Long-Term Outcome in the Repair of Spinal Cord Perimedullary Arteriovenous Fistulas

Histogram detailing the location of the PMAVFs of the 29 patients evaluated at our institution.

A 27-year-old man with 18 months of progressive bilateral lower extremity weakness, urinary retention, and constipation. At presentation to our hospital, the patient was using crutches, had decreased sensation in both lower extremities, and loss of bowel and bladder function. His ALS scores on admission were 4 for ambulation and 3 for micturition. The patient underwent surgical correction of his type 2 PMAVF. At follow-up clinical evaluation 2 months after surgical correction, the patient had interval improvement in ambulation (ALS ambulation = 3) as well as micturition (ALS micturition = 2). A, From left to right: Myelogram shows serpiginous filling defects in the lower thoracic region. Sagittal T2-weighted MR image demonstrates cord edema extending to the conus medullaris with abnormal surrounding flow-voids. Sagittal T1-weighted postgadolinium MR image again shows abnormal vascular structures along the conus medullaris, worrisome for a spinal vascular malformation. B, Preoperative spinal angiogram. From left to right: Serial angiograms of a selective injection of the right T10 intercostal artery demonstrate supply of the perimedullary fistula via an ASA branch. C, Intraoperative indocyanine green angiography in the arterial (top) and venous (bottom) phases identifies 1 of the dominant feeders (arrow) of the perimedullary fistula. D, Intraoperative photographs again demonstrate 1 of the main feeding arteries (top, arrow) and placement of an arteriovenous malformation clip (bottom). E, First postoperative conventional spinal angiogram. From left to right: Serial angiograms of a selective injection of the right T10 intercostal artery demonstrate opacification of the anterior spinal artery with early shunt at the level of the surgical clips, consistent with a residual perimedullary fistula. The long arrow indicates a residual fistula site; the short arrow, early opacification of anterior spinal vein. F, Intraoperative photographs after rotation of the cord and conus medullaris demonstrate residual fistula along the anterior aspect of the cord fed by an ASA branch (top), which was treated with cauterization and placement of an AVM clip (bottom, arrow).

A 6-year-old girl with 3 weeks of waxing and waning abdominal pain, followed by headache and neck stiffness and progressive slowing of her gait. Review of the patient's history revealed a strong paternal family history of HHT. On presentation, her neurologic examination findings were unremarkable, except for 4/5 strength dorsiflexion of the bilateral lower extremities (ALS ambulation = 1, ALS micturition = 0). Lumbar puncture findings were consistent with SAH. The patient underwent endovascular correction of her type 3 PMAVF. The patient's neurologic examination findings returned to normal immediately postprocedure and remained normal on clinical follow-up at 4 months. A, Sagittal and coronal maximum-intensity-projection images of a contrast-enhanced CT scan of the spine demonstrate a large varix at the T8–9 level, with a tangle of draining veins extending inferiorly. B, From left to right: Serial angiograms of a selective injection of the right T10 intercostal artery demonstrate opacification of the feeding artery to the single-hole perimedullary fistula with a large partially thrombosed varix, corresponding to the enhancing “mass” identified on CT and the tangle of draining veins extending inferiorly. C, Left: Selective diagnostic catheter placement in the right T10 intercostal artery, with a microcatheter positioned within the varix. Right: Coil mass occupying the varix and the fistula site. Selective injection of the right T10 intercostal artery shows slow filling of the feeding vessel without any residual shunt. D, Lateral view of a selective injection of the right external carotid artery demonstrates exuberant vascularity of the nasal mucosa with microshunts and early opacification of the right ophthalmic vein, suggestive of the diagnosis of HHT.