Successful Management of Sacral Dural Arteriovenous Fistulas: A Case Series and Literature Review

Endovascular treatment of epidural arteriovenous fistula associated with sacral arteriovenous malformation: case report

Spinal epidural arteriovenous fistulas with sacral arteriovenous malformation (AVM) are a rare type of spinal arteriovenous fistulas. There are two varieties of spinal epidural arteriovenous fistulas (SEDAVFs), with type 1 involving intradural venous drainage and type 2 not involving intradural venous drainage. We present a case of transarterial embolization for type 1 SEDAVFs with sacral AVM. Within 8 months, a 14-year-old boy presented with progressively weaker lower extremities and bladder-bowel dysfunction. Magnetic resonance imaging (MRI) of the whole spine revealed thoracic spinal cord congestion, a single dilated flow void running from the lumbosacral area to the conus medullaris, and continuing cranial draining up to the C5 level via the perimedullary vein. Filling of the venous sac through a preferential feeder after embolizing the AVM nidus was performed. After 3 months, the clinical follow-up showed improvement of motoric function, although mild. Endovascular treatment for SEDAVF type 1 might have achieved total obliteration without any procedural complications. Nevertheless, it can be very challenging due to multiple feeders and the presence of an AVM nidus like in this case. However, the most difficult thing in fistula cases is establishing the diagnosis and finding the fistula point. Early treatment is required, due to the fact that longstanding lesions could cause irreversible damage.

Sacral dural arteriovenous fistula supplied by bilateral lateral sacral arteries: case report and literature review

Sacral dural arteriovenous fistulas (DAVFs) with bilateral arterial supplies are extremely rare. To date, only two cases with arterial supply from bilateral lateral sacral arteries (LSAs) were reported. We report a rare case of sacral DAVF with arterial supply from bilateral LSAs. A 56-year-old man presented with a 2-month history of progressive weakness and numbness in his lower extremities, along with urinary incontinence. Spinal magnetic resonance imaging (MRI) showed extensive edema of the spinal cord, vascular flow voids, and intraparenchymal enhancement. Spinal angiography revealed a spinal DAVF at the level of S1 supplied by bilateral LSAs and drained ascending into the perimedullary venous plexus. The fistula was successfully treated with endovascular embolization. Sacral DAVFs present various diagnostic and treatment difficulties because of the complex angioarchitecture. Successful management of these lesions requires a profound understanding of the variable patterns of arterial supply in this region.

A rare case of sacral epidural arteriovenous fistula with concomitant occult multiple lumbar epidural arteriovenous fistulas

We describe a rare case of sacral epidural arteriovenous fistulas (edAVFs) with atypical clinical course of treatment. A 78-year-old man with a history of spinal surgery presented progressive gait disturbance and urinary incontinence. Spinal angiography demonstrated a sacral spinal AVF fed by bilateral lateral sacral arteries, draining to the venous pouch with subdural drainage. The first treatment by direct interruption of a subdural drainer was incompletely finished. Postoperative reassessment by 3D imaging analysis led to the diagnosis of sacral edAVF and 3D understanding of its angioarchitecture. The second treatment by transarterial embolization (TAE) resulted in complete occlusion of a sacral edAVF. However, spinal venous congestion didn't improve, because the recruitment of occult edAVFs at the multiple lumbar levels and complex-shaped sacral ventral epidural venous plexus (VEP) were involved in the remnant of prior subdural drainage. The third treatment was performed by TAE for three occult edAVFs and the VEP compartment connecting between a patent edAVF and subdural drainage, which resulted in complete disappearance of spinal cord edema. Endovascular embolization of VEP compartment connecting to subdural drainage in addition to fistulous occlusion may be one of the treatment options for several edAVFs at the multiple spinal levels.

Clinical and radiographic characteristics of sacral arteriovenous fistulas: a multicenter experience

OBJECTIVE

Available data on management of sacral arteriovenous fistulas (sAVFs) are limited to individual case reports and small series. Management includes observation, endovascular embolization, or surgical ligation, with no clear guidelines on the optimal treatment modality. The authors' objective was to report their multiinstitutional experience with management of sAVF patients, including clinical and radiographic characteristics and postprocedural outcomes.

METHODS

The electronic medical records of patients with a diagnosis of spinal arteriovenous fistula treated from January 2004 to December 2019 at the authors' institutions were reviewed, and data were summarized using descriptive statistics, including percentage and count for categorical data, median as a measure of central tendency for continuous variables, and interquartile range (IQR) as a measure of dispersion.

RESULTS

A total of 26 patients with sAVFs were included. The median (IQR) age was 65 (57-73) years, and 73% (n = 19) of patients were male. Lower-extremity weakness was the most common presenting symptom (n = 24 [92%]), and half the patients (n = 13 [50%]) reported bowel and bladder sphincter dysfunction. The median (IQR) time from symptom onset to treatment was 12 (5.25-26.25) months. Radiographically, all patients had T2 hyperintensity at the level of the conus medullaris (CM) (n = 26 [100%]). Intradural flow voids were identified in 85% (n = 22) of patients. The majority of the lesions had a single identifiable arterial feeder (n = 19 [73%]). The fistula was located most commonly at the S1 level (n = 13 [50%]). The site where the draining vein connects to the pial venous plexus was seen predominantly at the lumbar level (n = 16 [62%]). In total, 29 procedures were performed: 10 open surgeries and 19 endovascular embolization procedures. Complete occlusion was achieved in 90% (n = 9) of patients after open surgery and 79% (n = 15) after endovascular embolization. Motor improvement was seen in 68% of patients (n = 15), and bladder and bowel function improved in 9 patients (41%). At last follow-up, 73% (n = 16) of patients had either resolution or improvement of the pretreatment intramedullary T2 signal hyperintensity.

CONCLUSIONS

T2 hyperintensity of the CM and a dilated filum terminale vein are consistent radiographic signs of sAVF, and delayed presentation is common. Complete occlusion was achieved in almost all patients after surgery, and endovascular embolization was effective in 70% of the patients. Further studies are needed to determine the best treatment modality based on case-specific characteristics.

Endovascular treatment of a sacral dural arteriovenous fistula

Spinal dural arteriovenous fistula (SDAVF) is a rare pathological communication between arterial and venous vessels within the spinal dural sheath. Clinical presentation includes progressive spinal cord symptoms including gait difficulty, sensory disturbances, changes in bowel or bladder function, and sexual dysfunction. These fistulas are most often present in the thoracolumbar region. Diagnoses of SDVAFs are commonly missed, possibly due to the low index of suspicion, non-specific symptoms and challenging imaging. In this case report, we describe a rare presentation of a sacral SDAVF which was detected by collective efforts between endovascular neurosurgery and interventional radiology. We outline the diagnostic and imaging challenges we faced to discover the fistula. In particular, mechanical pump injection instead of hand injection during angiography was required to reveal the fistula. Following identification, the fistula was successfully treated endovascularly by using onyx (ethylene vinyl alcohol glue), a less invasive alternative to surgical intervention.

Concomitant Sacral Dural Arteriovenous Fistula and Conus Medullaris Arteriovenous Malformation with Respective Drainage Veins: Case Report and Literature Review

BACKGROUND

Spinal dural arteriovenous fistulas (DAVFs) and spinal arteriovenous malformations (AVMs) are relatively rare. Moreover, multiple spinal cord vascular lesions in an individual, such as double DAVFs and DAVF with AVM, are extremely rare. To date, there are only several reported cases of concomitant spinal DAVFs and AVMs.

CASE DESCRIPTION

A 25-year-old woman presented with pain of the right lower limb persisting for 1 month. Spinal magnetic resonance imaging showed prominent signal flow voids in the lumbosacral canal. Spinal digital subtraction angiography (DSA) showed a sacral DAVF fed by the right lateral sacral artery and a spinal intradural AVM at the conus medullaris fed by the anterior spinal artery from the left T11 intercostal artery. The drainage veins in these 2 lesions were respective and without common anastomosis. The diagnosis of concomitant sacral DAVF and conus AVM was made. Microsurgery was performed to excise these lesions successfully in the same operation. The patient's symptoms gradually improved after surgery. Postoperative spinal DSA confirmed the complete disappearance of the 2 lesions.

CONCLUSIONS

The concomitant presence of sacral DAVF and conus AVM is extremely rare. Nonetheless, clinicians should be aware of the possibility of the coexistence of multiple types of spinal vascular lesions in a single patient.

The Shunt Point of the Sacral Dural Arteriovenous Fistula: A Case Report and Literature Review

BACKGROUND

The occurrence of sacral dural arteriovenous fistula (dAVF) is rare. The detailed vascular architecture of sacral dAVF, including 3-dimensional (3D) angiographic images with operative findings, has not been evaluated compared with that of the thoracic and lumbar levels. We report a case of sacral dAVF with 3D angiographic examination and operative findings, with a literature review.

CASE DESCRIPTION

A 60-year-old man presented with progressive urinary incontinence and gait disturbance. A sacral dAVF was detected at the S1-2 level. The shunt point was at the medial side of the line between the intermediate sacral crest and the most medial point of the L5 pedicle circle at the anterior posterior view of the angiography; we defined this type as the medial type. After embolization, latent inflow arteries were visualized ipsilaterally and contralaterally. During surgery, because of dAVF recurrence, a vascular tangle was found on the dura. The surgical interruption of the draining vein improved the patient's symptoms. From the literature review, 92% of cases had medial-type shunt point. It is possible for sacral dAVF to have multiple inflow arteries originating ipsilaterally or bilaterally, and a venous pouch.

CONCLUSIONS

The shunt point of sacral dAVF tended to be located medially, not in the sacral foramen. Sacral dAVF has unique angioarchitecture. The differentiation of dAVF from epidural arteriovenous fistula may not be easy in some cases of sacral lesions. Therefore, further studies with a larger number of patients focused on the detailed vascular architecture are needed.