MR Imaging Patterns of Cerebral Fat Embolism in Sickle Cell Disease: A Pictorial Review

Cerebral fat embolism (CFE) is a rare and often under-recognized complication of sickle cell disease (SCD) associated with high morbidity and mortality. The pathogenesis of fat embolism syndrome (FES) in SCD is not yet fully understood. It is thought to be caused by mechanical blockage or biochemical damage from fat microemboli in the bloodstream triggered by bone marrow necrosis, leading to multiorgan failure. The clinical diagnosis of CFE is challenging due to its nonspecific and variable clinical presentation and lack of definitive laboratory tests. Therefore, imaging, particularly MRI, is crucial in diagnosing and managing CFE. This article highlights the complex pathophysiology and diverse clinical presentations of CFE and FES in SCD and emphasizes the vital role of MRI in diagnosing CFE. MRI not only helps diagnose CFE but also provides critical insights into the pathophysiology of the disease by showing different and evolving imaging patterns of CFE across time. These patterns, categorized into acute, subacute, and chronic phases, help one understand the disease course, diagnosis, and management. The available literature on CFE and the differential diagnosis of MRI patterns are also reviewed in this article.

Learning Objective: To identify different MR imaging patterns of CFE in patients with SCD and highlight their evolution and differential diagnosis.