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History:

10 days history of progressive paraparesis evolved to paraplegia.
Acute onset of paraparesis initially. Was started on corticosteroids at the referring veterinarian.

Study performed:

Magnetic resonance imaging of the thoracolumbar spine is available for interpretation in multiple planes and sequences pre- and post-contrast administration. Sequences included sagittal STIR, T2, T1, T1+C, T2*, Transverse T2, HASTE, T2*, T1 and T1+C.

T2w sagittal, lumbar spine

HASTE sagittal, lumbar spine

T1w sagittal, pre-contrast

STIR sagittal

T2w transverse

T2*

T1w FS +C

Findings

  • The cranial mesenteric and celiac artery are at the level of L1-L2.
  • At the level of L2-L3, there is focal intramedullary lesion which is centrally located in the spinal cord but extends slightly more so on the right side.
  • This lesion is T2, STIR and T1 hyperintense and surrounded by a hypointense ring on T2 and STIR. There is no significant contrast enhancement noted after gadolinium administration.
  • On the gradient echo sequence there is evidence of magnetic susceptibility artifact associated with part of the lesion.
  • At the level of L1-L2 the intervertebral disc is slightly shorter in height when compared to the adjacent intervertebral discs. Focally the hyperintense signal associated with the CSF and epidural fat is partially disrupted ventrally (image 13/25 on the T2 transverse).
  • Cranial to main lesion, dorsal to L1-L2, there is a mild linear hyperintensity on T2 which is T1 isointense and does not contrast enhance superimposed with the central canal and most appreciated on the sagittal view.

    Conclusions:

  • Changes at the level of L1-L2 are most consistent for a haemorrhagic intramedullary lesion mostly in the late subacute phase consistent with the 10 days history of neurological signs. It is likely that this is secondary to high velocity disc extrusion at the level of L1-L2 due to its location just dorsal to the disc space and the appearance of the disc space when compared to the remainder of the disc spaces.
  • Secondary syringohydromyelia.
  • Outcome/ Follow up
  • The dog began showing signs of clinical improvement and was discharged home with cage rest, nursing care and medications. The patient was later lost to follow up.
  • Comments: This case is a classic illustration of the appearance of hemorrhagic lesion over time. Given the clinical history of the patient, the lesion’ characteristics corroborate the timing of a late subacute phase.

    References:

Schaller B. State-of-the-art imaging in stroke. Nova Biomedical. (2007) ISBN:1600215009.

Bradley WG. MR appearance of hemorrhage in the brain. Radiology. 1993;189 (1): 15-26.

An, Daegi, Junyong Park, Jong-Il Shin, Hyung-Joong Kim, Dong-In Jung, Ji-Houn Kang, Gonhyung Kim, Dong-Woo Chang, Jung-Hyang Sur, and Mhan-Pyo Yang. 2015. ‘Temporal Evolution of MRI Characteristics in Dogs with Collagenase-Induced Intracerebral Hemorrhage’, Comparative medicine, 65: 517-25.

Grand DJ, Woodfield CA, Mayo-Smith WW. Practical Body MRI: Protocols, Applications and Image Interpretation (Cambridge Medicine). Cambridge University Press. ISBN:1107014042. Leyendecker JR, Brown JJ, Merkle EM. Practical Guide to Abdominal and Pelvic MRI. LWW. ISBN:1605471445.

Linfante I, Llinas RH, Caplan LR et-al. MRI features of intracerebral hemorrhage within 2 hours from symptom onset. Stroke. 1999;30 (11): 2263-7.