Unrecognized Synergistic Effect of Spinal Epidural Lipomatosis on Spinal Stenosis and Its Radiological Grading: A Case Series.

Spinal epidural lipomatosis (SEL) is characterized by an excessive accumulation of epidural fat. It often exacerbates spinal stenosis and dural compression when combined with degenerative changes, leading to low back pain, radiculopathy, or myelopathy. Despite its increasing prevalence given rising obese population, the contribution of excessive epidural fat to spinal stenosis remains underrecognized on magnetic resonance imaging (MRI). This case series included four patients (aged 25-72 years) with varying degrees of SEL, lumbar spondylosis, and spinal stenosis. The clinical presentations were discussed. The amount of epidural fat on their lumbosacral spine MRI were graded by Borré classification (based on dural sac to fat ratio and epidural fat percentage), and the dural sac deformities were shown. We aim to improve radiologists' awareness on routine evaluation of epidural fat and its synergistic effect on spinal stenosis when combined with lumbar spondylosis to achieve early diagnosis. This serves to improve patient's outcome as SEL can be reversed by conservative treatment, and its association with metabolic syndrome further potentiate timely risk factor control to avoid cardiovascular disorders.