Improvement of paraplegia caused by spinal dural arteriovenous fistula by surgical obliteration more than 6 years after symptom onset

Abstract

Spinal dural arteriovenous fistulae (SDAVF) are acquired spinal vascular malformations, in which a small connection between a radicular artery and radicular vein causes venous hypertension, congestive myelopathy and infarction of the spinal cord. Here the case of a 47-year-old man is presented who had pain in his back irradiating to his right leg, numbness of his right leg as well as weakness of both legs. Urination was disturbed with detection of residual urine. Six weeks later he developed a progressive paraparesis of the legs. A T2 weighted MRI of the lower back showed intramedullary hyperintensity. A myelitis was assumed and treatment with acyclovir and dexamethasone was started. Nevertheless, he developed total paralysis of his legs. Six years later, re-evaluation of the initial MRI and a new MRI showed abnormal blood vessels on the dorsal side of the spinal cord, which had been overlooked at the first MRI examination. Spinal angiography demonstrated an arteriovenous fistula. Fistula obliteration was performed. Six months later he was able to stand with canes for 2 min and showed improvement in sensibility. The remarkable aspect of this case of SDAVF is the relevant improvement of complete paraplegia by surgical obliteration 78 months after onset of symptoms. The delay of more than 6 years between onset of first symptoms and final diagnosis underlines the difficulties in making a correct diagnosis of SDAVF. However, even after delayed diagnosis, surgical obliteration should be done, as improvement of neurological function can still be achieved.