MRI Case Report: Fibrocartilageneus Embolus - FCE

 

Avi Avner  Bsc BVSc CVR MRCVS DVDI

 

History

A 2-year-old male Pitbull was presented with acute onset of right fore- limb paralysis which progressed rapidly into concurrent right hind limb paresis

 

Neurological exam

Neurological exam reviled right fore-limb paralysis with no deep pain sensation and absence of withdrawal reflex and flaccid muscle tone.

Right pelvic limb showed paresis with reduced propioception.

Additionally Horne’s syndrome (miosis, enophthalomos,ptosis and protrusion of the 3rd eyelid) was noted.

 

Localization of spinal lesion

Cervicothoracic Syndrome (C6-T2)

 

Differential Diagnoses

Fibrocartilageneous embolus

Explosive disc extrusion

Hemorrhage/ infarction

 

Further Investigation: MRI

 

MRI of the cervico-thoracic spine.

Figure 1 is T1W sagittal image of the cervical spinal cord. The image shows well the normal anatomy of the cervical spine and disk spaces.

 

MRI T1W
Pic 1: T1W sagittal image of the cervical spinal cord 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig 2 & 3 are T2W sagittal and axial images of the cervical spinal cord. The sagittal image demonstrates normally hydrated (hyperintense) disk spaces. At the level of C6-7 there is mild to moderate spinal cord swelling with intramedullary oval hyperintensity  (arrows) signifying oedema and possibly small amount of fluid  (infracted area) within the cord. The axial T2W image clearly depicts a round focal hyperintense lesion (arrows) within the grey matter on right side of the cord.

NOTE:  In cases with FCE survey spinal radiographs are unremarkable and there is no evidence of spinal cord compression on Myelo-CT, though occasionally focal swelling of the spinal cord may be detected. Therefore MRI is the only imaging modality that could demonstrate the FCE lesion.

 

MRI T2W axial MRI T2W
Pic 3: T2W axial images of the cervical spinal cord.   Pic 2: T2W sagittal images of the cervical spinal cord.   

 

 




 

 

Diagnosis

The acute onset of the clinical signs, which appeared dramatically lateralized without evidence of distinct neck pain and the dog’s signalment were highly suggestive of FCE.

The MRI findings confirmed the suspicion of FCE

 

Pathogenesis of FCE

FCE is a syndrome in which fibrocartilage identical to that found in the nucleus pulposus embolizes to the spinal cord vasculature, producing an area of ischaemic necrosis centered on the spinal cord grey matter. Signs are often lateralized, as the embolus, usually lodges in one branch of the ventral spinal artery.

 

Treatment

Treatment centers on successful rehabilitation of the animal. Improvement can be dramatic over the first 7 days and will continue for 1-3 months after injury. The extent of recovery will depend on the extent and magnitude of injury.