Quantitative morphological analysis framework of infant cranial sutures and fontanelles based on CT images.

Characterizing the suture morphological variation is a crucial step to investigate the influence of sutures on infant head biomechanics. This study aimed to establish a comprehensive quantitative framework for accurately capturing the cranial suture and fontanelle morphologies in infants. A total of 69 CT scans of 2-4 month-old infant heads were segmented to identify semilandmarks at the borders of cranial sutures and fontanelles. Morphological characteristics, including length, width, sinuosity index (SI), and surface area, were measured. For this, an automatic method was developed to determine the junction points between sutures and fontanelles, and thin-plate-spline (TPS) was utilized for area calculation. Different dimensionality reduction methods were compared, including nonlinear and linear principal component analysis (PCA), as well as deep-learning-based variational autoencoder (VAE). Finally, the significance of various covariates was analyzed, and regression analysis was performed to establish a statistical model relating morphological parameters with global parameters. This study successfully developed a quantitative morphological framework and demonstrate its application in quantifying morphologies of infant sutures and fontanelles, which were shown to significantly relate to global parameters of cranial size, suture SI, and surface area for infants aged 2-4 months. The developed framework proved to be reliable and applicable in extracting infant suture morphology features from CT scans. The demonstrated application highlighted its potential to provide valuable insights into the morphologies of infant cranial sutures and fontanelles, aiding in the diagnosis of suture-related skull fractures. Infant suture, Infant fontanelle, Morphological variation, Morphology analysis framework, Statistical model.

Retinal haemorrhage in infants investigated for suspected maltreatment is strongly correlated with intracranial pathology.

AIM: To test the two prevailing hypotheses regarding the aetiology of infant retinal haemorrhage: (a) traction forces exerted by the lens and/or corpus vitreum on the retina during infant shaking or (b) retinal vessel leakage secondary to intracranial pathology and raised intracranial pressure. METHODS: Comparison of medical findings and reported type of trauma in infants investigated for suspected physical abuse with presence (n = 29) or non-presence of retinal haemorrhage (RH) (n = 119). RESULTS: Intracranial pathology was recorded in 15 (13%) of the non-RH cases and in 27 (97%) of the RH cases (p < 0.0001). All 18 infants with bilateral RH had intracranial pathology. Of 27 infants subjected to witnessed or admitted shaking, two were in the group with RH. One had a single unilateral RH and no intracranial pathology. The other had bilateral RH and intracranial pathology with non-specific white matter changes, acute subdural and subarachnoid haemorrhages, and suspected cortical venous thrombosis. In 15 RH cases, there was no trauma reported and no findings other than RH and intracranial pathology. Accidental blunt head trauma was reported in 7 RH cases. CONCLUSION: The present study indicates that RH in infants is secondary to intracranial pathology of non-specific aetiology.

Drug-related deaths: Statistics based on death certificates miss one-third of cases.

Aims: Statistics on drug-related deaths (DRD) provide crucial information on the drug situation. The European Monitoring Centre for Drug and Drug Addiction (EMCDDA) has published a specification for extracting DRD from national mortality registers to be used in international comparisons. However, surprisingly little is known of the accuracy of DRD statistics derived from national mortality registers. This study assesses the accuracy of Swedish data derived from national mortality registers by comparing it with other sources of data. Methods: We compared five Swedish datasets. Three were derived from national mortality registers, two according to a Swedish specification and one according to the EMCDDA specification. A fourth dataset was based on toxicological analyses. We used a fifth dataset, an inventory of DRD in Stockholm, to assess the completeness and coverage of the Swedish datasets. Results: All datasets were extracted from high-quality registers, but still did not capture all DRD, and both the numbers and demographic characteristics varied considerably. However, the time trends were consistent between the selections. In international comparisons, data completeness and investigation procedures may impact even more on stated numbers. Conclusions: Basing international comparisons on numbers or rates of DRDs gives misleading results, but comparing trends is still meaningful.

Difficult birth is the main contributor to birth-related fracture and accidents to other neonatal fractures.

AIM: Specific birth-related fractures have been studied; underestimates might be a problem. We aimed to assess all fractures diagnosed as birth-related as well as other neonatal fractures. METHODS: A population-based study on all infants born in Sweden 1997-2014; data were retrieved from the Swedish Health Registers (10th version of International Classification of Diseases. Outcome measures were birth-related fractures (ICD-10 P-codes) and other neonatal fractures (ICD-10 S-codes). RESULTS: The overall fracture incidence was 2.9 per 1000 live birth (N = 5336); 92.6% had P-codes and 7.4% (S-codes). Some birth-related fractures were diagnosed beyond the neonatal period. Other neonatal fractures could have been birth-related. Clavicle fracture (88.8%) was associated with adverse maternal and infant anthropometrics and birth complications. The few neonates with rib fractures all had concomitant clavicle fracture. For skull fractures, a minor part was birth-related and most were associated with accidents. Half of the long bone fractures were associated with accidents. Birth-related femur fractures were associated with bone fragility risk factors. Five infants with abuse diagnoses had fractures: skull (4), long bone (2) and rib (1). CONCLUSION: Birth-related and other neonatal fractures are rarely diagnosed. Difficult birth is the main contributor to birth-related fracture and accidents to other neonatal fractures.

The epidemiology of infant shaft fractures of femur or humerus by incidence, birth, accidents, and other causes.

BACKGROUND: The purpose of this population-based registry study was to analyze both birth-related femur and humerus shaft fractures and diagnosed later in infancy, as regards incidence, perinatal characteristics, other diagnoses, and reported accidents. METHODS: Children born in 1997-2014, diagnosed with a femur or humerus shaft fracture before age 1 year, were identified in the Swedish Health Registries. Rate of birth fractures were estimated by combining femur and humerus shaft fractures coded as birth-related with femur and humerus shaft fractures diagnosed during day 1-7 without registered trauma or abuse. Incidence was computed by comparing infants with femur or humerus shaft fractures to the total at-risk population. RESULTS: The incidence for birth-related femur shaft fractures was 0.024 per 1000 children (n = 45) and that for birth-related humerus shaft fractures was 0.101 per 1000 children (n = 188). The incidence was 0.154 per 1000 children for later femur shaft fractures (n = 287) and 0.073 per 1000 children for later humerus shaft fractures (n = 142). Birth-related femur shaft fracture was associated with shoulder dystocia, cesarean, multiple birth, breech, preterm, and small-for-gestational age, while humerus shaft fracture was associated with maternal obesity, dystocic labor, shoulder dystocia, vacuum-assisted delivery, male sex, multiple birth, breech, preterm, large-for-gestational age, birth weight > 4000 g, and injury of brachial plexus. A bone fragility diagnosis was recorded in 5% of those with birth-related or later femur shaft fractures. Among infants with birth-related humerus shaft fractures, 1% had a bone fragility diagnosis; the figure for later fractures was 6%. Maltreatment diagnosis was associated with later fractures of both types, especially among those aged < 6 months, where approximately 20% (femur) and 14% (humerus) of cases, respectively, were associated with abuse. Fall accidents were reported in 73 and 56% among those with later femur and humerus shaft fractures, respectively. CONCLUSION: This study provides data on epidemiology, birth, parental characteristics, and reported accidents in relation to femur and humerus shaft fractures during infancy. Few children had a bone fragility diagnosis. Fall accidents were the main contributor to femur or humerus shaft fracture during infancy; however, the proportion of fractures attributed to maltreatment was high in children under 6 months.

Psychoactive substances in natural and unnatural deaths in Norway and Sweden - a study on victims of suicide and accidents compared with natural deaths in psychiatric patients.

BACKGROUND: The extent of post-mortem detection of specific psychoactive drugs may differ between countries, and may greatly influence the national death register's classification of manner and cause of death. The main objective of the present study was to analyse the magnitude and pattern of post-mortem detection of various psychoactive substances by the manner of death (suicide, accidental, undetermined and natural death with a psychiatric diagnosis) in Norway and Sweden. METHODS: The Cause of Death Registers in Norway and Sweden provided data on 600 deaths in 2008 from each country, of which 200 were registered as suicides, 200 as accidents or undetermined manner of death and 200 as natural deaths in individuals with a diagnosis of mental disorder as the underlying cause of death. We examined death certificates and forensic reports including toxicological analyses. RESULTS: The detection of psychoactive substances was commonly reported in suicides (66 and 74% in Norway and Sweden respectively), accidents (85 and 66%), undetermined manner of deaths (80% in the Swedish dataset) and in natural deaths with a psychiatric diagnosis (50 and 53%). Ethanol was the most commonly reported substance in the three manners of death, except from opioids being more common in accidental deaths in the Norwegian dataset. In cases of suicide by poisoning, benzodiazepines and z-drugs were the most common substances in both countries. Heroin or morphine was the most commonly reported substance in cases of accidental death by poisoning in the Norwegian dataset, while other opioids dominated the Swedish dataset. Anti-depressants were found in 22% of the suicide cases in the Norwegian dataset and in 29% of suicide cases in the Swedish dataset. CONCLUSIONS: Psychoactive substances were detected in 66 and 74% of suicides and in 85 and 66% of accidental deaths in the Norwegian and Swedish datasets, respectively. Apart from a higher detection rate of heroin in deaths by accident in Norway than in Sweden, the pattern of detected psychoactive substances was similar in the two countries. Assessment of a suicidal motive may be hampered by the common use of psychoactive substances in suicide victims.

Infant abuse diagnosis associated with abusive head trauma criteria: incidence increase due to overdiagnosis?

Background: The hypothesis of this study is that the diagnosis of infant abuse is associated with criteria for shaken baby syndrome (SBS)/abusive head trauma (AHT), and that that changes in incidence of abuse diagnosis in infants may be due to increased awareness of SBS/AHT criteria. Methods: This was a population-based register study. Setting: Register study using the Swedish Patient Register, Medical Birth Register, and Cause of Death Register. The diagnosis of infant abuse was based on the International Classification of Diseases, 9th and 10th revision. Participants: All children born in Sweden during 1987-2014 with a follow-up until 1 year of age (N = 2 868 933). SBS/AHT criteria: subdural haemorrhage, cerebral contusion, skull fracture, convulsions, retinal haemorrhage, fractures rib and long bones. Outcomes: Incidence, rate ratios, aetiologic fractions and Probit regression analysis. Results: Diagnosis of infant abuse was strongly associated with SBS/AHT criteria, but not risk exposure as region, foreign-born mother, being born preterm, multiple birth and small for gestational age. The incidence of infant abuse has increased tenfold in Sweden since the 1990s and has doubled since 2008, from 12.0 per 100 000 infants during 1997-2007 to 26.5/100 000 during 2008-2014, with pronounced regional disparities. Conclusions: Diagnosis of infant abuse is related to SBS/AHT criteria. The increase in incidence coincides with increased medical preparedness to make a diagnosis of SBS/AHT. Hidden statistics and a real increase in abuse are less plausible. Whether the increase is due to overdiagnosis cannot be answered with certainty, but the possibility raises ethical and medico-legal concerns.

National study shows that abusive head trauma mortality in Sweden was at least 10 times lower than in other Western countries.

AIM: The validity of the diagnostic criteria for abusive head trauma (AHT) and its attributes has been widely debated. This national study investigated the possibility of false-positive and false-negative cases of fatal AHT in Sweden. METHOD: This was a retrospective evaluation of the records of 733 deceased infants up to the age of 365 days who were examined during 1994-2013 at the six forensic medicine departments. All the records were scrutinised for possible cases of AHT. RESULTS: We included 12 cases, of which eight had been diagnosed as AHT. Of these 12 infants, eight had a concomitant disease or perinatal illness, five were born prematurely and three were twins. Figures from other Western countries would suggest 6-7 deaths per 100,000 per year in Sweden, but in reality, there was a maximum possible incidence of 0.6 per 100,000 infants per year. CONCLUSION: The risk of unreported fatal AHT in Sweden was low, and there may have been cases misdiagnosed as AHT. The at least 10 times lower incidence than has been reported from other Western countries, raises the question if previously reported higher incidences of fatal AHT have been exaggerated.

Accidents and undetermined deaths: re-evaluation of nationwide samples from the Scandinavian countries.

BACKGROUND: National mortality statistics should be comparable between countries that use the World Health Organization's International Classification of Diseases. Distinguishing between manners of death, especially suicides and accidents, is a challenge. Knowledge about accidents is important in prevention of both accidents and suicides. The aim of the present study was to assess the reliability of classifying deaths as accidents and undetermined manner of deaths in the three Scandinavian countries and to compare cross-national differences. METHODS: The cause of death registers in Norway, Sweden and Denmark provided data from 2008 for samples of 600 deaths from each country, of which 200 were registered as suicides, 200 as accidents or undetermined manner of deaths and 200 as natural deaths. The information given to the eight experts was identical to the information used by the Cause of Death Register. This included death certificates, and if available external post-mortem examinations, forensic autopsy reports and police reports. RESULTS: In total, 69 % (Sweden and Norway) and 78 % (Denmark) of deaths registered in the official mortality statistics as accidents were confirmed by the experts. In the majority of the cases where disagreement was seen, the experts reclassified accidents to undetermined manner of death, in 26, 25 and 19 % of cases, respectively. Few cases were reclassified as suicides or natural deaths. Among the extracted accidents, the experts agreed least with the official mortality statistics concerning drowning and poisoning accidents. They also reported most uncertainty in these categories of accidents. In a second re-evaluation, where more information was made available, the Norwegian psychiatrist and forensic pathologist increased their agreement with the official mortality statistics from 76 to 87 %, and from 85 to 88 %, respectively, regarding the Norwegian and Swedish datasets. Among the extracted undetermined deaths in the Swedish dataset, the two experts reclassified 22 and 51 %, respectively, to accidents. CONCLUSION: There was moderate agreement in reclassification of accidents between the official mortality statistics and the experts. In the majority of cases where there was disagreement, accidents were reclassified as undetermined manner of death, and only a small proportion as suicides.

Suicide or undetermined intent? A register-based study of signs of misclassification.

BACKGROUND: Several studies have concluded that some deaths classified as undetermined intent are in fact suicides, and it is common in suicide research in Europe to include these deaths. Our aim was to investigate if information on background variables would be helpful in assessing if deaths classified as undetermined intent should be included in the analyses of suicides. METHODS: We performed a register study of 31,883 deaths classified as suicides and 9,196 deaths classified as undetermined intent in Sweden from 1987 to 2011. We compared suicide deaths with deaths classified as undetermined intent with regard to different background variables such as sex, age, country of birth, marital status, prior inpatient care for self-inflicted harm, alcohol and drug abuse, psychiatric inpatient care, and use of psychotropics. We also performed a multivariate analysis with logistic regression. RESULTS: Our results showed differences in most studied background factors. Higher education was more common in suicides; hospitalization for self-inflicted harm was more common among female suicides as was prior psychiatric inpatient care. Deaths in foreign-born men were classified as undetermined intent in a higher degree and hospitalization for substance abuse was more common in undetermined intents of both sexes. Roughly 50% of both suicide and deaths classified as undetermined intent had a filled prescription of psychotropics during their last six months. Our multivariate analysis showed male deaths to more likely be classified as suicide than female: OR: 1.13 (1.07-1.18). The probability of a death being classified as suicide was also increased for individuals aged 15-24, being born in Sweden, individuals who were married, and for deaths after 1987-1992. CONCLUSION: By analyzing Sweden's unique high-validity population-based register data, we found several differences in background variables between deaths classified as suicide and deaths classified as undetermined intent. However, we were not able to clearly distinguish these two death manners. For future research we suggest, separate analyses of the two different manners of death.

The role of alternative hypotheses in reducing bias in forensic medical experts' decision making.

Medical opinions are often essential evidence in criminal cases but relatively little is known about the factors that impact forensic doctors' decision making. This research examines the role and impact of having an alternative hypothesis while forming a medical opinion. A scenario-based experiment with forensic doctors (n = 20) was conducted. In two out of three scenarios, the existence of alternative hypotheses impacted the actual opinions reached, the confidence in the judgments and the perceived consistency with the plaintiff hypothesis. Investigative and legal actors should be aware of the possibility of biases and importance of having alternative hypotheses when requesting and evaluating medical opinions.

External Hydrocephalus as a Cause of Infant Subdural Hematoma: Epidemiological and Radiological Investigations of Infants Suspected of Being Abused.

BACKGROUND: Acute subdural hematoma (ASDH) and chronic subdural hematoma (CSDH) in infants have been regarded as highly specific for abuse. Other causes of CSDH have not been investigated in a large population. PURPOSE: The purpose of this study was to investigate to what extent external hydrocephalus is present in infants with ASDH and CSDH undergoing evaluation for abuse. MATERIAL AND METHODS: Eighty-five infants suspected of being abused, with ASDH (n = 16) or CSDH (n = 69), were reviewed regarding age, risk factor profiles, craniocortical width (CCW), sinocortical width (SCW), frontal interhemispheric width (IHW), subarachnoid space width (SSW), and head circumference (HC). In infants with unilateral subdural hematoma (SDH), correlations between contralateral SSW and ipsilateral CCW and SDH width were investigated. RESULTS: Infants with CSDH had significantly lower mortality, were more often premature and male, and had significantly higher CCW, SCW, IHW, and SSW than infants with ASDH (P < 0.05). Ipsilateral CCW (R = 0.92, P < 0.001) and SDH width (R = 0.81, P < 0.01) correlated with contralateral SSW. Increased HC was more prevalent in infants with CSDH (71%) than in infants with ASDH (14%) (P < 0.01). Forty-two infants, all with CSDH, had at least one of CCW, SCW, or IHW ≥95th percentile. Twenty infants, all with CSDH, had CCW, SCW, and IHW >5 mm, in addition to increased HC. CONCLUSION: A substantial proportion of infants with CSDH who had been suspected of being abused had findings suggesting external hydrocephalus.

Rib fractures in infancy, case-series and register case-control study from Sweden.

OBJECTIVES: To assess cases with rib fractures in infants under observation for or with an abuse diagnosis, and to compare risk factors with that in infants with fractures but no abuse diagnosis. METHODS: Design was case-series and register case-control of infants (aged <1 year) with rib fractures. Data was clinical records for the case-series (n = 26) and from national health registers for the case-controls (n = 28 and n = 31). Outcome measures were maternal and perinatal characteristics, reasons for appointment, examination, diagnoses, blood tests, and radiologic findings. RESULTS: The case-series had a median age of 70 days. A majority were detected through a skeletal survey for abuse investigation. Sixteen were boys, three were preterm and six were small-for-gestational age. Three carers had noticed popping sound from the chest; no infants showed signs of pain at physical examination. Mean number of fractures was 4.2, and 24 had callus. Bone mineralisation was scarcely reported. Metabolic panel was not uniformly analysed. The register case-control had a median age of 76 days, sharing risk factors such as maternal overweight/obesity, male sex, prematurity, and being small-for-gestational age. Cases more often had subdural haemorrhage, retinal haemorrhage, or long-bone fractures, controls more often had neonatal morbidity, respiratory infection, or a fall accident. Detection of fracture at time of a major surgery (n = 6) and rickets/vitamin D deficiency (n = 5) appeared in both groups, but was delayed among the cases. CONCLUSIONS: Rib fractures in young infants, diagnosed as abuse, are usually asymptomatic and healing. A substantial proportion had metabolic risk factors, suggesting false positive cases.

A model for evaluating the economic value of prevention programs for illicit use of anabolic androgenic steroids.

BACKGROUND: The illicit use of anabolic androgenic steroids (AAS) has become a societal concern. We developed a decision-analytic model for assessing the cost-effectiveness of preventive interventions targeting AAS-use. We used scenario analyses to demonstrate: a) the potential health economic consequences of AAS use in Sweden, and b) the cost-effectiveness of a hypothetical preventive intervention. METHODS: A population-based cohort model compared a hypothetical preventive intervention targeting AAS with a 'no intervention' scenario, from a limited societal perspective. The model simulated how a cohort of 18 year-old males transitioned between different states and predicted their health status and complications until the age of 41. Health outcomes were estimated as quality-adjusted life-years (QALY). Costs included intervention costs, drug costs, and costs of complications. RESULTS: Total yearly costs related to AAS use amounted to nearly half a million US$, with the largest cost borne by the healthcare sector. Results suggest that AAS prevention could entail large costs and benefits with a mean incremental cost-effectiveness ratio of $550 per QALY, in a scenario where the intervention would decrease the probability of initiating AAS use by 5%. CONCLUSION: Results show large AAS related costs, and suggest that the implementation of a preventive intervention could offer good value for money given different effectiveness scenarios. This model can be used to estimate the value of interventions targeting AAS use.

Characteristics of post-mortem beta-hydroxybutyrate-positivet cases - A retrospective study on age, sex and BMI in 1407 forensic autopsies.

BACKGROUND: Post-mortem biochemistry, including the analysis of beta-hydroxybutyrate (BHB), is increasingly employed in forensic medicine, especially in conditions such as diabetes and chronic alcoholism. However, not much is known about the associations between age, body mass index (BMI), and sex and BHB concentrations in ketoacidotic conditions. AIM: To retrospectively study the association between age, BMI and sex in several conditions, such as diabetic ketoacidosis (DKA), alcoholic ketoacidosis (AKA), and elevated post-mortem BHB concentrations. METHODS: 1407 forensic autopsy cases analysed for BHB were grouped by diagnosis: DKA, AKA, HHS [hyperosmolar hyperglycaemic state], acidosis NOS [not otherwise specified], or hypothermia. Age, sex, BMI and the concentrations of blood alcohol, vitreous glucose and blood BHB were recorded. RESULTS: Cases of AKA and DKA were most numerous (184 and 156, respectively). In DKA and in its male subgroup, cases with severe ketosis (BHB>1000 µg/g) were younger and had a lower BMI than those with moderate ketosis (BHB 250-1000 µg/g) and controls (P<0.001). In DKA and in its female subgroup, cases with moderate ketosis cases were older (P = 0.0218 and P = 0.0083) than controls. In AKA and in its male subgroup, cases with severe ketosis had a lower BMI than those with moderate ketosis (P = 0.0391 and P = 0.0469) and controls (P<0.001). Cases with moderate ketosis had a lower BMI than controls (P<0.001). CONCLUSIONS: BHB concentration is associated with BMI in DKA and AKA, and with both BMI and age in DKA. Constitutional factors should, therefore, be considered in potential AKA and DKA cases.