The estimation of the time since death is an important task in forensic medicine that mainly relies on body cooling in the early post-mortem period. The rectum has been traditionally used to determine the central core temperature after death, though the external auditory canal has been proposed as an alternative site by several authors. The objective of this study was to assess the ability of four body temperature-based methods (Henssge's rectal nomogram, Henssge's brain nomogram, and Baccino's both interval and global formulae based on ear temperature) to estimate the post-mortem interval (PMI). PMI calculations were carried out based on ear and rectal temperature measurements performed with a reference metal probe on 100 inpatient bodies with an average PMI of 4.5 ± 2.5 h. For practical purposes, ear temperature measurements were applied to Henssge's brain nomogram. All methods could be applied to 81 cases, since high body temperatures prevented the rectal nomogram method from being used in most of the remaining cases. The actual PMI was within the time interval (95% CI) provided by the rectal nomogram method in 72.8% of cases, and in 63.0% to 76.5% of cases when using ear temperature-based methods. The proportions of adequate estimates did not differ statistically between the different methods. When the methods failed to provide a reliable time interval, all except the brain nomogram tended to underestimate the PMI. Similar results were obtained in the subgroup of normothermic patients at the time of death (n = 63), confirming that the PMI calculations had not been biased by the inclusion of patients with thermoregulation disorders. Our findings are in accordance with the published literature which suggests that ear temperature-based methods are as reliable as those based on rectal temperature for estimating the early PMI and that they may be used as quick, simple, and non-invasive methods at the scene, although caution should be taken in interpreting their results given their high error rates. However, further research including field studies is recommended to confirm their practical relevance in forensic casework.

Postmortem MRI Characterization of Cadaveric Hypostases in Deceased Newborns.

Using postmortem MRI, we studied the features of the development of internal cadaveric hypostasis in dead newborns. Postmortem radiological and pathoanatomical examination of 62 bodies of newborns and infants who died at the age of 1.5 h to 49 days was carried out. After the death was ascertained, prior to MRI, the bodies were stored in a refrigerator at 4°C in the supine position. Depending on the duration of the postmortem period (2-72 h), all observations were divided into eight groups. Prior to autopsy, an MRI scan was performed in T1 and T2 standard modes, followed by analysis of the presence and severity of the gradient line of the intensity of the MR signal in the liver and lung tissue in the ventral (overlying) and dorsal (underlying) areas, as well as the presence of a gradient of the intensity of the blood signal in the heart cavity and in the aortic lumen. The main manifestations of cadaveric hypostasis in the liver and lungs are changes of the MR signal intensity in the ventral and dorsal regions with the appearance of a horizontal gradient of the MR signal intensity, which reflects the location of the body after death. In the heart cavity and in the aortic lumen, there is also a gradient of the blood signal intensity of various severity with the visualization of two or three of its layers. The revealed features of the MRI signal intensity and, accordingly, the presence of its horizontal gradient depended not only on the MRI mode of the study, but also on the studied organ and the duration of the postmortem period. This should be taken into account when analyzing the results of virtopsy and determining the links of thanatogenesis of dead newborns and infants.

[Postmortem intraocular pressure values in children (0-3 years old) depending on time elapsed from the moment of death]. / Posmertnye znacheniya vnutriglaznogo davleniya u detei (0­3 goda) v zavisimosti ot davnosti nastupleniya smerti.

This article presents data on the analysis of intravital and postmortem intraocular pressure values in children aged 0 to 3 years. Intravital intraocular pressure values were analyzed according to medical records in 1 643 children, and the average values were calculated. The intravital intraocular pressure values in children aged 0 to 2 years were found to be 14±2 mm Hg, and in children aged 2 to 3 years, 15±3 mm Hg, with an error-free prediction probability of more than 95 %. Postmortem intraocular pressure values were determined in 12 960 measurements in 192 deceased patients with a time elapsed from the moment of death ranging from 1 to 12 hours. It was demonstrated that postmortem intraocular pressure values in the examination of deceased children aged 0 to 3 years can be used as an additional criterion in determining the time of death as a postmortem interval with a probability of error-free prediction not less than 95 % with the minimum range not less than 3 hours.

[Numerical method for solving double exponential models of corpse cooling in the determination of the time of death]. / Chislennyi metod resheniya dvoinykh eksponentsial'nykh modelei okhlazhdeniya trupa pri ustanovlenii davnosti nastupleniya smerti.

The objective of the study is to establish a numerical method for solving double exponential models of corpse cooling and to develop on its basis applications designed to determine the time of death (ToD). The search for the radicals of double exponential models of corpse cooling using Newton's method was performed. Mathematical operations were performed using the software Wolfram|Alpha. Calculations were performed using Microsoft Excel applications of the Office 2016 package. The computer program code was compiled in the C# programming language using the Microsoft Visual Studio 2019 application. A numerical method for solving double exponential models of corpse cooling based on Newton's method is proposed. The method is implemented in a series of Warm Bodies application programs designed to determine ToD by measuring rectal or cranioencephalic temperature based on Marshall-Hoare and Henssge equations. The method provides the continuity of raw data and eliminates errors associated with the round off the measured physical values in the equations. The developed programs are recommended to be used in forensic medical practice for the determination of ToD.

[To the study of the corpse tissues' impedance dynamics in the late postmortem period]. / K izucheniyu dinamiki impedansa tkanei trupa v pozdnem posmertnom periode.

The purpose of this work is to establish the dynamics of the electrical conductivity of various corpse tissues using impedance measurements to assess this method for diagnosing the time of death. It was studied the values of the tissue impedance from the corpses of 8 persons of both sexes and different ages (30-50 years) who died from various causes, with the known date of death. A Keysight U1731 parting was used with two probes, which are stainless steel needles with a diameter of 0.5 mm and a 5 mm immersion length. The analysis of special literature on using indicators of the electrical conductivity dynamics of the corpse tissues, determined by the method of impedance measurement, in the early and late postmortem periods to diagnose the time of death. Trial measurements of a methodological nature were carried out with diagnostic zones: skin, cartilage tissue and tendon. The impedance-metric approach is promising for the purposes of forensic medical diagnostics of the time of death; however, it requires more careful experimental work to establish the dynamics of changes in the total electrical resistance of various tissues of a whole corpse over a long period from the moment of death.

[The forensic implications of the relationship between the proteolytic enzymes activity and the changes in NADH and FAD fluorescence intensity in skeletal muscle when determining the time of death (experimental study)]. / Sudebno-meditsinskoe znachenie vzaimosvyazi aktivnosti proteoliticheskikh fermentov i dinamiki intensivnosti fluorestsentsii kofermentov NADH i FAD v skeletnoi myshtse pri diagnostike davnosti nastupleniya smerti (eksperimental'noe issledovanie).

OBJECTIVE: Evaluation of the relationship between the activity of proteolytic enzymes (cathepsin D and calpains) and the dynamics of the fluorescence intensity of the coenzymes nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) in the rats' skeletal muscles in relation to the time of death. The proteolytic activity of enzymes in rat skeletal muscle was determined at the postmortem time points corresponding to the most significant changes in the dynamics of coenzymes NADH and FAD fluorescence intensity. The proteolytic enzymes activity was found to be low during the period of increasing intensity of NADH fluorescence observed within 3 hours after death. An increase in the activity of proteolytic enzymes was registered in 4.5 hours after death which corresponds to the initial point of decrease in NADH fluorescence intensity. In 24 hours post-mortem, corresponding to increased FAD fluorescence intensity a significant decrease in the activity of calpains was found. The results of the study suggest that the nature of the postmortem dynamics of the fluorescence intensity of coenzymes is largely due to the peculiarities of intracellular proteolysis. The study results suggest that the pattern of post mortem changes in coenzyme fluorescence intensity is largely attributable to the specifics of intracellular proteolysis. The relationship between coenzyme fluorescence and molecular mechanisms of cell death confirms the viability and feasibility of laser-induced spectroscopy for post-mortem changes assessment when determining the time of death.

[On the question of justifying the choice of a model-object for studying the dynamics of impedance in the postmortem period]. / K obosnovaniyu vybora model'nogo ob"ekta dlya issledovaniya dinamiki impedansa v posmertnom periode.

Objective - to compare the temporal dynamics of the tissue impedance of human and pig corpses under the same conditions to substantiate the further use of pig corpses as model objects. At the first stage, we studied the tissue impedance values obtained on 4 pig cadavers with a known date of death measured with a Keysight U1731 parting. The necessity of using a model object for studying the dynamics of impedance in the postmortem period has been substantiated. An exploratory analysis was carried out that allows to put forward a hypothesis about the existence of the impedance values (absolute indicators) and dispersion coefficients (relative indicators) dependence on the time of death, and also suggests that the combination of impedance values and the corresponding coefficients can be used to judge its duration for the objects under study.

[On the issue of a comprehensive diagnosis of death coming in the late postmortem period]. / K voprosu o kompleksnoi diagnostike davnosti nastupleniya smerti v pozdnem posmertnom periode.

According to specialized literature and the results of our own experiments to carry out a comprehensive study to find criteria for determining the time of death in the late postmortem period. It turned out that a combined assessment of microbiological, entomological and biophysical data obtained in the study of a corpse is advisable for medical diagnostics of the duration of the postmortem interval, which does not exclude the need to compare them with the results obtained by traditional morphological methods. From an applied point of view, it is very important to «standardize¼ the conditions of such studies. For an in-depth study of the nature of cause-and-effect relationships of phenomena occurring in biological tissues in the late postmortem period, it is very interesting to perform microbiological, entomological and biophysical studies under different environmental conditions, but according to a single program and on a single methodological basis.

Estimating the time of death with infrared tympanic thermometer: a new prospective study in France.

Very few studies are available on the use of infrared tympanic thermometer to estimate the postmortem interval. The purpose is to observe the decrease of the infrared tympanic temperature according to the postmortem interval under standardized conditions and to compare with the gold standard (rectal temperature). One hundred seventeen cadavers are included at the mortuary of the University Hospital of Nancy from 1 June 2015 to 1 June 2016. The infrared tympanic temperature is measured twice in each ear for each cadaver with a control of these measurements and the taking of rectal temperature for the part of them. In our experiments, the reproducibility of the measurements was excellent between both the ears of one body [intra class coefficient correlation [ICC] = 0.952], the right ear and the left ear with a same observer [ICC = 0.853] and the different observers [ICC = 0.830]. The postmortem interval is correlated with the infrared tympanic temperature (rho = - 0.483; p < 0.0001) with an average of 3.79 h ± 2.38 h. A calculation method is developed (postmortem interval = 16.14 - 0.39 × infrared tympanic temperature). Even if the correlation with the gold standard was correct (rho = 0.505), it is not associated with the postmortem interval (p = 0.0702) due to weakness of the sample. Despite early and only time point postmortem measurements, these results are promising and might impact the forensic science community by drawing the attention of researchers to the estimation of the time period since death and by developing a simple and non-invasive method, even for non-medical investigators at the scene.

Investigation of bovine abortion and stillbirth/perinatal mortality - similar diagnostic challenges, different approaches.

This pracademic paper reviews current bovine foetopathy (abortion and stillbirth) case definitions, reporting and triage, and causes and time-of-death and proposes veterinary practitioner-focused investigative standard operating procedures (SOPs). Issues of under- and over-triage and intra-institutional SOP harmonisation are also discussed. It is proposed that an 'observable abortion' (120-260 days of gestation) is a more practitioner-friendly definition of abortion for reporting and benchmarking purposes and that the term 'peristillbirth' can replace stillbirth and perinatal mortality. Diagnosis of bovine foetopathy involves an investigative triad of the farmer, veterinary practitioner and the veterinary diagnostic laboratory. However, the poor sensitivity of abortion reporting undermines the value of currently adopted scanning/passive surveillance; parallel active surveillance/sentinel herd models should also be employed. The approach to abortion investigation differs from that of peristillbirth. The former should include collecting a herd and case history, examination and sampling of dam and cohorts and sampling of the foetus and placenta. A sample selection decision tree is provided to assist test selection. In peristillbirths, non-infectious and periparturient causes-of-death are more important hence the anamnesis must focus on peristillbirth risk factors and calving management. The foetopsy, while including the sampling menu appropriate to aborted foetuses, must also include a detailed internal and external examination of the carcass for lesions indicative of periparturient causes-of-death. In addition, for aborted foetuses the time-of-death is not important as the foetus is generally not viable; however, for the peristillbirth the time-of-death is critical as it provides useful information for the farmer to address modifiable risk factors and to alter their perinatal management. Reporting of the ultimate cause-of-death is more useful to prevent future abortions and peristillbirths though the proximate cause-of-death is often reported in the absence of a complete clinical anamnesis. Finally, the common reasons for diagnosis not reached (DNR) and the limitations of current investigative approaches are discussed.

Biochemical markers of time since death in cerebrospinal fluid: A first step towards "Forensomics".

The accurate estimation of the time of death is a challenge in forensic medicine, as the methods routinely used to assess the postmortem interval (PMI) are far from being precise. Over the past decades, biochemical methods have been implemented on postmortem samples to improve the precision of PMI estimation. Studies have focussed on the biochemical profiles of closed compartment body fluids, as they are preserved longer than blood after death and are thus subject to confined postmortem chemical changes. Cerebrospinal fluid (CSF) has been considered a suitable fluid to investigate these changes, as it is found in large amounts and is easy to sample. Moreover, the main molecules found in CSF have known reference values in living subjects, unlike most other body fluids. In this literature review, we focus on the panel of biomarkers that have been studied in CSF based on their potential of offering information on the time of death. The interest in these biomarkers for casework and the research perspectives in this field are discussed. Integrating data from different methods, including biochemistry, for better estimation of the time of death would represent a step forward in the forensic field, paving the way for an innovative approach that we suggest to call "Forensomics."

Post-mortem interval estimative through determination of catalase and Δ-aminolevulinate dehydratase activities in hepatic, renal, skeletal muscle and cerebral tissues of Swiss mice.

Purpose: Determining the post-mortem interval (PMI) is one of the challenging tasks in forensic science due to the lack of quick and inexpensive methods. Our objective is to develop innovative and alternative means for PMI evaluation. Methods: The relationship between PMI and enzymatic modifications in mice tissues was described. After being sacrificed, Swiss mice were randomly divided into groups according to the time elapsed since death. The activities of catalase (CAT) and δ-aminolevulinate dehydratase (δ-ALA-D) were determined in hepatic, renal, skeletal muscle and cerebral tissues. Results: CAT activity increased in kidney and brain 6 h after death and this increase remained for up to 24 h in the brain and 48 h in the kidney. δ-ALA-D had its activity decreased in the liver and kidneys in 6 h. In the skeletal muscle, δ-ALA-D activity was reduced only 48 h after death. Conversely, an increase on δ-ALA-D activity was observed in the brain at 6 h, followed by its decrease at 24 and 48 h. Conclusion: With the association of this set of results, it is possible to provide an estimate of PMI. Additionally, these results can be used as an auxiliary parameter associated with other methods to estimate PMI.