APPROACHES TO DETERMINING POST-MORTEM INTERVAL

The main approaches and problems that arise when evaluating postmortem interval are defined, ways to avoid such problems are suggested. According to the results of scientific papers analysis on that topic, it was established that in the context of post-mortem changes studies such changes developed differently during a specific period of time passed from the time of death, they also appeared in a variety of forms as a result of environmental factors influence. The factors having a significant impact on postmortem changes were specified. A review of modern methods for determining post-mortem interval was conducted and methods for further improvement of the assessment of postmortem interval were proposed. The use of methods for assessing the PMI by means of the cadaveric phenomena does not always provide for investigating authorities necessary information due to the relatively large time interval in methods based on such changes. Researchers also note the presence of certain shortcomings in the use of existing methods. Current research using laser polarimetry methods have made it possible to establish post-mortem interval with relatively high accuracy. However, high prices and limited availability of equipment used in laser polarimetry methods preclude from using them in everyday practice of forensic medical examiners. When conducting studies on histological and biochemical changes in tissues of internal organs, certain morphological (decrease in optical density) and biochemical (changes in the levels of biochemical markers) changes in the early post-mortal period were identified, which will enable the development of specific tables where such changes would be linked to a specific post-mortem time period during certain short periods of time. Although changes in the conducted research were recognized only in the early post-mortem period and only in muscle tissue, further research on other tissues that are more resistant to post-mortem changes are likely to provide results that would be less affected by ambient temperature, exposure of a corpse to the sun rays, amount of clothing on a corpse, etc.) and also would be more accurate than most existing methods.

Download Full-text

Spectral Transmission of Porcine Crystalline Lens at Post-Mortem Interval

Journal of the Nigerian Optometric Association ◽

10.4314/jnoa.v22i1.6 ◽

2020 ◽

Vol 22 (1) ◽

pp. 35-43

Author(s):

Oluwasola M. Ojo ◽

Olajire B. Ajayi ◽

Mutali J. Musa

Keyword(s):

Crystalline Lens ◽

Forensic Evaluation ◽

Time Interval ◽

Post Mortem ◽

Spectral Transmission ◽

Strong Negative Correlation ◽

Post Mortem Interval ◽

Benin City ◽

Significant Difference ◽

Porcine Eyes

Purpose: Determining the total spectral transmission of the porcine crystalline lens at various post mortem intervals. Method: An experimental study conducted in the Department of chemical Pharmacology, Faculty of pharmacy, University of Benin. Twenty pairs of porcine eyes were obtained from an abattoir in Benin City. The crystalline lenses were carefully extracted from the enucleated porcine eyes at various post- mortem intervals (0, 12, 24, 36 and 48hours) and their spectral transmissions were measured using a T80 UV-VIS Spectrophotometer. Measurement at 0 hour was used as a control being the baseline. Result: The result showed a strong negative correlation between increased post mortem intervals and transmission of the crystalline lens for both eyes, as the post-mortem time interval increases, the transmission of long wavelengths (r = -0.992, P = 0.001), mid wavelengths (r = -0.994, P = 0.000) and short wavelengths(r = -0.991, P = 0.001) decreases significantly. It was also observed there was no significant difference (P> 0.05) existed between both eyes in the different wavelength regions with increased post mortem interval. Conclusion: The study shows that time after death has effect on the spectral transmission of crystalline lens which can serve as important information in forensic evaluation. Key words: Post mortem interval, crystalline lens, spectral transmission, spectrophotometer and porcine.

Download Full-text

CONSISTENT PATTERNS OF POSTMORTAL STRUCTURAL AND BIOCHEMICAL CHANGES IN DIAPHRAGM MUSCULAR TISSUE: IMPORTANCE FOR FORENSIC MEDICAL ESTIMATION OF TIME OF DEATH COMING

Актуальні проблеми сучасної медицини Вісник Української медичної стоматологічної академії ◽

10.31718/2077-1096.19.1.71 ◽

2019 ◽

Vol 19 (1) ◽

pp. 71-76

Author(s):

N.S. Konoval

Keyword(s):

Acid Phosphatase ◽

Muscle Tissue ◽

Biochemical Changes ◽

Diaphragm Muscle ◽

Time Interval ◽

Muscular Tissue ◽

Time Of Death ◽

Post Mortem ◽

Time Intervals ◽

Tissue Samples

The issue on estimating the time of death coming still remains a challenge that requires a lot of questions to be answered, therefore, the development of new scientific methods aimed at overcoming these difficulties is a top priority in solving the problem of estimating the time of death coming. The purpose of this study was to investigate the structural and biochemical changes in the muscle tissue of the diaphragm in the early post-mortem period. The muscular tissue samples of the diaphragm just below the lungs taken from 30 human corpses in the early post-mortem period (in time intervals of 3-13 hours from the onset of death) were investigated. We studied structural and biochemical markers in the homogenates of the muscles of the diaphragm: the content of glycogen, acid phosphatase, lactate, lactate dehydrogenase, lipofuscin, and cholinesterase. It was found out that in the early post-mortem period structural and biochemical changes in the muscle tissue of the diaphragm are characterized by regular morphological biochemical and biophysical changes. In particular, the post-mortem dynamic changes in glycogen, acid phosphatase and lipofuscin levels is most significant; i.e. within the time interval of 3–9 hours from the time of death coming, the assessment of the “cholinesterase / glycogen or acidic phosphatase / glycogen” ratio is the most diagnostically valuable, then after 9 hours the only “cholinesterase / glycogen” ratio is meaningful. The content of glycogen in the homogenates of the diaphragm muscle tissue depending on the time of death coming ranged from (4.765 ± 0.058) mg / g in 3 hours, to (1.883 ± 0.027) mg / g in 13 hours after the death coming, reliably ( p <0.001) differing in time intervals. The inverse pattern was characterized by the acid phosphatase content: (2.748 ± 0.019) u / g in 3 hours and (4.49 ± 0.032) u / g in 13 hours. These markers are the most significant to demonstrate the patterns and can be used as critically important signs in forensic diagnosis.

Download Full-text

RELATION OF POSTMORTEM CHANGES DEVELOPMENT AND EXACT POSTMORTEM INTERVAL

Inter Collegas ◽

10.35339/ic.7.2.72-75 ◽

2020 ◽

Vol 7 (2) ◽

pp. 72-75

Author(s):

E. Grygorian ◽

V. Olkhovsky ◽

M. Gubin

Keyword(s):

Rank Correlation ◽

Postmortem Interval ◽

Medical Examiner ◽

Postmortem Changes ◽

Time Interval ◽

Time Of Death ◽

Cross Sectional ◽

Positive Correlation ◽

Total Body Score ◽

Total Body

RELATION OF POSTMORTEM CHANGES DEVELOPMENT AND EXACT POSTMORTEM INTERVAL Grygorian E., Olkhovsky V., Gubin M. Purpose: Precise postmortem interval’s evaluation is crucial in cases when violent types of death are suspected by forensic medical examiner. There are different factors that could affect results of postmortem interval (PMI) evaluation by forensic medical expert. The aim of this study was to study connections between the known postmortem time interval and the degree of particular postmortem changes’ development. Materials and Methods: A cross-sectional analysis of 116 forensic medical examinations of deceased persons (of female persons n = 58, of males n = 58), in cases of non-violent death, was performed. Data about time of death was obtained from police preliminary records provided to the examination - only cases with known time of death prescription were included to study. Postmortem changes were evaluated by Total Body Score (TBS) [1] at equal time interval after death (48 hours ± 3 hours). Interconnection between postmortem changes degree and PMI was estimated using Spearman’s rank correlation. Difference between sexes was evaluated using Mann-Whitney U test. Results: “Thickness of clothes” criterion reached the highest positive correlation coefficient, “ambient temperature” criterion had also a significant positive correlation. The rest of studied criteria had very weak correlation with the development of postmortem changes. Conclusions: Several criteria had significant (p < 0.05), yet week, impact on the postmortem changes’ development. The other criteria were statistically insignificant. Keywords: forensic medicine, forensic medical examination, postmortem interval, thanatology. Резюме. ЗВ’ЯЗОК РОЗВИТКУ ПОСТМОРТАЛЬНИХ ЗМІН І ДАВНОСТІ НАСТАННЯ СМЕРТІ Григорян Е.К., Ольховський В.О., Губін М.В. Мета: Точна оцінка терміну, що пройшов з моменту настання смерті, має вирішальне значення у випадках, коли судово-медичний експерт підозрює насильницькі види смерті. Існують різні фактори, які можуть вплинути на результати оцінки давності настання смерті (ДНС) судово-медичним експертом. Метою даного дослідження було вивчення зв’язку між відомою давністю настання смерті і ступенем розвитку конкретних посмертних змін. Матеріали та методи: Було проведено аналіз 116 судово-медичних експертиз померлих осіб (жінок n = 58, чоловіків n = 58) у випадках ненасильницької смерті. У дослідження були включені тільки випадки з відомим терміном давності настання смерті, дані про час настання смерті були отримані із супровідної документації правоохоронних органів, наданої на експертизу. Посмертні зміни оцінювали за методом Total Body Score (TBS) [1] через однаковий проміжок часу після настання смерті (48 годин ± 3 години). Взаємозв’язок між ступенем посмертних змін і ДНС був оцінений з використанням рангової кореляції Спірмена. Різниця між статями була оцінена з використанням U-критерію Манна-Уїтні. Результати: Критерій «товщина одягу» мав найвищий позитивний коефіцієнт кореляції, критерій «температура навколишнього середовища» також мав значну позитивну кореляцію. Решта вивчених критеріїв мали дуже слабку кореляцію з розвитком посмертних змін. Висновки: Кілька критеріїв мали значний (р <0,05), але слабкий вплив на розвиток посмертних змін. Решта критеріїв були статистично незначущими. Ключові слова: судова медицина, судово-медична експертиза, давність настання смерті, танатологія. Резюме. СВЯЗЬ РАЗВИТИЯ ПОСТМОРТАЛЬНЫХ ИЗМЕНЕНИЙ И ДАВНОСТИ НАСТУПЛЕНИЯ СМЕРТИ Григорян Э.К., Ольховский В.А., Губин Н.В. Цель: Точная оценка срока, прошедшего с момента наступления смерти, имеет решающее значение в случаях, когда судебно-медицинский эксперт подозревает насильственные виды смерти. Существуют различные факторы, которые могут повлиять на результаты оценки давности наступления смерти (ДНС) судебно-медицинским экспертом. Целью данного исследования было изучение связей между известной давностью наступления смерти и степенью развития конкретных посмертных изменений. Материалы и методы: Был проведен анализ 116 судебно-медицинских экспертиз умерших лиц (женщин n = 58, мужчин n = 58) в случаях ненасильственной смерти. В исследование были включены только случаи с известным сроком давности наступления смерти, данные о времени наступления смерти были получены из сопроводительной документации правоохранительных органов, предоставленной на экспертизу. Посмертные изменения оценивали по методу Total Body Score (TBS) [1] через одинаковый промежуток времени после наступления смерти (48 часов ± 3 часа). Взаимосвязь между степенью посмертных изменений и ДНС была оценена с использованием ранговой корреляции Спирмена. Различие между полами было оценено с использованием U-критерия Манна-Уитни. Результаты: Критерий «толщина одежды» имел наивысший положительный коэффициент корреляции, критерий «температура окружающей среды» также имел значимую положительную корреляцию. Остальные изученные критерии имели очень слабую корреляцию с развитием посмертных изменений. Выводы: Несколько критериев оказали значительное (р <0,05), но слабое влияние на развитие посмертных изменений. Остальные критерии были статистически незначимыми. Ключевые слова: судебная медицина, судебно-медицинская экспертиза, давность наступления смерти, танатология.

Download Full-text

Post-mortem interval estimation by laser-induced fluorescence of polycrystalline cerebro-spinal fluid films images

Forensic-medical examination ◽

10.24061/2707-8728.2.2016.7 ◽

2016 ◽

pp. 32-38

Author(s):

Marta Garazdiuk

Keyword(s):

Short Range ◽

Interval Estimation ◽

Statistical Processing ◽

Laser Induced Fluorescence ◽

Diagnostic Methods ◽

Postmortem Changes ◽

Two Dimensional ◽

Post Mortem ◽

Fluid Films ◽

Post Mortem Interval

There are many new optical diagnostic methods (photometric, polarization and correlation techniques) of biological tissue structure assessment, which are the most perspective in post-mortem interval determination. The purpose of the work. Development and testing of the two-dimensional Stokes-polarimetric mapping of biological layers own fluorescence to evaluate accuracy of the post-mortem interval (PMI) assessment using statistical analysis of postmortem changes dynamics of the coordinate distributions values of polycrystalline films of liquor (PFL) images laser-induced fluorescence polarization intensity (LIFPI). Materials and methods. Objects of investigation are PFL, taken in 72 corpses with accurately known time of death and 20 healthy volunteers. The cause of the death was cardiovascular accident. Coordinate distributions of LIFPI image values were determined for each sample of PFL in the optical arrangement of the Stokes polarimeter in short-range spectrum of optical radiation. The value of statistical points 1 - 4 th order was perfomed for each two-dimensional distribution of PFL images LIFPI values. Statistical processing of the calculated values of set of points that characterize the LIFPI distributions was carry out. The depending on the time change of the most sensitive points of statistical values were built. Results and conclusions. Two-dimensional Stokes-polarimetric mapping distributions LIFPI of PFL images may be used in determination of the PMI. Statistical points of the first and fourth order are the most sensitive PFL optical values to evaluate postmortem changes by short-range fluorescence.

Download Full-text

COMPARATIVE ANALYSIS OF LASER POLARIMETRY METHODS OF POLYCRYSTALLINE FILMS OF CEREBROSPINAL FLUID FOR POST-MORTEM INTERVAL ESTIMATION

CBU International Conference Proceedings ◽

10.12955/cbup.v7.1445 ◽

2019 ◽

Vol 7 ◽

Author(s):

Marta Garazdiuk ◽

Viktor Bachynskіy ◽

Oleh Vanchuliak ◽

Oleksandr Garazdiuk ◽

Yuliya Sarkisova

Keyword(s):

Cerebrospinal Fluid ◽

Interval Estimation ◽

Accurate Estimation ◽

Time Interval ◽

Two Dimensional ◽

Post Mortem ◽

Polycrystalline Films ◽

Technological Support ◽

Post Mortem Interval ◽

Stokes Polarimetry

Obtaining the most accurate information about an object during its evaluation is one of the most urgent tasks of current forensic medical examination. That is why the application of new technologies in forensic medical expertise becomes an integral part of the technological support of forensic examination institutions. Purpose: To compare the effectiveness of cerebrospinal fluid polycrystalline films, microscopic images, two-dimensional Stokes-polarimetry, and autofluorescent polarimetry in post-mortem interval estimation over long- and short-term time intervals. Material and methods. The object of the study is cerebrospinal fluid donated from 70 corpses (experimental group) and 20 living persons (control group). Methods used: two-dimensional Stokes-polarimetry, autofluorescent polarimetry. Results: Quantitative characteristics of the cerebrospinal fluid’s polycrystalline films statistical moments allows us to establish relations between them and the duration of the post-mortem interval at a significant time interval. However, this method does not consider the morphology of the film of the cerebrospinal fluid and its coordinate structure. In contrast to this method, fluorescence microscopy considers the biochemical composition of the biological fluid and carries information about the concentration of molecular complexes of proteins, NADH, flavins, porphyrins, etc. In the early post-mortem period, changes in the cerebrospinal fluid begin precisely with changes in the concentration of biochemical compounds, and crystalline changes are secondary, so it can be argued that this method is most effective for diagnosing the progression of the time in the first hours after death. Conclusions: Fluorescent laser polarimetric methods allow accurate estimation of the postmortem interval during the first hours after death. While, the polarization methods is more effective during the long-term periods of time, but has less precision.

Download Full-text

FORENSIC MEDICAL ASSESSMENT OF MORPHOLOGICAL CHANGES AT DIFFERENT POSTMORTEM INTERVAL

Inter Collegas ◽

10.35339/ic.8.3.177-181 ◽

2021 ◽

Vol 8 (3) ◽

pp. 177-181

Author(s):

E. Grygorian ◽

V. Olkhovsky ◽

M. Gubin ◽

V. Shishkin

Keyword(s):

Morphological Changes ◽

Rank Correlation ◽

Postmortem Interval ◽

Medical Examiner ◽

Postmortem Changes ◽

Time Interval ◽

Time Of Death ◽

Internal Organs ◽

Average Percentage ◽

Spearman’S Rank Correlation

Purpose: The postmortem interval (PMI) evaluation is one of priorities while performing a forensic medical examination of corpse. To date, there is lack of information of morphological postmortem changes of some internal organs. Considering the persistent need to develop the method for a precise assessment of PMI, postmortem changes in these potentially informative organs were evaluated. The aim of study was to analyze morphological postmortem changes in prostate and uterus. Materials and Methods: histological samples of 40 prostate tissues and 40 uterus (n=80) from corpses of deceased aged 18-75 years. Only cases with known time of death were included to study, the time of death was taken from police reports. Exclusion criteria were cases of violent death, cases of death with massive blood loss, tumors of studied internal organs, cases when diagnosis was not made by a forensic medical examiner. The PMI of studied cases ranged from 1 to 6 days. Histological slides were made with a staining by hematoxylin and eosin, x200 magnification, using Olympus ВХ41 and Olympus ВХ46 microscopes, Olympus SC50 camera. Postmortem morphological changes were evaluated by a calculation of blank spaces percentage in microscopical structures using a JS-based program. Connection between PMI and morphological changes was calculated by the Spearman’s rank correlation. Results: the average percentage of blank spaces in uterus tissues was smaller than in prostate tissues (1,99 and 9,65 relatively). The slower growing of blank spaces was in uterus. In prostate samples, a notable increase of blank spaces was observed between 48 and 72 hours after the death. After this period, the increase slowed down and then an increase was observed again between 120 and 144 hours after the death. In uterus samples, a slight acceleration observed between 72 and 120 hours after the death and then slowing down between 120 and 144 hours after the death. Blank spaces in evaluated histological slides were increasing directly proportional to the PMI, a statistically significant interconnection was defined (p < 0.05). Conclusions: The morphological postmortem changes in prostate and uterus were developing at certain time frames. Blank spaces percentage, in studied histological slides, were increasing directly proportional to the PMI increase, a statistically significant interconnection was defined. Therefore, the results of study show the possibility of the evaluation of a postmortem time interval by assessing such morphological changes in these organs, which could be used in forensic medical cases.

Download Full-text

Evaluating the utility of time-lapse imaging in the estimation of post-mortem interval: An Australian case study

Forensic Science International Synergy ◽

10.1016/j.fsisyn.2019.08.003 ◽

2019 ◽

Vol 1 ◽

pp. 204-210 ◽

Cited By ~ 1

Author(s):

Alyson Wilson ◽

Stanley Serafin ◽

Dilan Seckiner ◽

Rachel Berry ◽

Xanthé Mallett

Keyword(s):

Time Lapse ◽

Post Mortem ◽

Post Mortem Interval ◽

Australian Case ◽

Time Lapse Imaging

Download Full-text

Impact of Comingled Heterospecific Assemblages on Developmentally Based Estimates of the Post-Mortem Interval—A Study with Lucilia sericata (Meigen), Phormia regina (Meigen) and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae)

Insects ◽

10.3390/insects12040280 ◽

2021 ◽

Vol 12 (4) ◽

pp. 280

Author(s):

Krystal R. Hans ◽

Sherah L. Vanlaerhoven

Keyword(s):

Growth Rate ◽

Development Time ◽

Lucilia Sericata ◽

Phormia Regina ◽

Calliphora Vicina ◽

Immature Stages ◽

Post Mortem ◽

Blow Fly ◽

Blow Flies ◽

Post Mortem Interval

Estimates of the minimum post-mortem interval (mPMI) using the development rate of blow flies (Diptera: Calliphoridae) are common in modern forensic entomology casework. These estimates are based on single species developing in the absence of heterospecific interactions. Yet, in real-world situations, it is not uncommon to have 2 or more blow fly species developing on a body. Species interactions have the potential to change the acceptance of resources as suitable for oviposition, the timing of oviposition, growth rate, size and development time of immature stages, as well as impacting the survival of immature stages to reach adult. This study measured larval development and growth rate of the blow flies Lucilia sericata (Meigen, 1826), Phormia regina (Meigen, 1826) and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) over five constant temperatures (15, 20, 25, 30, 35 °C), in the presence of conspecifics or two-species heterospecific assemblages. Temperature and species treatment interacted such that L. sericata larvae gained mass more rapidly when in the presence of P. regina at 20 and 30 °C, however only developed faster at first instar. At later stages, the presence of P. regina slowed development of L. sericata immatures. Development time of C. vicina immatures was not affected by the presence of P. regina, however larvae gained mass more slowly. Development time of P. regina immatures was faster in the presence of either L. sericata or C. vicina until third instar, at which point, the presence of L. sericata was neutral whereas C. vicina negatively impacted development time. Phormia regina larvae gained mass more rapidly in the presence of L. sericata at 20 °C but were negatively impacted at 25 °C by the presence of either L. sericata or C. vicina. The results of this study indicate that metrics such as development time or larval mass used for estimating mPMI with blow flies are impacted by the presence of comingled heterospecific blow fly assemblages. As the effects of heterospecific assemblages are not uniformly positive or negative between stages, temperatures or species combinations, more research into these effects is vital. Until then, caution should be used when estimating mPMI in cases with multiple blow fly species interacting on a body.

Download Full-text