Intramedullary Hemorrhage Caused by Lumbosacral Epidural Arteriovenous Fistula with Dual Retrograde Perimedullary Venous Draining Routes: A Case Report and Review of the Literature

A Case of Rivaroxaban-induced Hematomyelia of Thoracic Spinal Cord in Patient with Acute Renal Failure

Hematomyelia associated with direct oral anticoagulants (DOACs) is rare. In this report, a case of a 78-year-old male with paraplegia due to hematomyelia after medication of rivaroxaban, which is the first case in which acute renal failure is closely associated with the onset and underwent surgical evacuation is presented. The patient was initially misdiagnosed as a spinal cord infarction, and appropriate therapeutic intervention was not provided. One year later, the patient's symptoms did not improve, he is dependent on a wheelchair for daily activities, and cystostomy was performed. During administration of DOACs, hemorrhagic lesion should be strongly suspected in a patient with acute renal failure.

Onyx embolization of a spinal epidural hemorrhage caused by thoracic spinal epidural arteriovenous fistula: A case report and literature review

Spinal epidural hemorrhages (SEDH) caused by spinal epidural arteriovenous fistulas (SEAVFs) are rare; thus, their specific pathogenesis has not been explained. Furthermore, the standard treatment for SEAVFs has not yet been defined. Here we report the case of a 36-year-old Chinese man who experienced acute onset chest pain and tightness. His symptoms rapidly aggravated until the lower limbs were unable to support him. Spinal magnetic resonance angiography (MRA) revealed a localized SEAVF and a secondary spinal cord lesion at the T4 level. Digital subtraction angiography (DSA) confirmed the presence of the SEDH/SEAVF at the T3-4 level with the left radicular artery feeding the fistula. Based on DSA and MRA findings, SEDH, local spinal cord infarction, and spinal venous reflux disorder were conditionally diagnosed. Using the arterial route, Onyx-34 was injected into the fistula to embolize the feeding arteries and the venous system. Angiography was performed after the microcatheter was withdrawn, and no residual fistula or anterior spinal artery was observed. The six-week follow-up MRI showed acceptable healing of the SEAVF, and the patient improved neurologically. This case suggests that endovascular treatment with Onyx-34 embolization should be considered a promising treatment strategy for this type of complicated SEAVF.

Sacral dural arteriovenous fistula of the filum terminale coexisting with partially thrombosed filum vein: A case report and literature review

Background:

Filum terminale arteriovenous fistulas (FTAVFs) are rare and usually classified as intradural ventral AVFs or Type IVa perimedullary fistulas, located on the pia surface along the course of filum terminale internum (FTI). We report an extremely rare case of sacral dural arteriovenous fistula of the FT. We also review the occurrence of FTAVFs in the sacral region.

Case Description:

A 64-year-old man presented with progressive weakness of the lower extremities for 3 months and bowel/bladder dysfunction following long history of back pain radiating to both legs. Magnetic resonance imaging of the lumbosacral and thoracic spine showed spinal cord congestion, extending from the conus medullaris to the level of T3, and partial thrombosis within the abnormal tortuous and dilated flow void, running from the sacral area to conus medullaris. Further findings were compression fracture of L2 vertebra, Grade I degenerative spondylolisthesis at the level of L2-3, and L3-4, and spinal stenosis at L2-3, L3-4, and L4-5. Spinal angiography, maximum intensity projection reformatted image of angiographic computerized tomography, and three-dimensional reconstructed image clearly demonstrated dural AVF of the FT at the level of S2 supplied by bilateral lateral sacral and middle sacral arteries with cranial drainage to perimedullary vein through the enlarged vein of the filum. The patient was indirectly treated by transection of the filum terminale and the draining vein at the level of L5 rostral to the fistula.

Conclusion:

Sacral DAVFs of the FT are extremely rare. In our case, the formation of fistula may cause by venous hypertension secondary to partial thrombosis within the filum vein, probably resulting from long-standing spinal canal stenosis. Sacral FTAVFs may be found on the pia surface of the terminal FTI, dural component at the area of dural sac termination, or dural extension covering the filum terminale externum.

Spinal epidural arteriovenous fistula with intradural venous reflux: The possibility of acquired origin caused by spinal stenosis and/or disc herniation

BACKGROUND

Spinal epidural arteriovenous fistulas (SEAVFs) are relative rare lesions. The pathogenesis of these fistulas remains unclear. Our aim is to review cases of SEAVFs at our institution.

METHODS

We reviewed a consecutive series of spinal vascular disease at our institution and collected all patients harboring SEAVFs. Medical charts were retrospectively reviewed regarding patient demographic data (i.e., gender and age), presenting symptoms and signs, previous history of spinal surgery or trauma, treatment methods, and neurological outcome after treatment. All image studies, including plain radiography, spinal MRI, MRA, and angiography were analyzed.

RESULTS

We identified 9 cases of lumbosacral SEAVFs with intradural venous reflux treated at our institution from June 2010 to August 2020. Their median age was 67 years, range 52-83 years. Only one patient had a history of trauma. Interestingly, our observations found that all fistulas are associated with spinal stenosis and/or disc herniation. An additional literature search about SEAVFs coexisting with spinal stenosis and/or disc herniation was performed and found another 19 cases with median age 69 years, range 39-83 years. Only 2 patients had a history of previous spinal surgery. The level of shunted pouch in all 28 patients was correlated with the level of spinal canal stenosis and/or disc herniation.

CONCLUSIONS

Our study may provide an additional evidence supporting an acquired etiology of SEAVFs, which mainly manifest in late adulthood. It is possible that spinal stenosis and/or disc herniation may result in thrombosis or impairment of venous drainage, causing increased venous pressure, leading to fistulous formation.