Abusive head trauma (AHT) is frequently accompanied by dense/extensive retinal hemorrhages to the periphery with or without retinoschisis (complex retinal hemorrhages, cRH). cRH are uncommon without AHT or major trauma.

The study objectives were to determine whether cRH are associated with inertial vs. contact mechanisms and are primary vs. secondary injuries.

This retrospective study utilized a de-identified PediBIRN database of 701 children <3-years-old presenting to intensive care for head trauma. Children with motor vehicle related trauma and preexisting brain abnormalities were excluded. All had imaging showing head injury and a dedicated ophthalmology examination.

Contact injuries included craniofacial soft tissue injuries, skull fractures and epidural hematoma. Inertial injuries included acute impairment or loss of consciousness and/or bilateral and/or interhemispheric subdural hemorrhage. Abuse was defined in two ways, by 1) predetermined criteria and 2) caretaking physicians/multidisciplinary team's diagnostic consensus.

PediBIRN subjects with cRH frequently experienced inertial injury (99.4 % (308/310, OR = 53.74 (16.91-170.77)) but infrequently isolated contact trauma (0.6 % (2/310), OR = 0.02 (0.0004-0.06)). Inertial injuries predominated over contact trauma among children with cRH sorted AHT by predetermined criteria (99.1 % (237/239), OR = 20.20 (6.09-67.01) vs 0.5 % (2/339), OR = 0.04 (0.01-0.17)). Fifty-nine percent of patients with cRH, <24 h altered consciousness, and inertial injuries lacked imaging evidence of brain hypoxia, ischemia, or swelling.

cRH are significantly associated with inertial angular acceleration forces. They can occur without brain hypoxia, ischemia or swelling suggesting they are not secondary injuries.

Pediatric abusive head trauma (AHT), still colloquially known as shaken baby syndrome, is a leading cause of morbidity and mortality among infants. Controversy has grown surrounding this diagnosis, and the specificity of the clinical findings-subdural hemorrhage, cerebral edema, and retinal hemorrhages-has been challenged. A literature search of peer reviewed publications on PubMed pertaining to the history, clinical, and pathologic features of AHT was conducted using the terms "shaken baby syndrome," "non-accidental trauma," "abusive head trauma," "inflicted traumatic brain injury," "shaken impact syndrome," and "whiplash shaken infant syndrome." Focus was placed on articles discussing ophthalmic findings in AHT. Retinal hemorrhages-particularly those that are too numerous to count, occurring in all layers of the retina (preretinal, intraretinal, subretinal), covering the peripheral pole and extending to the ora serrata, and accompanied by retinoschisis and other ocular/periocular hemorrhages-are highly suggestive of AHT, particularly in the absence of otherwise explained massive accidental trauma. Although the diagnosis has grown in controversy in recent years, AHT has well-documented clinical and pathologic findings across a large number of studies.

Epilepsy is the most common neurologic disorder which is further complicated by neurobehavioral co-morbidities, cognitive impairment, psychiatric disorders, and social problems. However, assessments of cognitive status of epileptic patients are far too low during clinical visits. This calls for early neuropsychological assessment soon after the diagnosis of epilepsy for a better treatment plan and outcome for epileptic patients.

This study aimed to assess the cognitive adverse effects of epilepsy and its predictors attending outpatient departments of South Gondar Zone hospitals Amhara region Ethiopia 2020/2021.

A multi-center institutional-based cross-sectional study was conducted. A total of 509 respondents were included with a response rate of 93.9%. Previously adapted pretested structured questionnaire was used containing, socio-demographic, clinical, and seizure related factors. Mini-Mental State Examination (MMSE) was used to measure cognitive impairment. A systematic random sampling technique was applied. Data were entered into Epi data version 4.4.2 then exported to SPSS version 24 for analysis. Descriptive statistics, bivariable and multivariable binary logistic regressions with odds ratios and 95% confidence interval were employed. The level of significance of association was determined at a p-value < 0.05.

Prevalence of cognitive impairment in this study was 69.2% (95%CI; 65.4, 73.1). Rural residents (AOR = 4.16,95%CI, 1.99,8.67), respondents who couldn't read and write (AOR = 2.62, 95%CI; 1.24, 5.5,) longer duration of seizure disorder (AOR = 4.59,95%CI; 2.01,10.52), taking combined Phenobarbital and Phenytoin (AOR = 4.69,95%CI; 1.88,11.69), having history of head injury (AOR = 3.29,95%CI;1.30,8.32), having depression (AOR = 4.76,95%CI;2.83,7.98), and anxiety (AOR = 3.11,95%CI; 1.58,6.12) were significantly associated with cognitive impairment.

Prevalence of cognitive impairment in this study was high. Regular neuropsychiatric assessment of patients with epilepsy should be encouraged especially for those participants with longer durations of illness, who are rural residents, who take combined Phenobarbital and Phenytoin, participants who had a history of head injury, depression, and anxiety.

The combination of bridging vein rupture/thrombosis and subdural hematoma in infants has recently gained attention as highly suggestive of abusive head trauma. While subdural hematomas are frequently observed at birth, there are no previous studies of bridging vein rupture/thrombosis prevalence in that context.

To evaluate the prevalence of bridging vein rupture/thrombosis in newborns with and without subdural hematoma.

This bicentric retrospective study (2012-2019) looked at all brain MRIs performed in neonates. We noted delivery method, demographic data and intracranial injuries and analyzed any clots at the vertex as potential markers of bridging vein rupture/thrombosis.

We analyzed 412 MRIs in 412 neonates. Age was (mean ± standard deviation [SD]) 5.4±2.2 days and 312 (76%) infants were full term (38.3±2.9 weeks from last menstrual period). The delivery method was vaginal birth for 42% (n=174), cesarean section for 43% (n=179), and unknown for 14% (n=59). Subdural hematoma was present in 281 MRIs (68.0%, [95% confidence interval = 63.3-72.5]). Six MRIs showed at least one clot at the vertex, assumed to be possible bridging vein rupture/thrombosis (1.5%, [0.5-3.1%]). Only one MRI showed more than two clots at the vertex, in a context of maternal infection. There was no significant difference in terms of gestational age at birth, delivery method or the presence of subdural hematoma or parenchymal injuries between those 6 infants and the 406 others.

Bridging vein rupture/thrombosis at birth is very rare and unlikely to be related to subdural hematoma.

The author responds to critics formulated by W Squier regarding our paper "The legal challenges to the diagnosis of shaken baby syndrome Or: how to counter 12 common fake news.

The shaken baby syndrome (SBS) is a common cause of severe traumatic lesions in infants. Although well established for almost five decades, SBS and its diagnosis are becoming more and more aggressively challenged in courts. These challenges feed on the scientific debate and controversies regarding the pathophysiology and the differential diagnoses, scientific uncertainty being readily exploited by specialized barristers.

In the present review, we analyze the most common challenges to the concept of SBS and its diagnosis, as well as the scientific evidence available to counter these challenges, the differential diagnoses, and how SBS can be diagnosed with confidence.

We found that the pathophysiology of SBS is well documented, with stereotyped descriptions by perpetrators, in good correlation with experimental studies and computer models. SBS is a well-defined clinico-pathological entity with a characteristic constellation of lesions; with a rigorous evaluation protocol, its diagnosis can be made rapidly and with excellent accuracy beyond a reasonable doubt.

It is important that medical experts master an extensive knowledge regarding the pathophysiology of the lesions of SBS, in particular infantile subdural hematomas, as well as other CSF-related conditions. This emphasizes the role that pediatric neurosurgeons should play in the clinical and medicolegal management of these patients.

Child abuse is a global public health concern. Injuries from physical abuse may be clinically occult and not appreciable on physical examination. Imaging is therefore critical in identifying and documenting such injuries. The radiologic approach for a child who has potentially been abused has received considerable attention and recommendations according to decades of experience and rigorous scientific study. Nonetheless, fringe beliefs describing alternative explanations for child abuse-related injuries have emerged and received mainstream attention. Subsequently, imaging findings identified in abused children have been attributed to poorly supported underlying medical conditions, clouding the evidence basis for radiologic findings indicative of nonaccidental trauma. Fringe beliefs that attribute findings seen in child abuse to alternate pathologies such as genetic disorders, birth trauma, metabolic imbalances, vitamin D deficiency, and short-distance falls typically have limited evidence basis and lack professional society support. Careful review of the scientific evidence and professional society consensus statements is important in differentiating findings attributable to child abuse from fringe beliefs used to discount the possibility that a child's constellation of injuries is consistent with abuse. This review refutes fringe beliefs used to provide alternative explanations in cases of suspected child abuse and reinforces the key literature and scientific consensus regarding child abuse imaging.

The diagnosis of abusive head trauma (AHT) is complex and neuroimaging plays a crucial role. Our goal was to determine whether non-neuroradiologists with standard neuroradiology knowledge perform as well as neuroradiologists with experience in pediatric neuroimaging in interpreting MRI in cases of presumptive AHT (pAHT).

Twenty children were retrospectively evaluated. Patients had been diagnosed with pAHT (6 patients), non-abusive head trauma-NAHT (5 patients), metabolic diseases (3 patients), and benign enlargement of the subarachnoid spaces (BESS) (6 patients). The MRI was assessed blindly, i.e., no clinical history was given to the 3 non-neuroradiologists and 3 neuroradiologists from 2 different institutions.

Blindly, neuroradiologists demonstrated higher levels of sensitivity and positive predictive value in the diagnosis of pAHT (89%) than non-neuroradiologists (50%). Neuroradiologists chose correctly pAHT as the most probable diagnosis 16 out of 18 times; in contrast, non-neuroradiologists only chose 9 out of 18 times. In our series, the foremost important misdiagnosis for pAHT was NAHT (neuroradiologists twice and non-neuroradiologists 5 times). Only victims of motor vehicle accidents were blindly misdiagnosed as pAHT. No usual household NAHT was not misdiagnosed as pAHT. Neuroradiologists correctly ruled out pAHT in all cases of metabolic diseases and BESS.

MRI in cases of suspected AHT should be evaluated by neuroradiologists with experience in pediatric neuroimaging. Neuroradiologists looked beyond the subdural hemorrhage (SDH) and were more precise in the assessment of pAHT and its differential diagnosis than non-neuroradiologists were. It seems that non-neuroradiologists mainly assess whether or not a pAHT is present depending on the presence or absence of SDH.

To analyze factors for cognitive impairment in epileptic patients.

A total of 257 epileptic patients completed clinical memory scale (CMS) and 70 of them were further surveyed with mini-mental state examination (MMSE), Montreal cognitive assessment (MoCA), digital symbol test (DSy), verbal fluency test, digit span test (DSp), Hamilton anxiety scale (HAMA) and Hamilton depression scale (HAMD). Monadic linear related analysis and multiple stepwise regression analysis were performed to evaluate the potential factors for cognitive impairment.

Educational level was correlated with scores of cognitive tests (p < .01), with a difference between the junior high school group and senior high school group (p < .01 or p < .05). Seizure frequency was negatively correlated with CMS scores (p < .01), with a difference between the group with a seizure frequency of less than once a year and other groups (p < .01). The kind of antiepileptic drugs (AEDs) was negatively correlated with CMS scores (p < .01), with a difference between the single-drug group and the group taking more than two kinds of AEDs (p < .01). Depression scores were negatively correlated with MMSE, MoCA, DSy, DSp (p < .01 or p < .05), disease duration negatively with DSy (p < .01), and age negatively with MoCA (p < .05). Seizure type was correlated with DSy, and general seizure fared worse in the tests than other seizure types (p < .05).

Educational level, seizure frequency, kinds of AEDs and depression can affect the cognitive function of epileptic patients. High educational level, good seizure control, single-drug treatment and healthy psychological state are protective factors for cognitive function of epileptic patients.

Hypoxic-ischemic injuries (HIIs) are a scarcely investigated but important cause of morbidity and mortality in children who suffered abusive head trauma (AHT). The purpose of this study is to determine: (a) prevalence, types, and clinical relevance of cytotoxic edema compatible with HII in nonpenetrating AHT, (b) their relationship to other classic neuroimaging findings of AHT, and (c) their correlation with clinical outcomes.

Diffusion-weighted imaging sequences of magnetic resonance imagings performed on children under 5 years diagnosed with AHT were reviewed to detect the most common patterns of acute parenchymal damage. Patterns of cytotoxic edema were described, and HII-compatible ones divided in subtypes. Correlation between HII, fractures, and subdural hemorrhages (SDHs) and with clinical outcomes was determined using imaging and available follow-up data.

Out of 57 patients, 36.8% showed lesions compatible with HII. A predominantly asymmetric cortical distribution was observed in 66.7% of cases, while 33.3% had diffused both cortical and deep gray/white matter distribution injury. Traumatic axonal injuries and focal contusions were less common. There was no significant correlation between the presence of SDH (P = .6) or skull fractures (P = .53) and HII. HII was the most severe form of parenchymal damage in terms of in-hospital mortality and morbidity at follow-up.

HII is the most common type of parenchymal damage in children victim of AHT, being present in 1/3 of patients with this condition, and correlates with more severe outcomes. Its presence is independent from other classic traumatic findings such as SDH and fractures.

Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. A multidisciplinary team bases this diagnosis on history, physical examination, imaging and laboratory findings. Because the etiology of the injury is multifactorial (shaking, shaking and impact, impact, etc.) the current best and inclusive term is AHT. There is no controversy concerning the medical validity of the existence of AHT, with multiple components including subdural hematoma, intracranial and spinal changes, complex retinal hemorrhages, and rib and other fractures that are inconsistent with the provided mechanism of trauma. The workup must exclude medical diseases that can mimic AHT. However, the courtroom has become a forum for speculative theories that cannot be reconciled with generally accepted medical literature. There is no reliable medical evidence that the following processes are causative in the constellation of injuries of AHT: cerebral sinovenous thrombosis, hypoxic-ischemic injury, lumbar puncture or dysphagic choking/vomiting. There is no substantiation, at a time remote from birth, that an asymptomatic birth-related subdural hemorrhage can result in rebleeding and sudden collapse. Further, a diagnosis of AHT is a medical conclusion, not a legal determination of the intent of the perpetrator or a diagnosis of murder. We hope that this consensus document reduces confusion by recommending to judges and jurors the tools necessary to distinguish genuine evidence-based opinions of the relevant medical community from legal arguments or etiological speculations that are unwarranted by the clinical findings, medical evidence and evidence-based literature.

The cause of death in infants who die suddenly and unexpectedly (sudden unexpected death in infancy [SUDI]) remains a diagnostic challenge. Some infants have identified diseases (explained SUDI); those without explanation are called sudden infant death syndrome (SIDS). Demographic data indicate subgroups among SUDI and SIDS cases, such as unsafe sleeping and apparent life-threatening events. Infants dying suddenly with retinal and dural bleeding are often classified as abused, but in many there is no evidence of trauma. Demographic features suggest that they may represent a further subgroup of SUDI. This review examines the neuropathological hypotheses to explain SIDS and highlights the interaction of infant oxygen-conserving reflexes with the brainstem networks considered responsible for SIDS. We consider sex- and age-specific vulnerabilities related to dural bleeding and how sensitization of the dural innervation by bleeding may influence these reflexes, potentially leading to collapse or even death after otherwise trivial insults.

When cases of suspected abusive head trauma are adjudicated in courts of law, several alternative theories of causation are frequently presented. This paper reviews common theories and examines their scientific basis.

It has been suggested that there is a causal relationship between hypoxia and subdural hemorrhage (SDH) in infancy. The purpose of this study was to review the incidence of SDH in infants with congenital heart disease and explore the relationship between SDH and hypoxia.

Review of data collected for a prospective longitudinal cohort study of infants undergoing surgery for congenital heart disease in New Zealand and Australia. Infants underwent serial MRI scans of the brain in the first 3 months of life. All oxygen saturation recordings and MRI results were extracted and infants assigned to categories by degree of hypoxia. The data were then examined for any statistically significant relationship between hypoxia and SDH.

One hundred fifty-two infants underwent MRI scans, and 66 (43%) had 145 loci of SDH. New SDH was seen in 12 infants after cardiac surgery. Of the loci of SDH, 63 (43%) were supratentorial, and most of these were interhemispheric, parietal, or temporal. SDH present on the first MRI persisted beyond 28 days of life in 8 infants. There was no demonstrable relationship between SDH and hypoxia.

Asymptomatic SDH is common in young infants with congenital heart disease, at a frequency similar to that of those without congenital heart disease. These SDHs may occur in locations where they occur in abusive head trauma, but they are typically small and resolve within 3 months of birth. We were unable to demonstrate any association between hypoxia and SDH in this cohort.

To determine whether the brain-body weight ratio is increased in sudden infant death syndrome (SIDS).

Review of autopsy files from Forensic Science SA, South Australia was undertaken over an eight-year period from 1999 to 2006, with classification of cases according to the San Diego definition. Sudden and/or unexpected deaths in previously healthy infants due to asphyxia or infection were selected as controls.

There were 42 SIDS cases and 25 controls. The SIDS cases were aged from 1 to 42 weeks (mean: 16.26 ± 1.5 weeks) with a male to female ratio of 26:16. The control infants were aged from 3 to 48 weeks (mean: 19.24 ± 2.9 weeks) (P > 0.05) (M:F = 16:9) and included 13 cases of asphyxia and 12 cases of sepsis. Comparison of the brain-body weight ratios failed to demonstrate a significant difference: SIDS mean = 0.121 ± 0.003; control mean = 0.115 ± 0.003 (P > 0.05).

Although, there was a trend towards higher brain-body weight ratios in SIDS infants, this did not reach significance. The role of brain weight in the aetiology of SIDS remains controversial.

The "Shaken Baby" syndrome (SBS) is the subject of intense controversy; the diagnosis has in the past depended on the triad of subdural haemorrhage (SDH), retinal haemorrhage and encephalopathy. While there is no doubt that infants do suffer abusive injury at the hands of their carers and that impact can cause catastrophic intracranial damage, research has repeatedly undermined the hypothesis that shaking per se can cause this triad. The term non-accidental head injury has therefore been widely adopted. This review will focus on the pathology and mechanisms of the three physiologically associated findings which constitute the "triad" and are seen in infants suffering from a wide range of non-traumatic as well as traumatic conditions. "Sub" dural bleeding in fact originates within the deep layers of the dura. The potential sources of SDH include: the bridging veins, small vessels within the dura itself, a granulating haemorrhagic membrane and ruptured intracranial aneurysm. Most neuropathologists do not routinely examine eyes, but the significance of this second arm of the triad in the diagnosis of Shaken Baby syndrome is such that it merits consideration in the context of this review. While retinal haemorrhage can be seen clinically, dural and subarachnoid optic nerve sheath haemorrhage is usually seen exclusively by the pathologist and only rarely described by the neuroradiologist. The term encephalopathy is used loosely in the context of SBS. It may encompass anything from vomiting, irritability, feeding difficulties or floppiness to seizures, apnoea and fulminant brain swelling. The spectrum of brain pathology associated with retinal and subdural bleeding from a variety of causes is described. The most important cerebral pathology is swelling and hypoxic-ischaemic injury. Mechanical shearing injury is rare and contusions, the hallmark of adult traumatic brain damage, are vanishingly rare in infants under 1 year of age. Clefts and haemorrhages in the immediate subcortical white matter have been assumed to be due to trauma but factors specific to this age group offer other explanations. Finally, examples of the most common causes of the triad encountered in clinical diagnostic and forensic practice are briefly annotated.

Because of the controversy involving the determination of child abuse, or nonaccidental injury (NAI), radiologists must be familiar with the issues, literature, and principles of evidence-based medicine to understand the role of imaging. Children with suspected NAI must receive protective evaluation along with a timely and complete clinical and imaging work-up. Imaging findings cannot stand alone and must be correlated with clinical findings, laboratory testing, and pathologic and forensic examinations. Only the child protection investigation may provide the basis for inflicted injury in the context of supportive clinical, imaging, biomechanical, or pathology findings.

The aim of this study was to determine the frequency of subdural haematomas (SDHs) occurring in infants presenting following atraumatic cardiorespiratory collapse. This study was a review of retrospective case notes, brain imaging and post-mortem examinations carried out in the paediatric intensive care unit (PICU) and emergency department (ED) in a tertiary paediatric centre in the UK. The study included infants and children less than 4 years old dying in the ED or admitted to the PICU after atraumatic cardiorespiratory arrest. We identified macroscopic SDHs on brain imaging or post-mortem examination. Of those children who experienced a cardiorespiratory arrest from a non-traumatic cause and met inclusion criteria, 33 presented and died in the ED and 17 were admitted to the PICU. These children had a post-mortem examination, brain imaging or both. None of these infants had a significant SDH. One child had a small clot adherent to the dura found on post-mortem and two had microscopic intradural haemorrhage, but it is unclear in each case whether this was artefact, as each had otherwise normal brains. Subdural haematoma arising in infants or young children in the context of catastrophic cardiorespiratory compromise from a non-traumatic cause was not observed.

The natural history of posttraumatic meningeal bleeding in infants is poorly documented, and the differences between inflicted head injury (IHI) and accidental trauma (AT) are debated. Autopsy findings have suggested that anoxia also plays a role in bleeding; however, these findings may not reflect what occurs in live trauma patients.

We studied the natural history of traumatic meningeal bleeding in infants using serial computed tomography (CT) scans in corroborated IHI and AT.

From our prospective series, we selected corroborated cases (confessed IHI or AT having occurred in public), who underwent at least three CT scans in the acute phase. We performed a semiquantitative analysis of meningeal bleeding using a four-tier scale (absent, faint, frank, and thick) derived from the Fisher grading for aneurysmal bleeding in four regions of interest (convexity, falx cerebri, sagittal sinus, and tentorium cerebelli).

We studied 20 cases: ten IHI and ten AT. Bleeding was maximal at the convexity initially, then increased along the falx and sagittal sinus, and then along the tentorium. Decrease and disappearance of blood was variable according to the site and the initial quantity of blood. We found no difference between IHI and AT.

Our findings suggest that the primary site of meningeal bleeding in infantile head trauma is the convexity of the brain; blood cells then migrate toward the midline following the flow of cerebrospinal fluid circulation and inferiorly following gravity. The pattern of bleeding in traumatic cases appears similar in IHI and AT but different from anoxic lesions.

Subdural bleeding (SDB) in infants is considered an essential symptom of nonaccidental head injury (NAHI). Recently, this view has been challenged by the "unified hypothesis," which claims that SDB in infants is related to hypoxia and brain swelling rather than to traumatic shearing of bridging veins. We analyzed a large series of infants' autopsies for the presence and causes of SDB, which should be a common event according to the unified hypothesis.

Autopsy, clinical, and legal information for infants <1 year of age from a single institution over 50 years were analyzed regarding cause of death, presence, morphology, and cause of SDB, and brain weight.

From a total of 16 661 autopsies during the study period, 715 (4.3%) involved infants <1 year of age. Fifty (7.0%) of those had SDB. NAHI was identified in 17 patients. The most common cause of SDB was trauma (15 cases [30.0%]), with NAHI accounting for 14 cases. SDB was present in 82.4% of patients with NAHI but only 5.2% of infants with other causes of death. Four patients (8.0%) had unexplained SDB with no discernible cause of bleeding. Statistical analysis did not reveal any correlation between the presence of SDB and brain weight.

In the study population, unexplained SDB in infants was an extreme rarity. Moreover, a correlation between brain swelling and the presence of SDB could not be drawn. Our data argue strongly against the unified hypothesis and strengthen the association between SDB and NAHI in infancy.

The occurrence of subdural hemorrhage (SDH) on the convexities of the cerebral hemispheres is not an unusual finding in the setting of intrauterine, perinatal, or neonatal deaths, the hemorrhage usually presenting either as a thin film over the occipital poles or as a small infratentorial bleed. Working in 2 referral centers with over 30,000 deliveries per year, we routinely examine the dura macroscopically and histologically in nonmacerated fetuses over 24 weeks in gestation and in neonates. This paper describes our experience of intradural hemorrhage (IDH) and SDH associated with hypoxia. Our series comprises 25 fetuses and 30 neonates with obvious macroscopic intradural hemorrhage and hypoxia of varying degrees of severity diagnosed by systematic examination of the brain. Fetal gestational age ranged from 26-41/40 weeks (all no more than 24 hours from intrauterine death), while the 30 neonates lived for between 1 hour and 19 days. Simultaneously with IDH, frank SDH was seen in 2 of 3 of all cases (16 fetuses and 20 neonates). Intradural hemorrhage was more prominent in the posterior falx and tentorium, most likely because of the existence of 2 venous plexus at these sites. Our findings demonstrate that SDH and cerebral hypoxia are common associations of IDH and that SDH (often seen as a thin film ofhemorrhage) almost always occurs in association with diffuse falcine IDH. Diffuse IDH with SDH are more frequently associated with severe or moderate hypoxic ischemic encephalopathy (HIE), while mild or early HIE is more common with focal IDH without SDH.

Subdural haemorrhage (SDH) in the infant has a different pattern from that seen in the older child and adult. It is usually a widespread, bilateral, thin film, unlike the thick, space-occupying and often unilateral clot seen in older children and adults after trauma. Whether both arise by the same mechanism is unknown, but it seems unlikely. Most SDH is said to be due to trauma but in infants there are other, atraumatic causes. Birth is also important; recent MRI studies show an incidence of almost 50% in asymptomatic neonates. Traumatic SDH is said to result from rupture of bridging veins but new insights into the anatomy of infant dura suggest a dural origin for thin film subdural bleeding in young babies. Acute SDH usually rapidly resolves, but sometimes develops into a chronic fluid collection. Healing of SDH is by formation of a granulating membrane which may confer vulnerability to rebleeding, either spontaneously or after an otherwise innocuous event. SDH has a particular significance as one of the features of the triad (together with retinal haemorrhage and encephalopathy) associated with non-accidental injury. As the possibility of non-accidental injury is often first raised by a radiologic report of subdural bleeding, it becomes critically important in the interpretation of the scan appearances to understand the unique physiology and anatomy of the infant dura.