Diagnosis and treatment of epidural empyema in a pygmy goat

Abstract

A mixed-breed pygmy goat was presented for nonambulatory tetraparesis. Neurological examination was consistent with a C6 to T2 myelopathy. Initially, the goat was treated medically. Forty-three days later, magnetic resonance imaging (MRI) revealed an extradural mass compressing the cervical spinal cord. Magnetic resonance attributes of the mass were consistent with a slow-growing, fluid-poor lesion. The spinal cord was surgically decompressed. Epidural empyema secondary to Fusobacterium necrophorum was identified. Postoperative care consisted of anti-inflammatory medication, antimicrobials, and physical therapy. Ability to walk occurred by day 14 after surgery. Despite prolonged recumbency before surgery, the goat was clinically normal, and antimicrobials were discontinued on day 60 after surgery. Key clinical message: Epidural empyema can cause a compressive myelopathy which may result in varying degrees of paresis/paralysis. Clinical resolution and return of normal function occurred following the use of MRI to plan surgical decompression combined with extended use of antimicrobials.

Figure 1

Radiographs of the caudal cervical vertebral column in a goat with epidural empyema. On the right lateral (A), R 30° ventral oblique (B), and ventrodorsal (C) projections, the left C5–C6 articular process joint and intervertebral foramen are smoothly expanded (black arrows), consistent with pressure atrophy. The left pedicle and cranial articular process of C6 are abnormally shaped (white arrow). Within the C6 vertebral foramen and left C5–C6 intervertebral foramen, there is a dense aggregate of stippled mineral.

Figure 2

Sagittal MR images of the cervical vertebral column of a goat with epidural empyema. An extradural lesion (arrow) is present which is hypointense on T2w (A), T1w (B), and T2w Dixon fat suppression (C) images. Peripheral enhancement is seen on T1w Dixon fat suppression after administration of contrast (D).

Figure 3

Magnetic resonance imaging study of the C6 vertebral region of a goat with epidural empyema. A — On transverse T2w at the cranial aspect of C6 vertebra, the spinal cord (white arrow) is severely flattened, taking on a crescent shape, and is displaced to the right by an extradural mass (open arrow) that has expanded the C6 vertebral foramen and depressed the left dorsal aspect of the vertebral body. Small fluid spaces are present at the center of the lesion (open arrowhead). Despite the remodelling of C6, the signal intensity of the C6 vertebra is normal. B — On the corresponding T1w image, a thin hyperintense rim (arrow) surrounds the mass. C — There is peripheral enhancement of the mass on post-contrast, T1w Dixon fat suppression images (arrowhead).