Normal age-related signal change in the laryngeal cartilages

MRI may be used for detecting cartilage invasion in patients with laryngeal carcinoma. However, the normal laryngeal ossification pattern has not been studied. Our purpose was to examine the normal age-related signal patterns in the cricoid, thyroid and arytenoid cartilages on T1-weighted images. Signal in the cartilages was assessed by two radiologists in a blinded fashion using three-point scales for intensity and symmetry. Statistical analysis consisted of logistic and monotonic regression. There was excellent interobserver agreement (>85%) for all categories. The cartilages predominantly ossify symmetrically and the extent of high signal from all three increases with age. The latter may help in detection of cartilage invasion by tumor in older patients. Normal symmetry may be helpful when comparing sides for tumor invasion.     

The use of computed tomography in determining developmental changes, anomalies, and trauma of the thyroid cartilage

Recognition of injury to the hyoid bone and thyroid and cricoid cartilages is intrinsic to post-mortem examination. Due to its increasing brittleness with age the thyroid cartilage is particularly susceptible to injury following neck trauma, although there is inconsistency in the patterns of injury reported. In this study computed tomography scans of the head and neck of 431 deceased persons (235 males and 196 females) between the ages of 1 day and 100 years (mean age 35.93 ± 24.15), and including 25 victims of hangings, were examined to reveal the pattern of age-related change and the types of injury that occurred. Thyroid cartilage anomalies likely to cause confusion and be misinterpreted as trauma-related are documented. Angulation of the thyroid cartilage horns was found to change with age, and it is suggested this may be a significant factor in traumatic neck injury. Unlike in previous reports, the average age of hanging victims with fractures to the thyroid cartilage was 34 years. The base of the superior horn was the most common fracture site and in 50 % of hanging cases was associated with a ligature positioned on the thyrohyoid membrane or thyroid lamina. Although an age-related relationship exists it was not possible to establish narrow age-prediction ranges from calcification of the thyroid cartilage.     

Age estimation from ossification of sternum and true ribs using 3D post-mortem CT images in a Japanese population

Age estimation of cadavers from post-mortem “chest plate” using conventional radiography, which involves radiographic assessment of ossification around the sternum and rib ends, has been evaluated without fruitful results. This study examined the value of images of the chest plate obtained by three-dimensional post-mortem CT for estimation of age at time of death in a Japanese population. Five chest plate ossification scores were evaluated in 320 subjects, including ossification of the first costal cartilage (OF), ossification of the second to seventh costal cartilages at the rib (OR) and sternal (OS) ends, fusion of the manubriosternal joint (FM), and fusion of the xiphisternal joint (FX). OS was found to have the highest correlation with age while FM had no significant correlation. The best composite score for age estimation was the summative score for both sides of the OS and the right side of the OF and FX, for which the coefficient of determination (R²) and the standard error of estimation (SEE) were 0.608 and 12.44 years, respectively, for men and 0.590 and 14.65 years for women. The accuracy of the model was tested in a further 26 male and 24 female subjects, and the accuracy rate within the first SEE was 57.69% and 70.83%, respectively. This rapid and non-invasive method of age estimation in the chest plate area is superior to conventional methods and could be useful for estimation of age at time of death in the Japanese population.     

钝性喉气管损伤的MSCT诊断

目的：探讨多层螺旋CT在钝性喉气管损伤（B-LTT）中的临床应用价值。方法：对喉颈部外伤后156例患者使用GE LightSpeed 16层及32层螺旋CT设备行CT检查,其中平扫111例和对比剂增强扫描45例,并通过最大密度投影（MIP）、多平面重组（MPR）、仿真内镜（VE）及容积再现（VR）等影像后处理技术进行喉软骨、喉部软组织三维成像。结果：共发现43例患者喉部损伤,包括软组织损伤28例,喉软骨骨折14例及舌骨骨折1例。喉软骨骨折14例中,甲状软骨骨折12例（右侧甲状软骨5例,左侧甲状软骨骨折3例,甲状软骨前部正中骨折4例）。同时合并环状软骨骨折3例,杓状软骨骨折2例,环杓关节脱位3例,环甲关节脱位2例,甲状腺损伤2例,皮下气肿12例,咽喉部血肿3例,颈2椎体骨折1例。MSCT显示喉软骨骨折的直接征象为喉软骨边缘不连续,可见低密度骨折线影,也可伴移位。软组织损伤表现为声门及气道狭窄,伴咽喉部血肿、皮下气肿。喉周围软组织内出现气泡是喉黏膜撕裂的间接征象。结论：螺旋CT可多方位显示喉软骨骨折部位、程度以及气道狭窄和喉黏膜撕裂情况,是诊断喉损伤快速有效的方法。     

Supraglottic carcinoma treated with curative radiation therapy: identification of prognostic groups with MR imaging

PURPOSE: To retrospectively assess the prognostic meaning of tumor characteristics depicted on pretreatment magnetic resonance (MR) images for local outcome in supraglottic squamous cell carcinoma treated with definitive radiation therapy. MATERIALS AND METHODS: Pretreatment MR images acquired in 84 patients with supraglottic carcinoma treated with curative radiation therapy were reviewed for tumor involvement of laryngeal sites including glottis, subglottis, pre-epiglottic space, laryngeal cartilages, and hypopharynx, and for extralaryngeal extension. The volume of each tumor was estimated, and mean tumor volume was calculated for the group of tumors in each T staging category. RESULTS: Results of univariate analysis showed MR imaging-determined primary tumor volume (P =.03), involvement of pre-epiglottic space (P =.008), abnormal signal intensity in thyroid cartilage (P =.04), and extralaryngeal extension beyond thyroid and/or cricoid cartilage (P =.02) to be significant predictors of local control rate. Results of multivariate analysis with the Cox regression model confirmed statistical significance for invasion of pre-epiglottic space (P =.004) and for abnormal signal intensities in thyroid cartilage adjacent to the anterior commissure (P =.04) and in cricoid cartilage (P =.01). Five-year local control rates were calculated from the regression coefficients of three independent MR imaging prognostic factors, and three prognostic groups were identified on the basis of these control rates. The 5-year local control rate in the high-risk group was 35%, significantly lower than the rates in the intermediate- and low-risk groups (60% and 89%, respectively; P =.002). CONCLUSION: MR imaging-determined pre-epiglottic space involvement and abnormal signal intensities in the thyroid cartilage adjacent to the anterior commissure and/or the cricoid cartilage are strong predictors of local outcome in supraglottic carcinoma treated with definitive radiation therapy.     

Validity and reliability of dental age estimation of teeth root translucency based on digital luminance determination

In forensic anthropological casework, estimating age-at-death is key to profiling unknown skeletal remains. The aim of this study was to examine the reliability of a new, simple, fast, and inexpensive digital odontological method for age-at-death estimation. The method is based on the original Lamendin method, which is a widely used technique in the repertoire of odontological aging methods in forensic anthropology. We examined 129 single root teeth employing a digital camera and imaging software for the measurement of the luminance of the teeth’s translucent root zone. Variability in luminance detection was evaluated using statistical technical error of measurement analysis. The method revealed stable values largely unrelated to observer experience, whereas requisite formulas proved to be camera-specific and should therefore be generated for an individual recording setting based on samples of known chronological age. Multiple regression analysis showed a highly significant influence of the coefficients of the variables “arithmetic mean” and “standard deviation” of luminance for the regression formula. For the use of this primer multivariate equation for age-at-death estimation in casework, a standard error of the estimate of 6.51 years was calculated. Step-by-step reduction of the number of embedded variables to linear regression analysis employing the best contributor “arithmetic mean” of luminance yielded a regression equation with a standard error of 6.72 years (p?<?0.001). The results of this study not only support the premise of root translucency as an age-related phenomenon, but also demonstrate that translucency reflects a number of other influencing factors in addition to age. This new digital measuring technique of the zone of dental root luminance can broaden the array of methods available for estimating chronological age, and furthermore facilitate measurement and age classification due to its low dependence on observer experience.     

Age estimation from structural changes of teeth and buccal alveolar bone level

Forensic odontology plays a vital role in the identification and age estimation of unknown deceased individuals. The purpose of this study is to estimate the chronological age from Cone-Beam Computed Tomography (CBCT) images by measuring the buccal alveolar bone level (ABL) to the cemento-enamel junction and to investigate the possibility of employing the age-related structural changes of teeth as studied by Gustafson. In addition, this study will determine the forensic reliability of employing CBCT images as a technique for dental age estimation. A total of 284 CBCT images of Malays and Chinese patients (150 females and 134 males), aged from 20 years and above were selected, measured and stages of age-related changes were recorded using the i-CAT Vision software. Lower first premolars of both left and right side of the jaw were chosen and the characteristics described by Gustafson, namely attrition, secondary dentine formation and periodontal recession were evaluated. Linear regression analysis was performed for the buccal bone level and the R values obtained were 0.85 and 0.82 for left and right side respectively. Gustafson's characteristics were analysed using multiple regression analysis with chronological age as the dependent variable. The results of the analysis showed R values ranged from 0.44 to 0.62. Therefore it can be safely concluded that the buccal bone level highly correlated with the chronological age and is consequently the most suitable age-related characteristic for forensic age estimation.     

Three-dimensional reconstructions with volume-rendering method of the arytenoid and cricoid cartilages by means of multidetector row CT]

We created volume-rendering (VR) three-dimensional (3-D) images of the larynx using a multidetector row CT. The study included 17 examinations of 15 patients. After obtaining volume data of the larynx, VR 3-D images of airways and arytenoid and cricoid cartilages were reconstructed. The threshold of airways and calcification were set as -1025/-625 HU and 80/1560 HU, respectively. The base of the vocal processes of arytenoid cartilages and cricoarytenoid joints were demonstrated at rates of 70.6% and 53.4%, respectively. VR 3-D laryngeal images were more useful in assessing anatomy than the surface-rendering images previously reported.     

Ossification and calcification of the laryngeal skeleton

Low voltage radiography of the neck was performed in 64 patients (48 males, 16 females) aged over 34 years. The degree and frequency of ossification of the thyroid and cricoid cartilage were lower in the females than in the males, especially in the anterior parts of the cartilages. The arytenoids were ossified or calcified in all females and in 94 per cent of the males. Dense homogeneous appearance of the arytenoids was present in 74 per cent of the females and 19 per cent of the males, probably due to a marked calcification of the cartilages.     

Age assessment at the time of death based on panoramic radiography

BACKGROUND: The determination of age at the time of death is an important method in forensic anthropology and paleodemography. The possible postmortem investigation of the teeth and jaws enables the determination of age at the time of death, as the bones and teeth are both resistant to degradation in soil and characterized by age-related morphological changes. The aim of this study was to determine whether the age-related changes visible on panoramic radiography correlated with age, and enabled the assessment of individual age. METHODS: Seven radiographic parameters were used in the study: tooth loss, occlusal tooth wear, pulp stones, carious teeth, periapical disease, tooth restoration, and alveolar bone loss associated with periodontal disease. RESULTS: The material comprised 314 dental panoramic tomograms of living patients of both sexes with documented age (18 to 77 years). Multiple regression equations were constructed for the age estimation, including four parameters (the number of missing teeth, the number of intact teeth, the distance of cement-enamel junction from the alveolar ridge, the number of abraded teeth). The nature of data treated by regression analysis required the careful choice of parameters, appropriate functional model for each parameter, and the experience of the investigator. With the four parameters included in equations, the error was +/- 2.55 years. CONCLUSION: This preliminary analysis showed that the conventional regression technique could be appropriate for the age estimation based on panoramic radiography, and that an additional study with a larger sample and on wider population was required.     

Computed tomographic evaluation of the acetabulum for age estimation in an Indian population using principal component analysis and regression models

The acetabulum presents as a well-preserved evidence, resistant to taphonomic degradation changes and can thus aid in the age estimation process. A CT-based examination of the acetabulum can further help simplify the process of age estimation by overcoming the time-consuming process of maceration and by doing away with the interference resulting from tissue remnants. The aim of the present study was to evaluate the role of the acetabulum for age estimation in an Indian population through a CT-based examination, using principal component analysis and regression models. CT images of 400 individuals aged 10 years and above were evaluated according to the features defined in the San-Millán-Rissech method of age estimation. Five of the seven morphological features defined by San-Millán-Rissech were appreciable on CT scans, and, to enable further statistical analysis, a cumulative score was computed using these five features. A significant correlation of 0.835 and 0.830 for the right and left acetabulum, respectively, was obtained between computed cumulative scores and chronological age of individuals. No significant sex differences were observed in the scoring of different age-related morphological changes. Regression models were generated using individual features and cumulative scores. Regression models derived using the cumulative score yielded inaccuracy values of 9.67 years for the right acetabulum and 9.15 years for the left acetabulum. Inaccuracy and bias values were computed for each individual feature, as well as for each decade, using mean point ages established within the original study. Amongst the various features, acetabular rim porosity was seen to have the lowest values of inaccuracy (11.50 years) and bias (2.32 years) and activity on outer edge of acetabular fossa the highest (inaccuracy and bias values of 22.36 years and 21.50 years, respectively). Taking into consideration this differential contribution towards age estimation, weighted coefficients and mean point ages for different morphological features were determined using principal component analysis. Subsequently, summary age models were generated from the obtained weighted coefficients and mean age values. Summary age models derived in the present study yield lower estimates of inaccuracy of 7.60 years for the right acetabulum and 7.82 years for the left acetabulum. While regression models derived in the present study allow for age estimation using even a single appreciable feature, summary age models take into account the contribution of each feature and generate more accurate estimates of age. Both statistical computations yield reduced error rates and thus can render greater applicability to the acetabulum in forensic age estimation.

     

Drowning versus postmortem submersion: Biochemical and histopathological examination and estimation of postmortem intervals (an experimental study)

Estimation of the postmortem interval (PMI) is a very essential task for forensic experts especially in criminal cases. drowning is still the most difficult tasks for forensic pathologists to be diagnosed and differentiated from a body disposed of in water following death especially after long post-mortem period. The objective of this study was to estimate the PMI in drowning in comparison to postmortem submersion using mRNA expression of AQP1 in addition to histological and immunohistochemical examination of caspase-3 in the adrenal and thyroid glands of adult albino rats. Adult albino rats were divided into 2 groups; group A (drowning) and group B (post-mortem submersion). Thyroid and adrenal glands were examined at different PMI. The results revealed significant differences at AQP1 levels between drowning and postmortem submersion at different PMI. Histological changes and caspase-3 expression immunologically in both glands were helpful.     

Micro computed tomography features of laryngeal fractures in a case of fatal manual strangulation

Cases of subtle fatal neck compression are often complicated by the lack of specificity of the post-mortem signs of asphyxia and by the lack of clear signs of neck compression.Herein we present a forensic case of a 45-year-old schizophrenic patient found on the floor of the bedroom of a psychiatric ward in cardiopulmonary arrest and who died after two days in a vegetative state. The deposition of the roommate of the deceased, who claimed responsibility for the killing of the victim by neck compression, was considered unreliable by the prosecutor.Autopsy, toxicological analyses, and multi-slice computed tomography (MSCT), micro computed tomography (micro-CT) and histology of the larynx complex were performed. Particularly, micro-CT analysis of the thyroid cartilage revealed the bilateral presence of ossified triticeous cartilages and the complete fragmentation of the right superior horn of the thyroid, but it additionally demonstrated a fracture on the contralateral superior horns, which was not clearly diagnosable at MSCT. On the basis of the evidence of intracartilaginous laryngeal hemorrhages and bilateral microfracture at the base of the superior horns of the larynx, the death was classified as a case of asphyxia due to manual strangulation.Micro-CT was confirmed as a useful tool in cases of subtle fatal neck compression, for the detection of minute laryngeal cartilage fractures, especially in complex cases with equivocal findings on MSCT.     

New approach to age estimation of male and female adult skeletons based on the morphological characteristics of the acetabulum

Age estimation is essential to the human identification process, both in forensic and archeological contexts. Based on the previous male-specific method of Rissech et al. (J Forensic Sci, 2006, 51:213–229), a new approach to age estimation based on the acetabulum has been described and evaluated in 611 individuals from the Lisbon Collection (Lisbon, Portugal). This paper has two main goals: (1) to revise and better define the variables of Rissech’s method related to the acetabular fossa, namely, variables 5, 6, and 7, and (2) to extend the applicability of this new approach to both sexes while analyzing age-related sex differences in the acetabular aging process. The results demonstrate the suitability of combining acetabulum traits and a Bayesian approach to estimating age in adults of both sexes. This study has confirmed the usefulness of the redefined variables of the acetabular fossa when age-related changes are considered. Furthermore, the newly defined variables have good to excellent values of repeatability. The study has also extended the method’s applicability to females. The revised method has absolute error averages of 7.28 years for males and 7.09 years for females, based on a sex-specific reference sample. In addition, approximately 74 % of the individuals estimated had an absolute error less than 10 years. Interestingly, the acetabular aging process follows similar trends in both sexes, but the aging rate seems to be different between males and females, especially in middle-aged individuals. Despite the fact that the age estimates, on average, did not improve significantly with the use of a sex-specific reference sample, it is recommended that the sexes be analyzed separately due to the differences in aging rates and inaccuracy values.

     

Reference data for the Thiemann–Nitz method of assessing skeletal age for the purpose of forensic age estimation

The aim of this study was to determine the statistical parameters of deviation in the Thiemann–Nitz method for use in forensic age diagnostics. To this effect, 402 hand radiograms, originally taken in two large German cities between 1983 and 2002 for the purpose of diagnosing trauma, were analyzed. At the time of examination, the patients were aged between 10 and 18 years. The study presents the mean, standard deviation, and median, with lower and upper quartiles, for the skeletal ages of 11.0 through 18.0 years. The simple standard deviations range between 0.2 and 1.2 years. To increase the accuracy of age estimates and improve the identification of age-relevant developmental disorders in forensic age estimation practice, the methods for determining skeletal age should always be combined with a physical and dental examination. In addition, the expert opinion should pay attention to the issue of different modernization levels in relevant populations.     

When the hidden features become evident: The usefulness of PMCT in a strangulation-related death

Asphyxia related-death is a common incident in forensic practice, since they can be related to suicide, homicide and accident. The deep structures of the neck can be very difficult to reach using the traditional neck dissection when no certain information about potential injuries are obtained.Furthermore in this kind of deaths no specific signs or injuries can be found at the external and internal examination of the body (such as the slight, if any, displacement of a body structure following a infraction and fissures, as well as injuries involving lamellae of the thyroid cartilage, cricoid cartilage, trachea). In recent years a great contribute to the field of postmortem diagnostics (e.g. gunshot wounds, sharp and blunt forces, etc.) has been given by the introduction of the post-mortem CT (PMCT); that is becoming a standard procedure performed before the traditional postmortem examination.In cases of asphyxia related-death (with special regards to homicidal strangulation) the PMCT with 3D documentation can be very helpful in revealing injuries on the small structures of the neck, that can be also masked by soft tissues and surrounding bleedings and provides a useful guide for the pathologist to choose the right dissecting technique and avoid artifacts or iatrogenic injury to delicate structures, such as hyoid bone or thyroid cartilage.The case of a homicide by ligature strangulation using two items (electric wire and cotton bed sheet) is presented, in which the PMCT was performed before the autopsy, showing helpful features concerning the mechanism of death.     

Advanced laryngeal cancer: sonographic assessment

Endoscopy permits visualization of the endolaryngeal spread of laryngeal tumors, yet the depth of tumor infiltration often remains unclear. The authors used high-resolution sonography in 37 patients with advanced laryngeal cancer to assess the tumors and the cervical lymph nodes. Sonographic findings were compared to operative and histologic reports. Sonography demonstrated histologically confirmed infiltration into the thyroid (n = 8) and cricoid cartilages (n = 1), preepiglottic space (n = 12), base of the tongue (n = 4), hypopharynx (n = 8), subglottic space (n = 3), and thyroid gland (n = 2). Except for the retrolaryngeal portion of the tumor, sonography was valuable in assessing extralaryngeal spread of advanced cancers. It enabled detection of subclinical lymph node metastases in four patients. Furthermore, invasion of the wall of the carotid artery was found in two patients. For evaluating the endolaryngeal and hypopharyngeal portions of the tumor, endoscopy remains mandatory.     

Computed tomography of the injured larynx.

Computed tomography (CT) permitted a much more detailed appraisal of laryngeal dysfunction in patients with blunt laryngeal trauma (8 cases) and iatrogenic injury caused by radiation therapy (7 cases), surgery (2 cases), or intubation (1 case). In thyroid cartilage fractures, the fragments may be widely displaced. The cricoid ring breaks in two places, frequently involving the signet. CT facilitates diagnosis of the mechanism of injury based on the site and extent of fractures. The patterns of distortion and fibrosis of the laryngeal cartilage following radiation therapy may be manifested as encroachment on the airway, easily mistaken for recurrent tumor or localized edema. Minor distortion probably escapes detection on clinical examination. The authors consider CT the examination of choice in laryngeal injury.     

Development of a methylation marker set for forensic age estimation using analysis of public methylation data and the Agena Bioscience EpiTYPER system

Individual age estimation has the potential to provide key information that could enhance and extend DNA intelligence tools. Following predictive tests for externally visible characteristics developed in recent years, prediction of age could guide police investigations and improve the assessment of age-related phenotype expression patterns such as hair colour changes and early onset of male pattern baldness. DNA methylation at CpG positions has emerged as the most promising DNA tests to ascertain the individual age of the donor of a biological contact trace. Although different methodologies are available to detect DNA methylation, EpiTYPER technology (Agena Bioscience, formerly Sequenom) provides useful characteristics that can be applied as a discovery tool in localized regions of the genome. In our study, a total of twenty-two candidate genomic regions, selected from the assessment of publically available data from the Illumina HumanMethylation 450 BeadChip, had a total of 177 CpG sites with informative methylation patterns that were subsequently investigated in detail. From the methylation analyses made, a novel age prediction model based on a multivariate quantile regression analysis was built using the seven highest age-correlated loci of ELOVL2, ASPA, PDE4C, FHL2, CCDC102B, C1orf132 and chr16:85395429. The detected methylation levels in these loci provide a median absolute age prediction error of ±3.07 years and a percentage of prediction error relative to the age of 6.3%. We report the predictive performance of the developed model using cross validation of a carefully age-graded training set of 725 European individuals and a test set of 52 monozygotic twin pairs. The multivariate quantile regression age predictor, using the CpG sites selected in this study, has been placed in the open-access Snipper forensic classification website.     

Forensische Radiologie

Forensic radiology includes both clinical and postmortem forensic radiology. Clinical forensic radiology deals with imaging of healthy people from a legal point of view, such as for determining age or to prove and document injuries in victims of crime. Postmortem forensic radiology deals with the application of modern radiological methods in order to optimise post-mortem diagnosis. X-ray examination has for decades been routinely used in postmortem diagnosis. Newer developments include the application of postmortem computer tomography and magnetic resonance imaging; these are the methods with the greatest information potential but also with the greatest deviations from diagnostics in living persons. Application of radiological methods for securing evidence in criminal procedures is still in its infancy. Radiologists' technical understanding and forensic doctors' knowledge of postmortem changes in a corpse must be synergised.