Primary conus medullaris arteriovenous shunt and secondary lumbo-sacral epidural arteriovenous fistula: One malformation can hide another

Cauda equina arteriovenous fistula supplied by proximal radicular artery and concomitant sacral dural arteriovenous fistula: A case report and literature review

Background

Cauda equina arteriovenous fistulas (AVFs) fed by the proximal radicular artery are exceedingly rare. Spinal dural arteriovenous fistulas (DAVFs) in the sacral region are rare and usually misdiagnosed. We report a case of a cauda equina AVF with concomitant sacral DAVF. We also review the coexistence of multiple types of spinal vascular malformations in a single patient.

Case Description

A 54-year-old man presented with progressive weakness of the lower extremities for 1 month. Magnetic resonance imaging (MRI) of the lumbosacral and thoracic spine showed spinal cord congestion, extending from the conus medullaris to the level of T7, and abnormal tortuous and dilated flow void, running from the level of L5 to T12 along anterior surface of the spinal cord. Spinal angiography demonstrated the fistula at the level of L2 below the conus medullaris. Based on intraoperative findings, the cauda equina AVF supplied by the proximal radicular artery with cranial drainage through the enlarged radicular vein was confirmed and successfully obliterated. Another enlarged arterialized radicular vein running parallel to another cauda equina nerve root is observed with unknown origin. After the operation, the patient showed mild improvement of his symptoms. Follow-up MRI and contrast-enhanced MR angiography revealed an another sacral DAVF vascularized by the lateral sacral artery.

Conclusion

The coexistence of different spinal vascular malformations in a same patient is extremely rare. Most authors of several studies hypothesized that venous hypertension and thrombosis due to the presence or treatment of the first spinal vascular lesion may produce a second DAVF.

Natural history and management of spinal cord arteriovenous shunts in pregnancy: A monocentric series of 10 consecutive cases with emphasis on endovascular treatment

PURPOSE

Intradural spinal cord arteriovenous shunts (IDSCAVS) are rare and constitute a challenging situation if symptoms occur during pregnancy. We present a series of ten such cases referred to our center: five cervical, four thoracic and one lumbar.

METHODS

We retrospectively reviewed our global series of 215 IDSCAVSs between 2002 and March 2020 and found ten patients who had presented during pregnancy. Clinical, radiological and therapeutic data were studied.

RESULTS

Seven shunts were AVM type niduses and three were micro AV-fistulae. All were associated with pial venous reflux and six hemorrhagic cases had pseudo aneurysms. Symptoms occurred mainly during the third trimester, 80% of patients presented with hemorrhage and spinal cord dysfunction. We embolized seven patients and proposed surgery in one, always after delivery: all recovered well. One woman declined treatment; one other was operated in emergency but did not improve. Mean follow-up was 3.9 years (0.5-19 years).

CONCLUSIONS

Despite this small group of patients, our initial experience of IDSCAVSs diagnosed during pregnancy indicates that embolization is an effective management strategy if performed after delivery and a recovery period. Results indicate that IDSCAVSs seem to have a low risk of early rebleedings after the ictal event and may be closely followed up until delivery. The results obtained show good clinical outcome without long-term rebleeds. Women with known IDSCAVSs should not be discouraged from becoming pregnant, however it seems wise to embolize them before pregnancy in order to offer protection against risks during pregnancy.