Significance of a subdural hematoma in a child with external hydrocephalus

Benign enlargement of the subarachnoid spaces and subdural collections-when to evaluate for abuse

In infants without a history of trauma, subdural haemorrhages should raise the concern for an abusive head injury, particularly when they are associated with bridging vein clotting/rupture or with septations. However, non-haemorrhagic, fluid-appearing subdural collections (also called hygromas) may also be the result of abuse. Subdural collections have also been uncommonly observed in patients with benign enlargement of the subarachnoid spaces (BESS) and a few large-scale studies accurately investigate the incidence and the significance. Currently, there is a wide variation of practices in children with BESS and subdural collections. Due to the social risks associated with abuse evaluation and the perceived risk of radiation exposure, there might be a reluctance to fully evaluate these children in some centres. The diagnosis of physical abuse cannot be substantiated nor safely excluded in infants with BESS and subdural collection(s), without investigation for concomitant traumatic findings. The exact prevalence of occult injuries and abuse in these infants is unknown. In macrocephalic infants with subdural collections and imaging features of BESS, thorough investigations for abuse are warranted and paediatricians should consider performing full skeletal surveys even when fundoscopy, social work consult, and detailed clinical evaluation are unremarkable.

Re-evaluation of medical findings in alleged shaken baby syndrome and abusive head trauma in Norwegian courts fails to support abuse diagnoses

AIM

The criteria for diagnosing abusive head trauma (AHT) are not well defined and this condition might be diagnosed on failing premises. Our aim was to review criminal AHT cases in Norwegian courts by scrutinising the underlying medical documentation.

METHODS

Cases were identified in the data registry for Norwegian courts from 2004 to 2015. Documentation was obtained from relevant health institutions. The medical co-authors first made independent evaluations of the documentation for each child, followed by a consensus evaluation.

RESULTS

A total of 17 children (11 boys) were identified, all diagnosed as AHT by court appointed experts, 15 were infants (mean age 2.6 months). A high proportion (41.2%) was born to immigrant parents and 31.3% were premature. The medical findings could be explained by alternative diagnoses in 16 of the 17 children; 8 boys (7 infants - mean age 2.9 months) had clinical and radiological characteristics compatible with external hydrocephalus complicated by chronic subdural haematoma. Six children (five infants with mean age 2.1 months) had a female preponderance and findings compatible with hypoxic ischaemic insults.

CONCLUSION

The medical condition in most children had not necessarily been caused by shaking or direct impact, as was originally concluded by the court experts.

Chronic subdural hemorrhage predisposes to development of cerebral venous thrombosis and associated retinal hemorrhages and subdural rebleeds in infants

For infants presenting with subdural hemorrhage, retinal hemorrhage, and neurological decline the "consensus" opinion is that this constellation represents child abuse and that cerebral venous sinus thrombosis and cortical vein thrombosis is a false mimic. This article contends that this conclusion is false for a subset of infants with no evidence of spinal, external head, or body injury and is the result of a poor radiologic evidence base and misinterpreted data. Underdiagnosis of thrombosis is the result of rapid clot dissolution and radiologic under recognition. A pre-existing/chronic subdural hemorrhage predisposes to development of venous sinus thrombosis/cortical vein thrombosis, triggered by minor trauma or an acute life-threatening event such as dysphagic choking, variably leading to retinal and subdural hemorrhages and neurologic decline. These conclusions are based on analysis of the neuroradiologic imaging findings in 11 infants, all featuring undiagnosed cortical vein or venous sinus thrombosis. Subtle neuroradiologic signs of and the mechanisms of thrombosis are discussed. Subarachnoid hemorrhage from leaking thrombosed cortical veins may be confused with acute subdural hemorrhage and probably contributes to the development of retinal hemorrhage ala Terson's syndrome. Chronic subdural hemorrhage rebleeding from minor trauma likely occurs more readily than bleeding from traumatic bridging vein rupture. Radiologists must meet the challenge of stringent evaluation of neuro imaging studies; any infant with a pre-existing subdural hemorrhage presenting with neurologic decline must be assumed to have venous sinus or cortical vein thrombosis until proven otherwise.

Examining perinatal subdural haematoma as an aetiology of extra-axial hygroma and chronic subdural haematoma

AIM

Benign external hydrocephalus (BEH), hygroma and chronic subdural haematoma are extra-axial fluid collections in infants. MRI studies have shown that almost half of all new-borns have perinatal subdural blood, generally referred to as subdural haematoma (SDH) or perinatal SDH. Epidemiologically there are striking similarities between chronic SDH and BEH in infants.

METHODS

Discussion of pathophysiological mechanisms for BEH and chronic SDH, based on existing literature.

RESULTS

Perinatal SDH is common, and we hypothesise that this condition in some infants develop into extra-axial fluid collections, known as hygroma, BEH or chronic subdural haematoma. The mechanism seems to be an intradural bleeding that creates an obstructive layer preventing normal CSF absorption. The site where the bleeding originates from and those areas enveloped in blood from the primary damaged area are prone to later rebleeds, seen as 'acute on chronic' haematomas. With steady production of CSF and the blockage, increased intracranial pressure drives the accelerated skull growth seen in many of these children.

CONCLUSION

Perinatal SDH hampers CSF absorption, possibly leading to BEH and chronic SDH, with a high risk of false accusations of abuse. Close monitoring of head circumference could prove vital in detecting children with this condition.

Macrocephaly: Solving the Diagnostic Dilemma

Macrocephaly is a relatively common clinical condition affecting up to 5% of the pediatric population. It is defined as an abnormally large head with an occipitofrontal circumference greater than 2 standard deviations above the mean for a given age and sex. Megalencephaly refers exclusively to brain overgrowth exceeding twice the standard deviation. Macrocephaly can be isolated and benign or may be the first indication of an underlying congenital, genetic, or acquired disorder, whereas megalencephaly is more often syndromic. Megalencephaly can be divided into 2 subtypes: metabolic and developmental, caused by genetic defects in cellular metabolism and alterations in signaling pathways, respectively. Neuroimaging plays an important role in the evaluation of macrocephaly, especially in the metabolic subtype which may not be overtly apparent clinically. This article outlines the diverse etiologies of macrocephaly, delineates their clinical and radiographic features, and suggests a clinicoradiological algorithm for evaluation.

Evaluation of the Hypothesis That Choking/ALTE May Mimic Abusive Head Trauma

OBJECTIVE

Apparent life-threatening events (ALTEs), often accompanied by choking, have been hypothesized to cause subdural hemorrhages (SDH), retinal hemorrhages, and brain injury. If the choking/ALTE hypothesis were true, children who present with ALTE and SDH would have fewer extracranial injuries suspicious for abuse than those with SDH and no ALTE. We aimed to compare the prevalence of suspicious extracranial injuries in children who have ALTE-associated SDH to those with non-ALTE SDH.

METHODS

We performed a 5-year retrospective case-control study of children <2 years of age with SDH evaluated by the Child Abuse Pediatrics program at a children's hospital. Subjects were classified as ALTE-associated SDH and non-ALTE SDH on the basis of ALTE definitions as proposed by the authors of the choking/ALTE hypothesis. The 2 groups were compared for the prevalence of suspicious extracranial injuries.

RESULTS

Of 170 study subjects, 64 had an ALTE-associated SDH and 106 had non-ALTE SDH. ALTE-associated SDH subjects were nearly 5 times more likely to have at least one suspicious extracranial injury (odds ratio [OR] 4.8, 95% confidence interval [CI] 1.9-12.1) and were more likely to have individual types of suspicious extracranial injuries, including retinoschisis (OR 4.1, 95% CI 1.6-10.2), high-specificity bruising (OR 2.6, 95% CI 1.3-4.9), and internal abdominal injury (3.5, 95% CI 1.2-9.9). Subjects with ALTE-associated SDH were also significantly more likely to die or have persistent neurologic impairment. All 10 subjects with a dysphagic-choking type ALTE had at least 1 suspicious extracranial injury.

CONCLUSIONS

ALTEs are not supported as causative mechanisms for findings concerning abusive head trauma.

Investigating the possibility and probability of perinatal subdural hematoma progressing to chronic subdural hematoma, with and without complications, in neonates, and its potential relationship to the misdiagnosis of abusive head trauma

The high incidence of subdural hematoma (SDH) from birthing was first identified with MRI by Looney in 2007 and was then more accurately determined by Rooks in 2008. Rooks screened 101 "normal" deliveries and demonstrated that 46% of the babies in her series and by inference, approximately 46% of the 4 million born normally in the US have SDH that formed in the perinatal (birthing) period during labor. Both metabolic strain and physical forces exerted on the head damage the capillaries within the dura (the intradural capillary bed), which is the source of the blood in the SDH that results from labor and delivery or at times from labor alone. While child abuse pediatricians relying on Rooks, maintain that no permanent complications result, her study was limited to 101 subjects and the sole criteria for resolution was the resolution of the SDH as seen on follow-up MRI. In fact, Rooks did have one patient (1%) who had complications that lead to symptoms and findings often associated with abuse. The purpose of this article is to explore if there is a complication rate for perinatal (PSDH) that supports that 1% of complications that are definable by different criteria. Next, if there are complications, how many of the roughly 2,000,000 cases of perinatal acute subdural hematoma every year in the United States will suffer them? Then, what are the clinical manifestations of the complications if they occur? Lastly, do the complications cause or mimic some or all of the findings that are offered by board certified child abuse pediatricians as evidence of child abuse? The article argues that a small percentage, but significant number of neonates, suffer birth related complications and findings secondary to the development of chronic subdural hematoma CSDH) that are often misdiagnosed as abusive head trauma.

The "Shaken Baby" syndrome: pathology and mechanisms

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.

Benign external hydrocephalus: a review, with emphasis on management

Benign external hydrocephalus in infants, characterized by macrocephaly and typical neuroimaging findings, is considered as a self-limiting condition and is therefore rarely treated. This review concerns all aspects of this condition: etiology, neuroimaging, symptoms and clinical findings, treatment, and outcome, with emphasis on management. The review is based on a systematic search in the Pubmed and Web of Science databases. The search covered various forms of hydrocephalus, extracerebral fluid, and macrocephaly. Studies reporting small children with idiopathic external hydrocephalus were included, mostly focusing on the studies reporting a long-term outcome. A total of 147 studies are included, the majority however with a limited methodological quality. Several theories regarding pathophysiology and various symptoms, signs, and clinical findings underscore the heterogeneity of the condition. Neuroimaging is important in the differentiation between external hydrocephalus and similar conditions. A transient delay of psychomotor development is commonly seen during childhood. A long-term outcome is scarcely reported, and the results are varying. Although most children with external hydrocephalus seem to do well both initially and in the long term, a substantial number of patients show temporary or permanent psychomotor delay. To verify that this truly is a benign condition, we suggest that future research on external hydrocephalus should focus on the long-term effects of surgical treatment as opposed to conservative management.

Imaging of nonaccidental injury and the mimics: issues and controversies in the era of evidence-based medicine

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.

Subdural hematoma in infants: can it occur spontaneously? Data from a prospective series and critical review of the literature

BACKGROUND

Subdural hematomas (SDH) in infants often result from nonaccidental head injury (NAHI), which is diagnosed based on the absence of history of trauma and the presence of associated lesions. When these are lacking, the possibility of spontaneous SDH in infant (SSDHI) is raised, but this entity is hotly debated; in particular, the lack of positive diagnostic criteria has hampered its recognition. The role of arachnoidomegaly, idiopathic macrocephaly, and dehydration in the pathogenesis of SSDHI is also much discussed.

PURPOSE

We decided to analyze apparent cases of SSDHI from our prospective databank.

MATERIALS AND METHODS

We selected cases of SDH in infants without systemic disease, history of trauma, and suspicion of NAHI. All cases had fundoscopy and were evaluated for possible NAHI. Head growth curves were reconstructed in order to differentiate idiopathic from symptomatic macrocrania.

RESULTS

Sixteen patients, 14 males and two females, were diagnosed with SSDHI. Twelve patients had idiopathic macrocrania, seven of these being previously diagnosed with arachnoidomegaly on imaging. Five had risk factors for dehydration, including two with severe enteritis. Two patients had mild or moderate retinal hemorrhage, considered not indicative of NAHI. Thirteen patients underwent cerebrospinal fluid drainage. The outcome was favorable in almost all cases; one child has sequels, which were attributable to obstetrical difficulties.

CONCLUSION

SSDHI exists but is rare and cannot be diagnosed unless NAHI has been questioned thoroughly. The absence of traumatic features is not sufficient, and positive elements like macrocrania, arachnoidomegaly, or severe dehydration are necessary for the diagnosis of SSDHI.

Neuroimaging of abusive head trauma

The diagnostic process for evaluating suspected abusive head trauma in infants and children has evolved with technological advances in neuroimaging. Since Caffey first described a series of children with chronic subdural hematomas and multiple long bone fractures, radiologists have played an important role, along with pediatricians and pathologists, in evaluating abused children. Neuroimaging modalities include ultrasound, CT scans, and MRI technology. Each has distinct clinical applications, as well as practical uses in the clinical diagnostic process of AHT. Importantly, neuroimaging assists in the process of differential diagnosis of other conditions which may mimic AHT. Collaboration between neuroradiologists, clinicians, and pathologists remains critical to making the appropriate diagnosis. Careful history, physical examination, and investigation by legal authorities form the components that result in accurate assessment of any case. This paper reviews pertinent neuroimaging modalities currently utilized in the diagnosis of AHT, describing clinical indications and a collaborative approach to this process.

The neuropathology of infant subdural haemorrhage

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.

Benign extracerebral fluid collections in infancy: clinical presentation and long-term follow-up

OBJECT

Benign extracerebral fluid collections are common in infants, but there are unanswered questions regarding presentation and long-term outcome. This study was undertaken to establish head size at birth, head size at presentation, head growth over time, history of presentation, indications for surgery, and long-term results.

METHODS

Cases of benign extracerebral fluid collections in infancy were retrospectively reviewed. Data pertaining to clinical presentation, progress, and long-term follow-up were evaluated. Patients were divided into two groups on the basis of the presence or absence of increased signal intensity of fluid in the extracerebral space on T1-weighted magnetic resonance images. Group 1 consisted of 39 patients who had benign extracerebral fluid collections without any subdural collections. Group 2 consisted of nine patients who had a chronic subdural hematoma or hygroma without a history of trauma and had generous subarachnoid spaces and/or a history of premature birth. Patients were observed for an average of 49 months.

RESULTS

Group 1 included 39 patients (ages at presentation 3-12 months); the most common presentation in this group was macrocephaly (28 cases). Of those Group 1 cases in which data regarding gestational age at birth were available, 15 births were either severely or mildly premature and 14 were full term. Of those Group 1 patients with adequate data, 14 had an occipitofrontal circumference (OFC) in the 50th to 98th percentile at birth and two had OFCs greater than the 98th percentile. Measurements obtained at 24 months of age were available for 18 Group 1 patients: OFC was at approximately the 98th percentile in eight (all eight born at full term) and more than 1 cm larger than the 98th percentile in 10. Head growth in Group 1 patients continued to decrease, approaching the 98th percentile after 24 months of age. Only three of the 39 patients in Group 1 required shunt placement. Of the 33 Group 1 patients for whom long-term follow-up was available, 30 were developing normally, and three had mild developmental delays. Group 2 included nine patients (ages at presentation 3-7 months); the most common presentations were large head (three patients) and seizures (three patients). Data concerning gestational age at birth were available in eight Group 2 cases: birth was severely premature in four and gestation was full term in four. Five Group 2 patients were treated surgically-two with subduroperitoneal (SDP) shunt placement, two with subdural punctures, and one with subdural punctures and SDP shunt placement. Adequate follow-up information was available in eight of nine Group 2 cases; all eight patients were found to be developing normally.

CONCLUSIONS

Group 1 patients usually had a normal head size at birth, they rarely required shunt placement, their head growth eventually leveled off toward the 98th percentile line, and their outcomes were generally good. Although five of nine Group 2 patients required subdural punctures and/or SDP shunt placement, that group of patients also developed well. Infants with nontraumatic subdural hematomas or hygromas, presumably associated with benign extracerebral fluid collections, can often experience significant resolutions of the hematoma or hygroma within several months without surgical treatment.

Neuroimaging of nonaccidental head trauma: pitfalls and controversies

Although certain neuroimaging appearances are highly suggestive of abuse, radiological findings are often nonspecific. The objective of this review is to discuss pitfalls, controversies, and mimics occurring in neuroimaging of nonaccidental head trauma in order to allow the reader to establish an increased level of comfort in distinguishing between nonaccidental and accidental head trauma. Specific topics discussed include risk factors, general biomechanics and imaging strategies in nonaccidental head trauma, followed by the characteristics of skull fractures, normal prominent tentorium and falx versus subdural hematoma, birth trauma versus nonaccidental head trauma, hyperacute versus acute on chronic subdural hematomas, expanded subarachnoid space versus subdural hemorrhage, controversy regarding subdural hematomas associated with benign enlarged subarachnoid spaces, controversy regarding hypoxia as a cause of subdural hematoma and/or retinal hemorrhages without trauma, controversy regarding the significance of retinal hemorrhages related to nonaccidental head trauma, controversy regarding the significance of subdural hematomas in general, and pitfalls of glutaric aciduria type 1 and hemophagocytic lymphohistiocytosis mimicking nonaccidental head trauma.

Prevalence and evolution of intracranial hemorrhage in asymptomatic term infants

BACKGROUND AND PURPOSE

Subdural hemorrhage (SDH) is often associated with infants experiencing nonaccidental injury (NAI). A study of the appearance and natural evolution of these birth-related hemorrhages, particularly SDH, is important in the forensic evaluation of NAI. The purpose of this study was to determine the normal incidence, size, distribution, and natural history of SDH in asymptomatic term neonates as detected by sonography (US) and MR imaging within 72 hours of birth.

MATERIALS AND METHODS

Birth history, delivery method, duration of each stage of labor, pharmaceutic augmentation, and complications during delivery as well as postnatal physical examination were recorded. Brain MR imaging and US were performed on 101 asymptomatic term infants at 3-7 days, 2 weeks, 1 month, and 3 months. Clinical follow-up at 24 months was recorded.

RESULTS

Forty-six neonates had SDH by MR imaging within 72 hours of delivery. SDH was seen in both vaginal and cesarean deliveries. All neonates were asymptomatic, with normal findings on physical examination. All 46 had supratentorial SDH seen in the posterior cranium. Twenty (43%) also had infratentorial SDH. US detected 11 of the 20 (55%) infratentorial SDHs and no supratentorial SDH. Most SDHs present at birth were <or=3 mm and had resolved by 1 month, and all resolved by 3 months on MR imaging. Most children with SDHs had normal findings on developmental examinations at 24 months.

CONCLUSION

SDH in asymptomatic term neonates after delivery is limited in size and location.

Imaging of the central nervous system in suspected or alleged nonaccidental injury, including the mimics

Because of the widely acknowledged controversy in nonaccidental injury, the radiologist involved in such cases must be thoroughly familiar with the imaging, clinical, surgical, pathological, biomechanical, and forensic literature from all perspectives and with the principles of evidence-based medicine. Children with suspected nonaccidental injury versus accidental injury must not only receive protective evaluation but also require a timely and complete clinical and imaging workup to evaluate pattern of injury and timing issues and to consider the mimics of abuse. All imaging findings must be correlated with clinical findings (including current and past medical record) and with laboratory and pathological findings (eg, surgical, autopsy). The medical and imaging evidence, particularly when there is only central nervous system injury, cannot reliably diagnose intentional injury. Only the child protection investigation may provide the basis for inflicted injury in the context of supportive medical, imaging, biomechanical, or pathological findings.

Inflicted traumatic brain injury: advances in evaluation and collaborative diagnosis

The determination that a traumatic brain injury is not accidental requires data collection from multiple domains: historical, clinical, laboratory, radiographic, environmental and psychosocial. These essential, yet disparate, types of information must be synthesized in a collaborative and interdisciplinary process to formulate a medical opinion with regard to the cause of an injury, and the final opinion has tremendous consequences for children and families. Medically directed child protection teams have emerged as the standard of care in many children's hospitals and child abuse pediatrics is now a recognized medical subspecialty with board certification available in the next several years. Not only do the child and family benefit from this coordinated effort, but there are also great benefits for the members of the child protection team: more clearly defined responsibilities, redirected focus on treatment for the surgeon, and increased confidence that the opinion is based upon consensus and current scientific knowledge. By this process and its division of labor, the child abuse pediatrician assumes responsibility for ensuring that a final medical opinion is arrived at, and then advocates for appropriate disposition for the child. The child abuse pediatrician is responsible for establishing institutional standards for family evaluation, collecting all necessary medical data and directing a consensus-based decision making process that is based upon current medical knowledge, medical literature and experience. The child abuse pediatrician also assumes the role of primary communication conduit for investigational agencies and the courts. The neurosurgeon is a key member of the child protection team and relies on the team to obtain necessary historical information to address consistency of the mechanism with the sustained injuries and has an integral role in determining the team's final opinion. An interdisciplinary response to inflicted traumatic brain injury is the cornerstone for establishing a rigorous standard of care; it also fosters education across medical subspecialties where controversy has been a significant part of the landscape. Valid and useful clinical research that describes head injury as accidental or inflicted can only be performed in the context of an interdisciplinary, medically directed child protection team that strives for objectivity and precision in the determination of the manner of an injury.

A witnessed short fall mimicking presumed shaken baby syndrome (inflicted childhood neurotrauma)

A witnessed fall backwards of an infant from a sitting position resulted in the subdural hematoma and retinal hemorrhages characteristic of presumed shaken baby syndrome. Violent shaking is not necessary to produce these findings.