Neuroimaging findings of retroclival hemorrhage in children: a diagnostic conundrum

Vasospasm in Pediatric Subarachnoid Hemorrhage

Cerebral vasospasm (CV) is a common severe complication of subarachnoid hemorrhage (SAH), a severe type of intracranial bleeding that is uncommon in children. The purpose of this article is to review the current literature regarding this potentially devastating complication. CV may be asymptomatic and is less common in children compared to adults. Several molecular phenomena, including inflammatory ones, contribute to its pathophysiology. Better collateral circulation and higher cerebral blood flow are protective factors in children. When clinically apparent, CV may manifest as a change in the child's neurologic status or vital signs. CV can be diagnosed using brain vessel imaging, such as computed tomography angiography, magnetic resonance angiography, digital subtraction angiography, transcranial Doppler ultrasonography, and computed tomography perfusion. A reduction of < 50% in the artery's caliber confirms the diagnosis. Besides general supportive measures and causative treatment of SAH, CV management options include the administration of calcium channel blockers and neurointerventional approaches, such as intra-arterial vasodilators and balloon angioplasty. Long-term outcomes in children are usually favorable.

Traumatic retroclival hematoma complicated with hyponatremia and delayed traumatic intracranial hematoma in an adult: A case report

Intracranial hematoma is a common variety of brain insults in trauma. However, posterior fossa hematoma in the retroclival location is quite unusual. There are limited numbers of case reports regarding traumatic retroclival hematoma. Some are managed with surgery in this condition. We present a traumatic retroclival hematoma in a 34-year-old gentleman who sustained brain trauma in a motor vehicle accident. His condition was further complicated by hyponatremia and delayed traumatic intracerebral hematoma in a distant location. The only symptom he had later was severe headache which could be attributed to delayed traumatic intracerebral hematoma and hyponatremia. He was managed conservatively and discharged on the 12th day from the hospital.

Recurrent Cervical Subdural Bleeding Because of Atlantoaxial Instability in a Patient with Rheumatoid Arthritis: A Case Report

CASE

Atlantoaxial instability (AAI) is a frequent complication of rheumatoid arthritis (RA), but its involvement in intracranial bleeding is unclear. We present a young woman with history of systemic lupus erythematosus and RA who developed 3 episodes of subdural bleeding at the upper cervical spine and cranial level. Imaging tests showed signs of AAI with odontoid deformity. The case was interpreted as recurrent traumatic cervical subdural hemorrhage because of AAI. No new episodes occurred after surgical C1-C2 fixation.

CONCLUSION

We report a case that had the association of hemorrhage and C1-2 instability in a patient with RA and lupus erythematosus.

Traumatic retroclival epidural hematoma associated with reversible ipsilateral internal carotid artery stenosis

INTRODUCTION

Traumatic retroclival epidural hematoma is rare. It is more common in pediatrics than in adults. Although it has been known that these cases are frequently associated with abducens nerve palsy, internal carotid artery stenosis is rarely found with those hematomas.

CASE REPORT

An 8-year-old girl was transferred to our hospital following a traffic accident. She had clear consciousness with right abducens nerve palsy. Computed tomography revealed the left side of both retroclival hematoma without clival fracture and subarachnoid hemorrhage at the Sylvian fissure. She also had a fracture of left femoral neck and ipsilateral lung contusion. Magnetic resonance imaging revealed a retroclival hematoma located in the epidural space and severe stenosis of left internal carotid artery (ICA) from the cavernous to supraclinoid portion without evidence of brain contusion. She was managed conservatively, and her right abducens nerve palsy recovered completely without deterioration of other neurological findings. Neuroradiological findings suggested this ICA stenosis as traumatic dissection. She was discharged home 2 months after the traffic accident.

CONCLUSION

Retroclival epidural hematoma without clival fracture associated with ipsilateral ICA stenosis is extremely rare. Although the exact mechanism of the ICA stenosis remains unclear, cerebral vascular events should be considered in the cases with traumatic retroclival hematoma.

Pediatric Retroclival Epidural Hematoma in the Acute Trauma Setting: A Sign of Tectorial Membrane Stripping Injury

OBJECTIVE. A traumatic retroclival epidural hematoma is a rare imaging finding of severe cervical flexion-extension injury in the pediatric population. The purpose of our study was to identify pediatric patients with a retroclival epidural hematoma, record the hematoma size and extent, and examine the major craniocervical ligaments for injury. MATERIALS AND METHODS. Pediatric patients who suffered a retroclival epidural hematoma were identified retrospectively using the keywords "clivus," "epidural hematoma," and "retroclival" included in head CT reports between 2012 and 2019. The cervical and brain MRI examinations for these patients were reviewed for craniocervical ligament injury by two certified neuroradiologists. Detailed descriptions of patient injuries were recorded along with demographic information, clinical history, patient management, and outcome. RESULTS. Eleven pediatric patients were identified with an acute posttraumatic retroclival epidural hematoma with a mean anteroposterior dimension of 4.4 mm and craniocaudal dimension of 4.3 cm. All patients with a retroclival epidural hematoma who underwent subsequent cervical MRI had a stripping injury of the tectorial membrane (TM). Disruption of additional major craniocervical ligaments on MRI (alar ligament, transverse ligament, longitudinal ligaments, and ligamentum flavum) was relatively rare with the most common associated ligamentous injuries involving the anterior atlantooccipital membrane, apical ligament, and interspinous ligaments. None of the patients suffered a cervical cord or severe intracranial injury. The majority of the patients were managed conservatively with excellent clinical outcomes. CONCLUSION. A posttraumatic retroclival epidural hematoma in the pediatric population is a rare injury often identified initially by head CT and easily overlooked by the radiologist. We propose that a retroclival epidural hematoma in the pediatric population is a direct result of a significant flexion-extension force, with a subsequent stripping injury of the TM from the posterior clivus. Pediatric patients with a posttraumatic retroclival epidural hematoma on initial head CT should undergo a cervical MRI to evaluate the integrity of the TM and other craniocervical ligaments.

Retroclival epidural hematoma: A rare location of epidural hematoma, case report, and review of literature

Retroclival epidural hematoma in adults is uncommon. Although most cases are associated with craniocervical trauma, other mechanisms have been reported, such as coagulopathy, vascular lesions, and pituitary apoplexy. We report two adults diagnosed with retroclival epidural hematoma. One patient was an 89-year-old male with leukemia and thrombocytopenia who sustained a fall and developed a traumatic retroclival epidural hematoma with brainstem compression; surgery could not be performed due to his clinical condition and he died 5 days later. The other patient was a 78-year-old female with atrial fibrillation who developed a spontaneous retroclival epidural hematoma as a result of warfarin use; she was treated conservatively with anticoagulant reversal and methylprednisolone and was subsequently discharged without neurological deficit. Retroclival hematomas are primarily treated conservatively due to the difficulty of surgical approach. The bleeding mechanism and dural and venous anatomy of this region tend to limit hematoma expansion.

MRI Findings in Pediatric Abusive Head Trauma: A Review

Trauma is the most common cause of death and significant morbidity in childhood; abusive head trauma (AHT) is a prominent cause of significant morbidity and mortality in children younger than 2 years old. Correctly diagnosing AHT is challenging both clinically and radiologically. The primary diagnostic challenges are that the abused children are usually too young to provide an adequate history, perpetrators are unlikely to provide truthful account of trauma, and clinicians may be biased in their assessment of potentially abused children. The main radiological challenge is that there is no single imaging finding that is independently specific for or diagnostic of AHT. The radiological evaluation should be based on the multiplicity and severity of findings and an inconsistency with the provided mechanism of trauma. While the most common neuroimaging finding in AHT is subdural hemorrhage, other less well-known magnetic resonance imaging (MRI) findings such as the "lollipop sign" or "tadpole sign," parenchymal or cortical lacerations, subpial hemorrhage, cranio-cervical junction injuries including retroclival hematomas, as well as diffuse hypoxic brain injury have been identified and described in the recent literature. While AHT is ultimately a clinical diagnosis combining history, exam, and neuroimaging, familiarity with the typical as well as the less-well known MRI findings will improve recognition of AHT by radiologists.

Tectorial membrane injury in adult and pediatric trauma patients: a retrospective review and proposed classification scheme

BACKGROUND AND PURPOSE

Traumatic tectorial membrane injuries have different radiologic presentations in adult versus pediatric patients. The purpose of this study was to identify and classify the different types of tectorial membrane injuries that occur in the adult and pediatric populations.

MATERIALS AND METHODS

Patients who suffered tectorial membrane injury were identified retrospectively using the keywords 'tectorial membrane," "craniocervical ligament tear/injury," and "atlanto-occipital dissociation" included in radiology reports between 2012 and 2018 using Nuance mPower software. All relevant imaging studies were reviewed by two certificates of additional qualification-certified neuroradiologists. Detailed descriptions of injuries were recorded along with any relevant additional findings, including clinical history.

RESULTS

Ten adults and six pediatric patients were identified with acute traumatic injuries of the tectorial membrane. Ninety percent of the adult patients sustained complete disruptions inferior to the clivus, or subclival, with 22% of tears at the level of the basion and 78% at the level of the odontoid tip. In contrast, 83% of pediatric patients suffered a stripping injury of the tectorial membrane located posterior to the clivus, or retroclival. Stretch injuries of the tectorial membrane were identified in 10% of adults and 17% of pediatric patients. The juvenile-type injury, which causes retroclival epidural hematoma, was determined to preferentially occur in patients less than or equal to 14 years of age with a high level of statistical significance (p value = 0.0014).

CONCLUSIONS

A classification system for tectorial membrane injuries is proposed based on this data: type 1-retroclival stripping injury (more common in pediatric patients); type 2a-subclival disruption at the basion and type 2b-subclival disruption at the odontoid (both more common in adult patients); and type 3-thinning of the tectorial membrane.

Anatomical and Physiological Differences between Children and Adults Relevant to Traumatic Brain Injury and the Implications for Clinical Assessment and Care

General and central nervous system anatomy and physiology in children is different to that of adults and this is relevant to traumatic brain injury (TBI) and spinal cord injury. The controversies and uncertainties in adult neurotrauma are magnified by these differences, the lack of normative data for children, the scarcity of pediatric studies, and inappropriate generalization from adult studies. Cerebral metabolism develops rapidly in the early years, driven by cortical development, synaptogenesis, and rapid myelination, followed by equally dramatic changes in baseline and stimulated cerebral blood flow. Therefore, adult values for cerebral hemodynamics do not apply to children, and children cannot be easily approached as a homogenous group, especially given the marked changes between birth and age 8. Their cranial and spinal anatomy undergoes many changes, from the presence and disappearance of the fontanels, the presence and closure of cranial sutures, the thickness and pliability of the cranium, anatomy of the vertebra, and the maturity of the cervical ligaments and muscles. Moreover, their systemic anatomy changes over time. The head is relatively large in young children, the airway is easily compromised, the chest is poorly protected, the abdominal organs are large. Physiology changes—blood volume is small by comparison, hypothermia develops easily, intracranial pressure (ICP) is lower, and blood pressure normograms are considerably different at different ages, with potentially important implications for cerebral perfusion pressure (CPP) thresholds. Mechanisms and pathologies also differ—diffuse injuries are common in accidental injury, and growing fractures, non-accidental injury and spinal cord injury without radiographic abnormality are unique to the pediatric population. Despite these clear differences and the vulnerability of children, the amount of pediatric-specific data in TBI is surprisingly weak. There are no robust guidelines for even basics aspects of care in children, such as ICP and CPP management. This is particularly alarming given that TBI is a leading cause of death in children. To address this, there is an urgent need for pediatric-specific clinical research. If this goal is to be achieved, any clinician or researcher interested in pediatric neurotrauma must be familiar with its unique pathophysiological characteristics.

Isolated traumatic retroclival hematoma: case report and review of literature

BACKGROUND

Retroclival hematomas are a rare entity. The pathology can be categorized into epidural hematoma or subdural hematoma based on the anatomy of the tectorial membrane. Frequently, the etiology is related to accidental trauma, though other mechanisms have been observed, including coagulopathy, non-accidental trauma, and pituitary apoplexy. There have been only 2 prior cases where both epidural and subdural hematoma co-present.

CASE PRESENTATION

An 8-year-old male was involved in a high-speed motor vehicle accident. He presented with a Glasgow Coma Score (GCS) of 14 with bilateral abducens nerve palsies. Computed tomography (CT) revealed a hemorrhage along the dorsum sella, clivus, and dens. Magnetic resonance imaging (MRI) demonstrated the retroclival hematoma in both the subdural and epidural space. At discharge, 19 days after the accident, the abducens nerve palsies had resolved without medical or operative intervention.

CONCLUSION

Retroclival hematoma may present after trauma. Although most cases exhibit a benign clinical course with conservative management, significant and profound morbidity and mortality have been reported. Prompt diagnosis with close observation is prudent. Surgical management is indicated in the presence of hydrocephalus, symptomatic brainstem compression, and occipito-cervical instability.

Magnetic resonance imaging of traumatic injury to the craniovertebral junction: a case-based review

OBJECT

The craniovertebral junction (CVJ) is unique in the spinal column regarding the degree of multiplanar mobility allowed by its bony articulations. A network of ligamentous attachments provides stability to this junction. Although ligamentous injury can be inferred on CT scans through the utilization of craniometric measurements, the disruption of these ligaments can only be visualized directly with MRI. Here, the authors review the current literature on MRI evaluation of the CVJ following trauma and present several illustrative cases to highlight the utility and limitations of craniometric measures in the context of ligamentous injury at the CVJ.

METHODS

A retrospective case review was conducted to identify patients with cervical spine trauma who underwent cervical MRI and subsequently required occipitocervical or atlantoaxial fusion. Craniometric measurements were performed on the CT images in these cases. An extensive PubMed/MEDLINE literature search was conducted to identify publications regarding the use of MRI in the evaluation of patients with CVJ trauma.

RESULTS

The authors identified 8 cases in which cervical MRI was performed prior to operative stabilization of the CVJ. Craniometric measures did not reliably rule out ligamentous injury, and there was significant heterogeneity in the reliability of different craniometric measurements. A review of the literature revealed several case series and descriptive studies addressing MRI in CVJ trauma. Three papers reported the inadequacy of the historical Traynelis system for identifying atlantooccipital dislocation and presented 3 alternative classification schemes with emphasis on MRI findings.

CONCLUSIONS

Recognition of ligamentous instability at the CVJ is critical in directing clinical decision making regarding surgical stabilization. Craniometric measures appear unreliable, and CT alone is unable to provide direct visualization of ligamentous injury. Therefore, while the decision to obtain MR images in CVJ trauma is largely based on clinical judgment with craniometric measures used as an adjunct, a high degree of suspicion is warranted in the care of these patients as a missed ligamentous injury can have devastating consequences.