Presentation
Suspected of having lumbar stenosis with contraindication to perform an MRI. He was complaining of bilateral lower limb weakness for several months.
Patient Data
Anteroposterior projection of a myelography of the dorso-lumbar junction. A serpiginous structure has been identified centrally in the spinal canal extending between T10 and T12 level that has been confirmed on the CT performed just after. The serpiginous structure is extending mainly posteriorly to the spinal cord, inside the dural sac and above the cauda equina level with no evidence of spinal canal stenosis. Thus, it represents a dilated vascular structure in keeping with a spinal dural arteriovenous fistula (SDAVF).
Case Discussion
Spinal dural arteriovenous fistula is the most common vascular spinal malformation. It represents an abnormal communication between the arterial and venous systems (radiculopial artery into a radicular vein). Subsequent venous system hypertension will occur leading to cord edema and eventually progressive myelopathy.
Symptoms are non-specific with insidious onset, delaying the diagnosis (pain, weakness, paresthesia, incontinence …).
Angiography is the gold standard imaging technique as well as a modality of treatment (endovascular technique versus surgical approach). If not contraindicated, MRI is generally the first performed imaging technique. It can show the abnormal signal of the cord as well as the abnormal vessels and rule out other differential diagnosis. CT angiography and myelography can also detect this pathology in certain conditions.
After treatment, improvement of the symptoms is variable depending on their types and chronicity.