Prolonged coma due to cerebral fat embolism: report of two cases

Fat embolism syndrome associated with atraumatic compartment syndrome of the bilateral upper extremities: An unreported etiology

Fat embolism syndrome (FES) is a potentially life-threatening condition that develops when fat embolism leads to clinical symptoms and multisystem dysfunction. The classic triad of respiratory distress, neurologic symptoms, and petechial rash are non-specific, and the lack of specific laboratory tests makes the diagnosis of FES difficult. Although FES is most common after long bone fractures, multiple conditions some of which are atraumatic have been associated with the development of FES. We report a case of FES that occurred in the setting of a non-traumatic compartment syndrome of the upper extremities. The pathologic and clinical findings, pathophysiology, diagnostic challenges, and pathologic methods to properly diagnose FES are discussed with a review of the relevant literature. This case highlights the importance of the autopsy in making a diagnosis of FES in cases where death could otherwise be incorrectly attributed to multi-organ system failure, shock, or sepsis.

Fat Embolism Syndrome Without Bone Fracture: Is It Possible?

BACKGROUND: Fat embolism syndrome is a life challenge syndrome. Early diagnosing and treatment can significantly improve the patient’s prognosis and likelihood of success. This syndrome occurs mainly after long bones fractures or orthopedic surgery up to 95% of diagnosed cases, but in unusual situation can be faced as well. These rare situations include diabetes mellitus, video-assisted thoracoscopies, fatty liver, and fat injection in plastic and cosmetic procedures. The likelihood of this syndrome can be increased if multiplex long bones fractures occur in the same patient simultaneously. This syndrome is usually manifested with respiratory changes (hypoxemia and ARDS), neurological focal symptoms (confusion, headache, aphasia, and hemiplegia), and skin abnormalities (petechias, and rush in conjunctiva and oral mucosa). The clinical scenario begins typically after 24−72 h of injury, and mainly, respiratory changes are the first, followed by neurological abnormalities and finally petechias as the most significant sign. CASE REPORT: In this case, we report a rare case of unexpected fat embolism syndrome after soft-tissue minimal trauma. This is the first case that we faced according to literature, and the aim of reporting this case is to emphasize that fat syndrome embolism can happen perhaps in every trauma patient even in minor soft-tissue trauma in absence of bone fractures. CONCLUSION: We strongly suggest that this case should make the physicians taking in consideration fat embolism syndrome even if bone fracture missed, to early diagnosing and adequately treating the patient, and optimizing his chances to survive.

Late-onset isolated cerebral fat embolism syndrome after a simple tibial plateau fracture: a rare case report

Fat embolism syndrome (FES) is a complication of long bone fractures that often occurs within 72 hours of injury. Early-onset isolated cerebral fat embolism is catastrophic and rarely reported. We herein present a rare case of delayed-onset isolated cerebral FES that developed 10 days after definite fixation of a left tibial plateau fracture. A 70-year-old woman was injured in a traffic accident and diagnosed with a left tibial plateau fracture. However, she developed sudden loss of consciousness (E4V1M1) and quadriplegia 10 days after fracture fixation. Her vital signs showed no respiratory distress. Diagnosis of isolated cerebral FES was made based on magnetic resonance imaging of the brain, the findings of which were compatible with the clinical neurological findings. After supportive care and rehabilitation, her consciousness became clear on the second day of admission, and her consciousness changed to E4V5M6. She gradually regained strength in her right limbs but had residual left limb paraplegia. Isolated cerebral FES should always be considered for patients who develop a change in consciousness, even beyond 72 hours after injury. Imaging may not initially show definitive abnormalities. Repeated magnetic resonance imaging should be considered if the initial clinical presentation does not fully meet Gurd's criteria.

Increase in optic nerve sheath diameter predicts early cerebral involvement in fat embolism syndrome

Early diagnosis of cerebral fat embolism in a patient with contradiction to MRI is challenging. Here we report an interesting case, where the raised optic nerve sheath diameter helped us to predict the early cerebral involvement with fat emboli in a left femoral shaft fracture patient. MRI scan could not be performed due to the presence of a metallic implant in the patient from a previous surgery. He was later diagnosed as an atypical presentation of fat embolism syndrome. Optic nerve sheath monitoring also helped us to guide further management of the patient.

Cerebral fat embolism in the absence of a long bone fracture: A rare case report

Background

The classic triad of fat embolism syndrome consists of pulmonary distress, mental status change, and petechial rash. Typically, symptoms manifest 24-48 hours after a long bone fracture, but case reports have demonstrated fat embolism syndrome without long bone fracture. These cases are initiated by a stress response, mobilizing free fatty acids into the circulation.

Case Description

Herein, we present the case of a 70-year-old male who presented with the left-sided hemiparesis and was subsequently found to have tandem lesions of the right internal carotid artery (ICA) and right middle cerebral artery (MCA) warranting emergent mechanical thrombectomy (MT). The ensuing pathology report determined the source of ischemic stroke to be caused by fat embolism, a rare and intriguing case of cryptogenic large vessel occlusion (LVO) with unique features distinguishing it from other reports in the literature.

Conclusion

According to the biochemical theory, a catecholamine surge can precipitate fat globules forming in the circulatory system, leading to tissue hypoxia, injury, and ischemia. While the majority of cerebral fat emboli cause reversible ischemia of small diameter vessels, our case presents with LVO and tandem lesions in both the ICA and MCA resulting in infarct and residual hemiparesis.

Spinal cord infarction as a rare complication of fat embolism syndrome following bilateral intramedullary nailing of femur fractures

Fat embolism syndrome (FES) is a rare and potentially fatal complication occurring most often after long bone or pelvic fractures and orthopaedic procedures. It can consist of pulmonary, central nervous system and cutaneous manifestations. The exact pathophysiology of emboli reaching the arterial circulation is poorly understood.1 It is suggested that this may occur by either 'paradoxical' embolism or microembolism.2 3 Its true incidence is unknown but increases in the presence of multiple closed fractures. It can be a diagnostic dilemma for clinicians and if suspected diffusion-weighted MRI is the modality of choice for the investigation of the central nervous system.4 We present the case of a 22-year-old man who developed multifocal cerebral infarcts, a right-sided cerebellar infarct and an infarct in the anterior cord bilaterally at the level of C5-C6 as a result of FES.

Neuroimaging findings in a case of cerebral fat embolism syndrome with delayed recovery

A young male with multiple lower limb fractures admitted to our Intensive Care Unit was diagnosed with cerebral fat embolism syndrome (FES) based on clinical features and initial magnetic resonance imaging (MRI) which showed multiple hyperintensities on T2-weighted imaging, involving bilateral cerebral and cerebellar hemispheres, predominantly in the watershed territory. The serial MRI done at 3 weeks showed more prominent and larger sized lesions which were in line with the patient's initial low Glasgow Coma Score and indicated severe cerebral insult. The patient responded well to supportive intensive care therapy; his neurological recovery though slow was consistent as he could return to his full functional status after 6 months. The follow-up MRI showed resolution of the most of earlier lesions. This indicates potentially good outcomes even in severe cases of cerebral FES with appropriate medical care.

Paradoxical cerebral fat embolism in revision hip surgery

The incidence of clinical fat embolism syndrome (FES) is low (<1%) whilst fat embolism (FE) of marrow fat appears to occur more often (Mellor and Soni (2001)). Paradoxical brain FE may occur in patients undergoing hip orthopedic surgery who have an undocumented patent foramen ovale (PFO). We report a case of an eighty-year-old male patient, who underwent a scheduled revision hip surgery suffering a paradoxical cerebral FE.

Cerebral fat embolism syndrome after long bone fracture due to gunshot injury

Cerebral fat embolism syndrome is a lethal complication of long-bone fractures and clinically manifasted with respiratory distress, altered mental status, and petechial rash. We presented a 20-year-old male admitted with gun-shot wounds to his left leg. Twenty-four hours after the event, he had generalized tonic clonic seizures, decorticate posture and a Glascow Coma Scale of seven with localization of painful stimuli. Subsequent magnetic resonance imaging of the brain showed a star-field pattern defining multiple lesions of restricted diffusion. On a 4-week follow-up, he had returned to normal neurological function. Despite the severity of the neurological condition upon initial presentation, the case cerebral fat embolism illustrates that, cerebral dysfunction associated with cerebral fat embolism illustrates reversible.

Late recovery in cerebral fat embolism

Fat embolism syndrome presenting primarily with cerebral manifestations is rarely reported. We report here two such patients who showed complete recovery following initial deterioration. The aim of these reports is to highlight that prolonged intensive care and good rehabilitation can lead to normal neurologic recovery despite poor clinical picture initially. The importance of adequate oxygenation to prevent secondary brain damage is emphasized during prolonged recovery.

Massive cerebral involvement in fat embolism syndrome and intracranial pressure management

Fat embolism syndrome (FES) is a common clinical entity that can occasionally have significant neurological sequelae. The authors report a case of cerebral fat embolism and FES that required surgical management of intracranial pressure (ICP). They also discuss the literature as well as the potential need for neurosurgical management of this disease entity in select patients. A 58-year-old woman presented with a seizure episode and altered mental status after suffering a right femur fracture. Head CT studies demonstrated hypointense areas consistent with fat globules at the gray-white matter junction predominantly in the right hemisphere. This CT finding is unique in the literature, as other reports have not included imaging performed early enough to capture this finding. Brain MR images obtained 3 days later revealed T2-hyperintense areas with restricted diffusion within the same hemisphere, along with midline shift and subfalcine herniation. These findings steered the patient to the operating room for decompressive hemicraniectomy. A review of the literature from 1980 to 2012 disclosed 54 cases in 38 reports concerning cerebral fat embolism and FES. Analysis of all the cases revealed that 98% of the patients presented with mental status changes, whereas only 22% had focal signs and/or seizures. A good outcome was seen in 57.6% of patients with coma and/or abnormal posturing on presentation and in 90.5% of patients presenting with mild mental status changes, focal deficits, or seizure. In the majority of cases ICP was managed conservatively with no surgical intervention. One case featured the use of an ICP monitor, while none featured the use of hemicraniectomy.

Cerebral fat embolism syndrome after simultaneous bilateral total knee arthroplasty: a case series

Total knee arthroplasty (TKA), particularly when performed as a simultaneous bilateral procedure, theoretically increases the risk for entry of fat globules into the blood stream. The frequency of cerebral fat embolism syndrome (CFES) was retrospectively investigated among 2345 simultaneous bilateral TKA procedures performed from August 2006 to May 2010. During that period, 9 patients presented with neurologic deficits after surgery and underwent brain magnetic resonance imaging. For identification of CFES among them, we used both magnetic resonance imaging findings and clinical criteria modified from the original one of Gurd and Wilson (J Bone Joint Surg Br 1974; 56B:408). Four patients fulfilled the modified criteria. The overall incidence of CFES occurring after simultaneous bilateral TKA was 0.17%. Cerebral fat embolism syndrome should be ruled out, although rare, in patients who present with neurologic impairment after TKA.

Cerebral Fat Embolism: A diagnostic challenge

Fat embolism syndrome (FES) is a rare but a serious clinical catastrophe occurring after traumatic injury to long bones. Cerebral involvement in the absence of pulmonary or dermatological manifestation on initial presentation may delay the diagnosis of cerebral fat embolism (CFE). We discuss a case series of CFE which posed a challenge in diagnosis. The clinical presentations of these patients did not satisfy the commonly used clinical criteria for aiding the diagnosis of FES. Early MRI brain (DWI and T2 weighted sequences) in patients with neurological symptoms after trauma even in the absence of pulmonary and dermatological findings should be the goal.

Cerebral fat embolism and the "starfield" pattern: a case report

Nearly all long-bone fractures are accompanied by some form of fat embolism. The rare complication of clinically significant fat embolism syndrome, however, occurs in only 0.9-2.2% of cases. The clinical triad of fat embolism syndrome consists of respiratory distress, altered mental status, and petechial rash. Cerebral fat embolism causes the neurologic involvement seen in fat embolism syndrome. A 19-year-old African-American male was admitted with gunshot wounds to his right hand and right knee. He had diffuse hyperactive deep tendon reflexes, bilateral ankle clonus and decerebrate posturing with a Glasgow Coma Scale (GCS) score of 4T. Subsequent MRI of the brain showed innumerable punctate areas of restricted diffusion consistent with "starfield" pattern. On a 10-week follow up he has a normal neurological examination and he is discharged home. Despite the severity of the neurologic insult upon initial presentation, the majority of case reports on cerebral fat embolism illustrate that cerebral dysfunction associated with cerebral fat embolism is reversible. When neurologic deterioration occurs in the non-head trauma patient, then a systemic cause such as fat emboli should be considered. We describe a patient with non-head trauma who demonstrated the classic "starfield" pattern on diffusion-weighted MRI imaging.

Reversible cytotoxic cerebral edema in cerebral fat embolism

We present a case of cerebral fat embolism (CFE) that demonstrated evidence of diffuse white matter cytotoxic edema on diffusion-weighted magnetic resonance imaging, in addition to punctate hyperintensities on T2-weighted and diffusion-weighted imaging. The case suggests that CFE represents a combination of occlusive arteriolar disease and secondary neurotoxicity.

Early Diagnosis of Cerebral Fat Embolism Syndrome by Diffusion-Weighted MRI (Starfield Pattern)

Background — Cerebral fat embolism syndrome is a rare, but potentially lethal, complication of long bone fractures. Neurological symptoms are variable, and the clinical diagnosis is difficult. The purpose of this case study is to demonstrate the value of diffusion-weighted MRI of the brain for early diagnosis of fat embolism syndrome.

Case Description — A non-head-injured 18-year-old woman suffered acute mental status changes 21 hours after an uncomplicated fracture of the left tibia. MRI of the brain was performed 48 hours after injury. T2-weighted images showed multiple nonconfluent areas of high signal intensity, which, on the diffusion-weighted scans, were revealed as bright spots on a dark background (“starfield” pattern). We suggest that this indicates areas of restricted diffusion that are due to cytotoxic edema, resulting from multiple microemboli.

Conclusions — High-intensity lesions in the brain on diffusion-weighted images may serve as an early-appearing and more sensitive indicator of the diagnosis of fat embolism in the clinical context of long bone injury without head trauma.