[Clinical manifestation and imaging diagnostic analysis of fat embolism syndrome].

OBJECTIVE: To explore characteristics of clinical and imaging findings in patients with fat embolism syndrome. METHODS: From January 2021 to October 2022,clinical manifestations of 13 patients with fat embolism due to fracture or orthopaedic surgery were retrospectively analyzed,including 11 males and 2 females,aged from 17 to 60 years old. Mental and respiratory abnormalities and changes in vital signs occurred after admission or after surgery,and patient's chest and brain imaging results were abnormal. The patient's mental and respiratory abnormalities,vital signs,chest and brain imaging results were continuously monitored. RESULTS: The main clinical manifestations of fat embolism syndrome were abnormal pulmonary respiration in 13 patients,abnormal central nervous function in 7 patients,and spotted rash in 2 patients. Chest CT showed diffuse distribution of ground glass shadows in 13 patients,and severe symptoms were "snowstorm". Nine patients with ground glass fusion consolidation,5 patients with multiple nodules and 4 patients accompanied by bilateral pleural effusion. Head CT findings of 5 patients were negative,and head MRI findings of 1 patient showed multiple T1WI low signal,T2WI high signal shadow,DWI high signal shadow,and "starry sky sign" in basal ganglia,radiative crown,hemioval center,thalamus,frontal parietal cortex and subcortex. CONCLUSION: Fat embolism syndrome has a high mortality rate. Clinical manifestations of respiratory system and nervous system are not specific,and the skin spot rash has a characteristic manifestation. The "blizzard" sign is the specific manifestation of chest X-ray and CT examination of fat embolism,and the "starry sky" sign is the typical manifestation of diffusion-weighted sequence of brain MRI examination of fat embolism.

Fat embolism syndrome in Duchenne muscular dystrophy: Report on a novel case and systematic literature review.

We report a non-ambulatory 13-year-old boy with Duchenne muscular dystrophy who experienced severe acute respiratory distress syndrome and cerebral fat embolism following elective soft tissue surgery. Post-surgery radiological examination revealed bilateral femoral fractures and marked osteopenia that were believed to have caused disseminated pulmonary and cerebral fat embolism. The patient had never been on glucocorticoid treatment. Five months post-surgery, he remained in a state of minimal consciousness. A literature review was performed and eleven publications included, providing case reports of a total number of 23 patients with Duchenne muscular dystrophy with fat embolism syndrome. The most common causes were falls from the wheelchair that predominantly resulted in femoral fractures. Median age at the event was around 14 years. Seven patients succumbed to complications of fat embolism. No event was described in the context of surgery. We want to raise awareness that spontaneous unnoticed fractures may occur especially in adolescents with DMD from traumatic injury of large bones and also during elective surgery with a high risk of causing fat embolism with severe sequelae.

Low pressure headache and cerebral fat embolism from a sacral fracture through a Tarlov cyst: a case report.

BACKGROUND: Here we report the only formally documented case in the United Kingdom, to our knowledge, of a cerebral fat embolism secondary to non-iatrogenic trauma through a Tarlov cyst. This case demonstrates the pathology clearly giving an excellent opportunity to demonstrate a rarely seen pathology as well as illustrating the importance of the patient history to guiding further management. CASE PRESENTATION: A middle-aged patient was admitted on the acute medical take complaining of severe headache with photophobia, having just returned after a skiing holiday. Computerised tomography scan of the head showed fat within the anterior horn of both lateral ventricles, and within the subarachnoid space. Re-discussion with the patient and subsequent MRI (Magnetic Resonance Imaging) of the spine identified the pathogenesis of her symptoms: a sacral insufficiency fracture through a Tarlov cyst, causing subarachnoid fat embolism and symptoms of a low-pressure headaches due to a dural leak. Patient was medically managed and discharged with planned follow-up. Due to the Coronavirus pandemic and resolution of the patient's symptoms, they declined further follow up imaging. CONCLUSIONS: The case demonstrates a rarely seen pathology as cause of a common presenting problem, headache. Emphasizing the importance of history taking and appropriate investigations in medical cases that do not conform to the usual diagnosis.

Fat Embolism Syndrome Complicated by Diffuse Alveolar Hemorrhage After a Minimally Displaced Tibia Fracture: A Case Report.

CASE: A 26-year-old man with a minimally displaced tibial shaft fracture after an all-terrain vehicle crush injury rapidly developed fat embolism syndrome (FES), leading to diffuse alveolar hemorrhage (DAH) preoperatively. He was treated with an intramedullary rod 10 days after injury after a complicated clinical course and went on to full union with no long-term mental or systemic sequelae. CONCLUSIONS: FES is a known complication of long bone fractures, frequently presenting with hypoxemia. DAH is a rare complication of the condition. This case demonstrates the need for a high index of suspicion both for FES and DAH as complications of orthopaedic trauma.

Pulmonary CT imaging findings in fat embolism syndrome: case series and literature review.

BACKGROUND: Fat embolism syndrome (FES) is a rare life-threatening complication, which commonly affects the lung. Currently, the most widely accepted criteria for the diagnosis of FES are the Gurd and Wilson Criteria established nearly 40 years ago, but without pulmonary images involved. Our study aims to analyse the pulmonary computed tomography (CT) findings seen in FES. CASE PRESENTATION: This report enrolled four cases of FES with lung involvement. The mainly symptoms and signs included dyspnea, disturbance of consciousness, anemia, thrombocytopenia and, most notably, ground-glass opacities, septal thickening, ill-defined centrilobular nodules, and patchy consolidation were demonstrated on bilateral lungs. Combining the clinical manifestations and laboratory tests, the diagnosis of FES was confirmed. With the treatment of steroids, anti-coagulation and supportive treatment, the four patients' symptoms were relieved, abnormalities in chest CT were absorbed significantly and the patients were finally discharged. CONCLUSIONS: There are several common manifestations of FES in pulmonary CT images, and the lung parenchymal features give more information for the diagnosis of FES than the pulmonary vessel findings. Given the absence of a gold standard diagnostic test for FES, further investigation to explore new diagnostic criteria of FES involving pulmonary radiological features is needed in the future.

Cerebral fat embolism syndrome at a single trauma center.

OBJECTIVES: Based on a 16-year case series, we sought lessons about diagnosis and treatment of cerebral fat embolism syndrome. MATERIALS AND METHODS: Using discharge codes at a Level 1 Trauma Center, we performed a retrospective chart review of clinical characteristics, diagnostic studies, treatments, and outcome in cerebral fat embolism syndrome. RESULTS: Thirty-nine (40%) of 97 patients with fat embolism syndrome were diagnosed with cerebral fat embolism syndrome, with 29 (74%) presenting with coma. All had abnormal brain magnetic resonance imaging, with scattered cytotoxic edema (starfield pattern) in 29 (74%). All but two of the 21 patients with dilated fundoscopy showed retinal embolism. Among 29 patients with transcranial Doppler, the presence of microembolic signals in 15 (52%) was associated with fever (p = 0.039), right-to-left intracardiac shunting (p = 0.046) and a trend towards initial coma. In 11 patients with serial transcranial Dopplers and treatment with high-intensity statin therapy, the frequency of microembolic signals tended to decrease after therapy was initiated. Of the 28 (72%) of the 39 patients discharged, 16 (57%) had mild to moderate disability at last follow up. CONCLUSIONS: The recognition of cerebral fat embolism syndrome may be improved with routine inclusion of brain magnetic resonance imaging, dilated fundoscopy, and transcranial Doppler. We share our empiric management algorithm for cerebral fat embolism syndrome using these studies and with consideration of experimental therapies in select patients to prevent ongoing cerebral injury.

Susceptibility-weighted imaging of cerebral fat embolism: A case report.

RATIONALE: Cerebral fat embolism (CFE) is a rare but critical disease in a clinical setting. Considering that manifestations and CT findings of CFE tend to be atypical, this condition is very difficult to diagnose. The purpose of this article was to assess the value of susceptibility-weighted imaging (SWI) in the diagnosis of CFE. PATIENT CONCERNS: Our patient was an 80-year-old woman who developed hypoxemia, quadriplegia, and progressive confusion after fracture of the right femoral neck and right superior ramus of pubis within 24 hours. DIAGNOSIS: T2-weighted magnetic resonance imaging (T2 W MRI), fluid-attenuated inversion recovery sequences, and diffusion-weighted imaging showed numerous hyperintense foci in the subcortex and white matter of both cerebral hemispheres, some of which were confluent and SWI showed multiple symmetrical punctate microhemorrhages in both hemispheres. Base on the history and MRI findings, the patient was diagnosed with CFE. INTERVENTIONS: The patient received anticoagulation and lipid-lowering therapy. OUTCOMES: The patient regained consciousness, and her muscle strength in the limbs gradually recovered. One year after discharge, the patient could independently walk on her own. LESSION: This case report shows the characteristics of CFE on SWI, which can help clinicians in diagnosing which can help clinicians in diagnosing CFE.

Concomitant post-traumatic ocular and cerebral fat embolism syndrome and thrombotic pulmonary embolism: A case report.

RATIONALE: Fat embolism syndrome (FES) is composed of a triad of symptoms, including respiratory distress, neurologic deficit, and petechiae. Respiratory distress usually presents first before the other symptoms. Thrombotic pulmonary embolism (TPE) is a differential diagnosis of FES. Trauma is a risk factor for both diseases; however, co-occurrence is rare. PATIENT CONCERNS: A 35-year-old male patient presented with altered consciousness, focal neurologic deficit, and respiratory distress after a left femoral subtrochanteric fracture and subsequent open reduction and internal fixation with an intramedullary nail. DIAGNOSIS: Computed tomography pulmonary angiography (CTPA) revealed lower pulmonary artery filling defects and ground-glass opacities in bilateral lung, indicating TPE and FES, respectively. INTERVENTIONS: Heparin was initially added and subsequently switched to apixaban. The symptoms improved quickly without major bleeding complications. LESSION SUBSECTIONS: Concomitant TPE and FES after trauma are rare and require different treatment approaches. Due to clinical similarities, prompt chest CTPA was advised to detect TPE that was treated with anticoagulant therapy instead of supportive care for FES.

Fat embolism syndrome in a patient with a right undisplaced femoral neck fracture.

Fat embolism syndrome (FES) is a rare condition characterised by the classic triad of respiratory distress, neurologic symptoms and petechial rash. Here, we encountered a case of FES in a patient with an asymptomatic right undisplaced femoral neck fracture (Garden Stage II). FES was diagnosed based on the Gurd and Willson's diagnostic criteria and brain magnetic resonance imaging features. To the best of our knowledge, this is the first case of FES in a patient with an undisplaced femoral neck fracture. This study highlights the importance of considering the possibility of FES even in patients with undisplaced femoral neck fractures.

Label-Free Diagnosis of Pulmonary Fat Embolism Using Fourier Transform Infrared (FT-IR) Spectroscopic Imaging.

The diagnosis of pulmonary fat embolism (PFE) is of great significance in the field of forensic medicine because it can be considered a major cause of death or a vital reaction. Conventional histological analysis of lung tissue specimens is a widely used method for PFE diagnosis. However, variable and labor-intensive tissue staining procedures impede the validity and informativeness of histological image analysis. To obtain complete information from tissues, a method based on infrared imaging of unlabeled tissue sections was developed to identify pulmonary fat emboli in the present study. We selected 15 PFE-positive lung samples and 15 PFE-negative samples from real cases. Oil red O (ORO) staining and infrared spectral imaging collection were both performed on all lung tissue samples. And the fatty tissue of the abdominal wall and the embolized lipid droplets in the lungs were taken for comparison. The results of the blind, evaluation by pathologists, showed good agreement between the infrared spectral imaging of the lung tissue and the standard histological stained images. Fourier transform infrared (FT-IR) spectroscopic imaging significantly simplifies the typical painstakingly laborious histological staining procedure. And we found a difference between lipid droplets embolized in abdominal wall fat and lung tissue.

Radiological features of pulmonary fat embolism in trauma patients: a case series.

PURPOSE: Fat embolism syndrome (FES) is a rare complication in trauma patients (usually with long bone fractures) in which migrating medullary fat precipitates multiorgan dysfunction, classically presenting with dyspnoea, petechiae and neurocognitive dysfunction. Although this triad of symptoms is rare, it nonetheless aids diagnosis of pulmonary fat embolism (PuFE). Typical imaging features of PuFE are not established, although increasing use of CT pulmonary angiography (CTPA) in this cohort may provide important diagnostic information. We therefore conducted a case series of FES patients with CTPA imaging at a Level 1 Trauma Centre in Melbourne, Australia. METHODS: Medical records and various radiological investigations including CTPA of consecutive patients diagnosed clinically with FES between 2006 and 2018, including demographics, injury and their progress during their admission, were reviewed. RESULTS: Fifteen FES patients with retrievable CTPAs were included (mean age 31.2 years, range 17-69; 12 males [80%]). 93.3% had long bone fractures. CTPA was performed 2.00 ± 1.41 days post-admission. Review of these images showed pulmonary opacity in 14 (93.3%; ground-glass opacities in 9 [64.3%], alveolar opacities in 6 [42.9%]), interlobular septal thickening in 10 (66.7%), and pleural effusions in 7 (46.7%). Filling defects were identified in three (20%) CTPAs, with density measuring - 20HU to + 63HU. Ten patients (66.7%) had neuroimaging performed, with two patients demonstrating imaging findings consistent with cerebral fat emboli. CONCLUSION: CTPA features of PuFE are variable, with ground-glass parenchymal changes and septal thickening most commonly seen. Filling defects were uncommon.