Case Study

CT Right Sided Compressive Mineralized Extruded Disc Lesion in a 3 year old M Cavalier mixed dog

History of hemilaminectomy performed 12/2014. Acute onset yesterday of hind leg weakness after playing with another dog. Ambulatory but falling over after a few steps. RDVM took radiographs, gave dexamethasone injections and prescribed oral prednisone and buprenorphine as followup. Owner has not noted urination or defecation since yesterday. Decreased appetite, is drinking water. No vomiting. No history of seizures. Allergic to tramadol. Owner is giving buprenorphine (0.3mg/ml) 0.63ml orally bid, has not started the prednisone yet.

Physical exam: BAR, BCS 6/9. Mild amount of dental tartar, abdomen tense on palpation, urinary bladder moderately full. Weakly ambulatory with rear limb paresis. Pain score (Colorado 0-4) was 1/4 on epaxial palpation. Mentation alert. CP deficits in rear limbs. Spinal reflexes intact. Panniculus reflex intact on right side to mid-lumbar region, absent on left side. Cervical manipulation was non-painful. Epaxial palpation was tense in cranial lumbar region. Withdrawal intact on all limbs. Intact pain sensation in all limbs.

DX

Extradural right sided compressive mineralized extruded disc lesion centered at L3. Probable origin L2-3 disc space. Previous hemilaminectomy site at T11-13 right sided.

Image Interpretation

Survey Thoracolumbar CT: Previous hemilaminectomy performed at T11-T13 (right sided). There is still insitu disc mineralization at T11-12.There is no evidence of mineralized disc or other extradural compressive lesion seen at the previous hemilaminectomy site. Large volume of mineralized right sided extradural lesion at L3. Insitu disc material noted at L2-3 and immediately dorsal to that disc site indicating probable origin. However, the material extends throughout the length of L3. Additionally there is small volume in situ disc mineralization within the L3-L4 disc space.