Imaging of spinal injury in abusive head trauma: a retrospective study

Background

Spinal imaging has been a neglected part of abusive head trauma (AHT) imaging. As most of the radiographs and CT spine are negative in AHT in infants, the cervical spine is assumed to be normal. There is increasing evidence in the role of injury to brainstem and cervical cord in the pathogenesis of AHT. In addition, in courts of law, there is fierce debate about AHT, its mimics and other disparate nontraumatic diagnoses explaining the neuroradiological and skeletal findings. However, this discussion ignores the evidence and significance of spinal injury. We sought to study the cervical spine in an AHT cohort to understand the true prevalence of spinal injuries in AHT and contrast it with cohorts of accidental and nontraumatic groups to give the clinicians a robust diagnostic tool in evaluating AHT.

Objective

The purpose of this study is to compare the relative incidence of spinal ligamentous and soft-tissue abnormalities on spinal MRI among three groups of children ages <48 months: 1) those with AHT, 2) those with accidental trauma, and 3) those with nontraumatic conditions.

Materials and methods

This comparative study included 183 children who underwent spine MRI: 67 with AHT, 46 with accidental trauma and a clinical suspicion of spinal injury, and 70 with nontraumatic conditions. Clinical and radiographic findings were collected in all cases and were analyzed retrospectively to identify MRI evidence of traumatic spinal injuries. The incidence of spinal injuries among the three groups was compared. The incidence of spinal ligamentous injuries was calculated for those with and without radiographic evidence of hypoxic-ischemic encephalopathy. All comparisons were performed using Fisher exact test with P?Results Cervical spine ligamentous injuries (predominantly the nuchal, atlanto-occipital and atlanto-axial ligaments) were present in 78% of the AHT group, 46% of the accidental trauma group and 1% of the nontraumatic group; all of these differences were statistically significant. Among the AHT group, ligamentous injuries were statistically correlated with evidence of brain ischemia.

Conclusion

Injury to the cervical spinal posterior ligamentous complex is common in AHT and even more prevalent than in clinically symptomatic traumatic cases. The high correlation between the radiographic findings of occipitocervical ligamentous injuries and hypoxic-ischemic brain injury is consistent with an interpretation that transient upper occipitocervical spinal cord injury in AHT leads to disordered breathing and results in hypoxic-ischemic encephalopathy. We recommend imaging the entire spine in AHT to properly identify and classify these injuries.     

Usefulness of MRI detection of cervical spine and brain injuries in the evaluation of abusive head trauma

Background

In the evaluation of children younger than 3 years with intracranial hemorrhage it can be difficult to determine whether the cause of hemorrhage was traumatic, and if so, whether abusive head trauma (AHT) is a possibility. Cervical spine MRI is not a routine part of the nationally recommended imaging workup for children with suspected abusive head trauma. There is increasing evidence that spinal injuries are found at autopsy or MRI in abused children. However the prevalence of cervical spine injuries in children evaluated for abusive head trauma is unknown. We sought to determine both the incidence and the spectrum of cervical spine and brain injuries in children being evaluated for possible abusive head trauma. We also examined the relationship between cervical and brain MRI findings and selected study outcome categories.

Materials and methods

This study is a 3-year retrospective review of children evaluated for abusive head trauma. Inclusion criteria were: children with head trauma seen at our institution between 2008 and 2010, age younger than 36 months, availability of diagnostic-quality brain and cervical spine MRI, and child abuse team involvement because abusive head trauma was a possibility. A child abuse pediatrician and pediatric radiologists, all with board certification, were involved in data collection, image interpretation and data analysis. Statistical analysis was performed using Stata v12.1.

Results

The study included 74 children (43 boys, 31 girls) with a mean age of 164 days (range, 20–679 days). Study outcomes were categorized as: n?=?26 children with accidental head trauma, n?=?38 with abusive head trauma (n?=?18 presumptive AHT, n?=?20 suspicious for AHT), and n?=?10 with undefined head trauma. We found cervical spine injuries in 27/74 (36%) children. Most cervical spine injuries were ligamentous injuries. One child had intrathecal spinal blood and two had spinal cord edema; all three of these children had ligamentous injury. MRI signs of cervical injury did not show a statistically significant relationship with a study outcome of abusive head trauma or help discriminate between accidental and abusive head trauma. Of the 30 children with supratentorial brain injury, 16 (53%) had a bilateral hypoxic–ischemic pattern. There was a statistically significant relationship between bilateral hypoxic–ischemic brain injury pattern and abusive head trauma (P?<?0.05). In addition, the majority (81%) of children with bilateral hypoxic–ischemic brain injuries had cervical injuries.

Conclusion

Although detection of cervical spine injuries by MRI does not discriminate between accidental and abusive head trauma, it can help to distinguish a traumatic from non-traumatic intracranial subdural hemorrhage. Cervical MRI should be considered in children with acute intracranial bleeds and otherwise non-contributory history, physical examination and ophthalmological findings. There is a statistically significant relationship between diffuse hypoxic–ischemic brain injury patterns and abusive head trauma. The high incidence of cervical injuries in children with hypoxic–ischemic injuries suggests a causal relationship. Overall, increased utilization of brain and spine MRI in children being evaluated for abusive head trauma can be helpful.     

弥散加权成像在新生儿重度缺氧缺血性脑病早期评价中的意义

目的探索新生儿重度缺氧缺血性脑病（HIE）早期弥散加权成像（DWI）动态演变规律及其意义。方法对2006年1月至2007年2月收住我院14例重度HIE患儿,分别于生后72h。7、14、21d及8个月行DWI及常规MRI扫描。结果72h内,常规MRI的T1加权（T1WI）和T2加权（T2WI）均未见异常,DWI表现为双侧腹外侧丘脑对称性的高信号;7d常规MRI表现双侧腹外侧丘脑对称性T1WI高信号,T2WI稍低信号,DWI表现为双侧基底节高信号,而初期腹外侧丘脑高信号消失;14d常规MRI双侧丘脑、基底节对称性T1WI高信号,T2WI低信号;21d常规MRI双侧丘脑及基底节T1WI高信号,T2WI高信号,DWI则未见明显异常;8个月常规MRI脑沟变深、脑室扩大及脑外间隙增宽,基底节T2WI不规则的高信号。结论重度HIE（主要因急性的完全性窒息所致）生后初期DWI显示相同的病变部位（腹外侧丘脑和基底节）和相似的病变程度,但其异常信号很快消失,而常规MRI可继之弥补DWI的不足。     

Ischemic stroke following mild head injury is it the cause

Recognition of childhood stroke is difficult. Newer diagnostic modalities like magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) have made this task much easier. Head trauma usually causes hemorrhage. We are presenting seven cases of mild head injury presenting as ischamic stroke. Neuroimaging suggested infarct involving left basal ganglia and internal capsule in five and bilateral involvement in two cases. MRA done in three was normal.     

Cerebellar lesions in pediatric abusive head trauma

Pediatric abusive head trauma (AHT) or non accidental head trauma (NAHT) is a major cause of death from trauma in children under 2 years of age. Main etiological factor for non accidental head trauma is shaking a baby, causing brain injury by rotational head acceleration and deceleration. The consequent brain damage as shown by magnetic resonance imaging (MRI) is subdural haemorrhage and to a lesser extent parenchymal injuries of variable severity. Involvement of the cerebellum has very rarely been described.We report the clinical history and the development of cerebral magnetic resonance imaging findings in two children with serious brain injury following probable shaking who presented the typical “triad” with subdural haematoma, retinal haemorrhage and encephalopathy. We want to draw attention to cerebellar involvement characterized by cortico-subcortical signal alterations most prominent on T2w images following diffusion changes during the acute period. We discuss cerebellar involvement as a sign of higher severity of AHT which is probably underrecognized.     

新生儿缺氧缺血性脑病磁共振诊断与损伤类型的分类建议

新生儿缺氧缺血性脑病(HIE)有比较统一的临床诊断与分度标准,但是符合相同诊断标准的窒息所致HIE的临床表现、神经病理损伤类型有很大差异。磁共振成像(MRI)能很好地呈现HIE损伤类型、损伤进程,且与其远期神经发育结局密切相关,但不同MRI检查序列所反映的损伤表现可能不尽相同。弥散加权序列适宜的检查时间为出生后2~4 d,常规序列为出生后的4~8 d。HIE的MRI主要损伤类型有丘脑基底节+内囊后肢损伤、分水岭样损伤累及皮层和皮层下白质、局灶-多灶性微小性白质损伤,以及广泛全脑性损伤。严重的急性产时窒息易导致深部灰质损伤(丘脑基底节),也可累及脑干,锥体束是最易受累的白质纤维束,而反复间断性缺氧缺血以及伴有感染、低血糖等易导致分水岭区和深部白质损伤。但上述损伤类型有时很难明确区分,而是以某一类型为主,并非所有HIE都有特征性的MRI表现。     

Educational paper

Abusive head trauma (AHT) is a relatively common cause of neurotrauma in young children. Radiology plays an important role in establishing a diagnosis and assessing a prognosis. Computed tomography (CT), followed by magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI), is the best tool for neuroimaging. There is no evidence-based approach for the follow-up of AHT; both repeat CT and MRI are currently used but literature is not conclusive. A full skeletal survey according to international guidelines should always be performed to obtain information on possible underlying bone diseases or injuries suspicious for child abuse. Cranial ultrasonography is not indicated as a diagnostic modality for the evaluation of AHT. If there is a suspicion of AHT, this should be communicated with the clinicians immediately in order to arrange protective measures as long as AHT is part of the differential diagnosis. Conclusion: The final diagnosis of AHT can never be based on radiological findings only; this should always be made in a multidisciplinary team assessment where all clinical and psychosocial information is combined and judged by a group of experts in the field.     

Head injury pattern in children can help differentiate accidental from non-accidental trauma

Objectives

Our aim was to define the radiographic findings that help differentiate abusive head trauma (AHT) from accidental head injury.

Methods

Our trauma registry was queried for all children ≤5 years of age presenting with traumatic brain injury (TBI) from 1996–2011.

Results

Of 2,015 children with TBI, 71 % had accidental injury and 29 % had AHT. Children with AHT were more severely injured (ISS 22.1 vs 14.4; p < 0.0001) and had a higher mortality rate (15 vs 5 %; p < 0.0001). Patients with AHT had higher rates of diffuse axonal injury (14 vs 8 %; p < 0.0001) and subdural hemorrhage (76 vs 23 %; p < 0.0001). Children with accidental injury had higher rates of skull fractures (52 vs 21 %; p < 0.0001) and epidural hemorrhages (11 vs 3 %).

Conclusions

AHT occurred in 29 % of children and resulted in increased mortality rates. These children had higher rates of subdural hemorrhages and diffuse axonal injury. Physicians initially evaluating injured children must maintain a high index of suspicion for abuse in those who present with subdural hematoma or diffuse axonal injury.     

新生猪缺氧缺血性脑病早期弥散加权像变化及热休克蛋白70表达

目的探讨早期缺氧缺血性脑病(HIE)动物模型弥散加权像(DWI)变化和热休克蛋白(HSP)70表达的演变规律。方法3日龄新生猪19只随机分为正常对照组、假手术组、缺氧缺血组。用1.5T磁共振仪行DWI和T2WI检查;用表观弥散系数(ADC)图,测量病灶中心区和周边区ADC值;应用SP法计数中心区和周边区HSP70阳性细胞。结果缺氧缺血组出现四肢抽搐、角弓反张等体征。缺氧缺血后3 h DWI有高信号,ADC图有低信号。各组中心区与周边区ADC比较有显著差异(P<0.01)。缺氧缺血后3 h出现HSP70阳性细胞,6 h达高峰,之后逐渐下降,各组中心区和周边区HSP70阳性细胞计数比较有极显著差异(P<0.01)。结论DWI结合ADC值可以敏感而准确地显示HIE病灶;HSP70表达提示早期HIE病灶周边区有可逆的脑组织区域。     

MRI鉴别新生儿缺氧缺血性脑病与急性胆红素脑病的价值

目的：新生儿缺氧缺血性脑病(HIE) 与急性胆红素脑病的脑损害部位、早期临床症状存在相似性,应用影像学方法鉴别两类疾病有一定的临床意义。该文探讨常规磁共振成像（MRI）和扩散加权成像（DWI）鉴别新生儿HIE与急性胆红素脑病的价值。方法：回顾性分析该院2006年11月至2008年6月收治住院的15例伴有基底节累及的HIE新生儿和18例急性胆红素脑病新生儿的常规MRI表现;并进一步分析其中11例HIE及10例急性胆红素脑病患儿的DWI特点。结果：5例HIE患儿T1WI出现苍白球高信号,16例急性胆红素脑病患儿表现为苍白球高信号,HIE患儿苍白球高信号的出现率低于急性胆红素脑病（P<0.01）。9例HIE患儿出现壳核高信号,急性胆红素脑病患儿壳核均无高信号。急性胆红素脑病患儿底丘脑高信号的出现率高于HIE患儿（55.6% vs 13.3%, P<0.05）。HIE组和急性胆红素脑病组分别有8例和2例患儿还出现了脑内其他部位的异常信号（P<0.05）。7例HIE患儿DWI上,基底节出现高信号,而急性胆红素脑病患儿均无基底节异常信号。结论： 常规MRI及DWI有助于鉴别新生儿HIE和急性胆红素脑病。［中国当代儿科杂志,2009,11（3）：181-184］     

ICD-10-CM Codes for the Identification of Abusive Head Trauma in Administrative Datasets

ObjectiveWe sought to develop and validate a list of ICD-10-CM codes identifying abusive head trauma (AHT).MethodsSubjects included all children under 2 years with head trauma seen in the emergency department or admitted to one of 5 medical centers. Cases were classified as AHT, accidental head injury, or indeterminate based on chart review of the medical record. ICD-10-CM code list to identify cases of AHT was developed based on prior head injury code lists. Sensitivity and specificity of the final code list were calculated.ResultsThere were 2883 patients in the study population of whom 524 had AHT, 2123 had accidental injury, and 236 were indeterminate cases. The final list of AHT codes had a sensitivity of 76.1% (95% CI 72.5–79.8) and a specificity of 98.5% (95% CI 98.0–99.0) when limiting analyses to the groups with identified cause of injury (accidental vs abusive). Misclassification of cases based on codes resulting in false positives and false negatives was due to coding errors.ConclusionsThe list of ICD-10-CM codes can be utilized to identify and track cases of AHT at a national level in large administrative datasets though likely underestimates true injury burden.     

新生儿缺氧缺血性脑病磁共振影像学评分与临床分度的相关性研究

目的 探讨新生儿缺氧缺血性脑病（HIE）磁共振成像（MRI）影像学评分与临床分度的相关性。方法 依据HIE临床分度标准对61例HIE患儿进行分度,应用改良的MRI评分系统进行不同MRI序列的损伤评分,分析HIE影像学评分与临床严重程度之间的关系。结果 中度HIE的MRI影像学评分低于重度HIE,差异有统计学意义（P < 0.01）;0~7 d新生儿的MRI弥散加权成像（DWI）评分与MRI综合评分的相关系数最高（r > 0.9）;>7 d新生儿的MRI T1加权成像评分与MRI综合评分的相关系数最高（r=0.963）;重度HIE脑损伤的头部MRI表现主要以基底节/丘脑+脑干和全脑型损伤为主,而中度HIE以分水岭损伤为主、脑干很少受累,差异有统计学意义（P < 0.01）。结论 MRI影像学评分系统与HIE临床分度之间有较好的相关性,可协助HIE临床诊断及分度。     

磁共振成像和计算机断层扫描影像分度在评估新生儿缺氧缺血性脑病脑损伤程度中的价值

目的 探讨磁共振(MRI)和电子计算机断层扫描(CT)影像分度在评估足月新生儿HIE脑损伤程度中的价值.方法 35例足月HIE患儿于出生11 d内同步进行MRI及CT检查,并与临床分度进行比较.MRI主要观察和分度指标为T1WI、T2WI的异常信号灶;CT主要观察和分度指标为CT值、低密度灶、形态学情况及出血区.应用SPSS 13.0软件进行统计学分析.结果 35例足月HIE患儿MRI及CT影像分度与临床分度均有高度关连性(列联系数为0.723、0.731).HIE以临床表现为诊断标准,CT检出率为91.4%,假阴性率为8.6%,MRI检出率为100%.26例轻度HIE患儿中,临床与影像分度符合率为46.2%(CT)、61.5%(MRI);8例中度HIE患儿中,MRI检出6例、CT检出5例.在34例轻、中度HIE患儿中,MRI示2例基底核出血,发现率为5.9%;CT示9例蛛网膜下腔出血(l例合并脑室内出血),发现率为26.5%;1例重度HIE患儿MRI及CT均示多灶性出血.结论 新生儿HIE的诊断应以临床表现及临床分度为主,影像表现及分度仅作为诊断参考指征之一.MRI异常检出率较CT高,能更早检测出基底核损伤;而CT更能发现蛛网膜下腔出血.     

The neuroimaging mimics of abusive head trauma

Abusive head trauma (AHT) is a significant cause of morbidity and mortality in the paediatric population, typically in children under the age of two years. Neuroimaging plays a key role in the diagnostic work up of these patients as information regarding the mechanism of injury is often lacking and the findings on examination can be nonspecific.A number of conditions, both traumatic and atraumatic can mimic AHT based on neuroimaging features alone. The repercussions associated with a diagnosis or misdiagnosis of AHT can be severe and radiologists therefore need to be aware of and familiar with the imaging differentials of AHT.In this paper we review the imaging findings of the radiological mimics of AHT and focus on features that can help differentiate these entities from AHT.     

Lack of evidence for a causal relationship between hypoxic-ischemic encephalopathy and subdural hemorrhage in fetal life, infancy, and early childhood.

It has been asserted that hypoxic-ischemic encephalopathy (HIE) with cerebral swelling in the absence of marked trauma may be responsible for subural hemorrhage in the young. As this may have considerable implications in determining both the mechanism of death and the degree of force required to cause injury in certain cases of inflicted head injury in infancy, clarification is required. A retrospective study of 82 fetuses, infants, and toddlers with proven HIE and no trauma was undertaken from forensic institutes in Australia, the United Kingdom, Germany, Denmark, and the United States. The age range was 35 weeks gestation to 3 years, with a male to female ratio of 2:1. All cases had histologically confirmed HIE. Causes of the hypoxic episodes were temporarily resuscitated sudden infant death syndrome with delayed death (N = 30), drowning (N = 12), accidental asphyxia (N = 10), intrauterine/delivery asphyxia (N = 8), congenital disease (N = 6), aspiration of food/gastric contents (N = 4), inflicted asphyxia (N = 3), epilepsy (N = 1), dehydration (N = 1), drug toxicity (N = 1), complications of prematurity (N = 1), and complications of anesthesia (N = 1). The initiating event was not determined in 4 instances. In no case was there macroscopic evidence of subdural hemorrhage. In this study no support could be given to the hypothesis that HIE in the young in the absence of trauma causes subdural hemorrhage.     

Comparison of two neonatal ischemic injury models using magnetic resonance imaging

Using an 11.7-Tesla magnetic resonance imaging (MRI) scanner in 10-d-old rat pups we report on the evolution of injury over 28 d in a model of neonatal stroke (transient filament middle cerebral artery occlusion, tfMCAO) and a model of hypoxic-ischemic injury (Rice-Vannucci model, RVM). In both models, diffusion-weighted imaging (DWI) was more sensitive in the early detection of ischemia than T2-weighted imaging (T2WI). Injury volumes in both models were greater on d 1 for DWI and d 3 for T2WI, decreased over time and by d 28 T2WI injury volumes (tfMCAO 10.3% of ipsilateral hemisphere; RVM 23.9%) were definable. The distribution of injury with tfMCAO was confined to the vascular territory of the middle cerebral artery and a definable core and penumbra evolved over time. Ischemic injury in the RVM was more generalized and greater in cortical regions. Contralateral hemispheric involvement was only observed in the RVM. Our findings demonstrate that high-field MRI over extended periods of time is possible in a small animal model of neonatal brain injury and that the tfMCAO model should be used for studies of neonatal stroke and that the RVM does not reflect the vascular distribution of injury seen with focal ischemia.     

磁共振成像对新生儿缺氧缺血性脑病预后的早期评估

目的：了解足月新生儿缺氧缺血性脑病（HIE）的临床特点,探讨头颅磁共振成像对HIE预后的早期评估价值。方法：对近5年收治的348例足月新生儿HIE的临床资料进行回顾性分析,包括病史、临床表现、磁共振检查及随访结果等。结果：足月新生儿HIE占同期收治新生儿总数的8.25%,76.2%患儿由出生时窒息引起,其中轻度窒息占59.2%,重度窒息占40.8%。总的预后不良率为10.1%,其中重度脑病的预后不良率27.3%, 中度为10.0%, 轻度为1.5%。磁共振表现为弥漫性脑实质出血与脑梗死、基底节与内囊损伤、细胞毒性脑水肿时重度、中度、轻度脑病患儿的预后不良率分别是100%, 87.5%, 81.8%。结论：HIE仍是新生儿常见疾病,可导致死亡或遗留伤残;其中轻度窒息所占比例大,应引起重视。磁共振成像对预后具有早期判断价值,当出现弥漫性脑实质出血与脑梗死、基底节与内囊损伤、细胞毒性脑水肿时预后可能不良,尤其当两种或以上异常同时存在时。［中国当代儿科杂志,2007,9（5）：407-410］     

Pediatric blunt carotid injury: a review of the National Pediatric Trauma Registry.

Blunt carotid injury (BCI) is an uncommon yet potentially devastating entity which has received little attention in the pediatric literature. In an attempt to better characterize pediatric BCI, a review of the National Pediatric Trauma Registry was performed. Records were obtained from all children diagnosed with internal or common carotid injury associated with blunt trauma. The incidence of BCI was 0.03% (15 of 57,659 blunt trauma patients). Variables examined included: age, gender, mechanism of injury, associated injuries, various injury severity scores, and outcome. Various injuries were associated with an increase in BCI incidence including chest trauma (4-fold), combined head and chest trauma (6-fold), basilar skull fractures (4-fold), intracranial hemorrhage (6-fold), and clavicle fractures (8-fold). Thirty-three percent of the patients diagnosed with BCI suffered neurological complications directly attributable to their carotid injuries. Current practices regarding screening, diagnosis, and treatment are reviewed.     

新生儿缺氧缺血性脑病脑电背景演变与脑损伤程度的相关性研究

目的 探讨新生儿缺氧缺血性脑病（hypoxic-ischemic encephalopathy,HIE）患儿脑电图（electroencephalogram,EEG）背景演变与脑损伤程度之间的相关性。 方法 回顾性研究56例确诊为HIE并完善了连续视频脑电监测（continuous video electroencephalogram,cVEEG）与头部磁共振（magnetic resonance imaging,MRI）的患儿,根据临床症状分为轻度组（3例）、中度组（36例）、重度组（17例）,各组进行EEG背景分度及MRI脑损伤评分,分析EEG背景演变与脑损伤程度之间的关系。 结果 与中度组患儿相比,重度组胎龄小、生后5 min Apgar评分低、复苏评分高、脐动脉血或生后1 h内动脉血剩余碱低、机械通气比例高及短期不良结局发生率高（P<0.05）。轻中度组患儿头部MRI以无脑损伤（67%,2/3）和分水岭区损伤（67%,16/24）为主,62%（13/21）EEG在生后第3天内改善至轻度异常;重度组患儿头部MRI以基底节/丘脑+脑干（24%,4/17）和全脑型损伤（71%,12/17）为主,至生后第3天仍均为中重度异常。在生后第1天、第2天、第3天及第7~14天4个时间段EEG背景分度与临床症状分度、MRI评分及短期结局均具有相关性（P<0.01）。EEG分度与MRI评分的相关系数在生后第3天最高（r_s=0.751,P<0.001）,与临床症状分度（r_s=0.592,P=0.002）及短期结局（r_s=0.737,P<0.001）的相关系数在生后第7~14天最高;重度异常EEG患儿中无脑电活动者MRI评分最高,惊厥持续状态者次之,持续低电压者最低,差异有统计学意义（P<0.05）。 结论 HIE患儿的EEG背景分度与脑损伤程度之间有良好的相关性,可帮助早期评估脑损伤程度及预后。     

MRI对缺氧缺血性脑病患儿预后的评估价值

MRI为儿科影像检查中最重要的手段,具有很好的空间分辨率和时间分辨率,可呈现良好的解剖图像.通过弥散张量成像、磁共振波谱等功能MRI,可辅助鉴别缺血、缺氧、炎症、代谢性疾病等,尤其有助于评估HIE患儿的严重程度及神经预后.该综述基于国内外最新的研究进展,总结MRI尤其是功能MRI在HIE患儿神经预后评估中的价值.