Abstract WP253: Diagnostic Evaluation and Outcome of Cerebral Fat Embolism: Single Center Retrospective Review

Abstract

Introduction: Cerebral Fat Embolism (CFE) is an underappreciated complication of trauma and orthopedic surgery whose diagnosis is mostly based on clinical suspicion. The utility of diagnostic testing is poorly defined. Methods: Using discharge diagnosis codes and a stroke database at a Level 1 Trauma Center, we performed a retrospective chart review of diagnostic workup and outcome for CFE from 2005 to 2019. Among those with a diagnosis of systemic fat emboli syndrome after long-bone fracture, cerebral involvement was established based on altered mental status, retinal findings, brain MRI findings or a combination of these. This report focuses on those who had MRI, all of which had findings of CFE. Results: Forty patients with CFE were identified, comprising 0.3% of all patients admitted with long-bone fractures. Of these patients, the average age was 39 years (SD 22), 30 (75%) were men, 28 (70%) had hypoxemia, 2 (5%) had petechial rash, and 29 (73%) were comatose, including 16 (40%) following orthopedic surgery. Brain MRI findings of CFE included scattered diffusion-restriction (60%), confluent white-matter edema (33%) and diffuse petechial hemorrhage (30%), with 27% having multiple findings of CFE. Ophthalmologic evaluation revealed exudates or hemorrhage suggestive of Purtscher-like retinopathy in 20 (91%) of 22 patients examined. Transcranial doppler microembolic signals (MES) were detected in 17 (53%) of 32 patients examined and were associated with scattered diffusion-restriction on MRI (chi square, p =0.01). Twelve patients (30%) died before discharge, 15 (38%) were discharged to a nursing facility, 12 (30%) to a rehabilitation facility and 1 (3%) to home. After a mean of 5.4 months, 1 patient had died, 11 had severe disability and 16 had moderate disability or better. Conclusion: The diagnosis of CFE is complicated by unknown sensitivity of diagnostic modalities. Nonetheless, typical MRI and ophthalmologic findings can assist in diagnosis. MES are associated with scattered infarction on MRI, suggesting active disease. The outcome of patients with CFE is highly variable, and a better understanding of this potentially devastating disease will require studies with larger numbers of cases collected in a standard fashion at multiple trauma centers.