What are some risk factors for epidural abscess?
Immunosuppression (e.g. diabetes, HIV); vertebral column related (e.g. intervention, trauma); potential infectious source (e.g. sepsis, IVDU).
How does spinal cord become damaged?
Either through direct compression by the abscess or via ischaemia/infarction from septic thrombophlebitis.
How does the epidural space become infected?
Haematogenous (two-thirds) or contiguous (one-thirds) spread.
Anterior T2 hyperintense extradural collection with peripheral enhancement extends from above the imaged vertebrae to the mid-sacrum, with associated mild posterior displacement of the theca.
Hyperintensity of a markedly narrowed L3/4 intervertebral disc is on sagittal T2 fat suppressed images, within destructive change within the posterosuperior aspect of the L4 endplate. Bone marrow oedema signal is noted within the L3/4 vertebral bodies.
Conclusion:
Anterior thoracolumbar epidural abscess extending from thoracic-midsacrum likely relating to discitis/osteomyelitis of L3/4.