Intraspinal canal platform system for coil embolization of anterior spinal artery aneurysm associated with spinal cord arteriovenous malformation: a case report and literature review

BACKGROUND

The prognosis for spinal artery aneurysms associated with spinal cord arteriovenous malformations (AVMs) is poor because of the high rupture rate of aneurysms. However, endovascular treatment remains technically difficult because the catheter system must be constructed via the small-caliber anterior spinal artery (ASA) or posterior spinal artery (PSA), which feeds functionally eloquent spinal cord. A 2.6F Carnelian HF-S microcatheter (Tokai Medical Products, Aichi, Japan) has been specifically designed to assist a 1.6F Carnelian MARVEL S microcatheter (Tokai Medical Products) as a small-profile 'platform catheter' close to the target lesion. Here we present a prenidal ASA aneurysm treated using a 2.6F Carnelian HF-S microcatheter as an intraspinal canal platform catheter and review related literature.

CASE PRESENTATION

A 50-year-old man presented with a subarachnoid haemorrhage due to cervical spinal cord AVM. Diagnostic vertebral angiography revealed the AVM supplied by the PSA originated from the right C2 segmental artery and ASA arising from the right V4 segment. Superselective angiography for each feeder was achieved through a 2.6F Carnelian HF-S microcatheter, and a prenidal ASA aneurysm was diagnosed, which was clinically consistent with haemorrhagic origin. A 1.6F Carnelian MARVEL S microcatheter was cannulated into the aneurysm through the 2.6F Carnelian HF-S microcatheter positioned at the ASA. The aneurysm coiling was successfully performed without system instability or periprocedural complications.

CONCLUSIONS

Only a few cases have described endovascular treatment for spinal artery aneurysms. To date, no reports have been published regarding the use of an intraspinal canal platform catheter to treat spinal artery aneurysms. A 2.6F Carnelian HF-S microcatheter served as a useful intraspinal canal platform catheter for coil embolization of the ASA aneurysm. This system can provide excellent accessibility and controllability for endovascular treatment of spinal artery lesions.

Factors Associated with Rapidly Deteriorating Myelopathy in Patients with Spinal Arteriovenous Shunts

Spinal arteriovenous (AV) shunts are rare conditions that sometimes present with myelopathy symptoms. The progression of the symptoms is usually gradual; however, some cases show rapid deterioration. We retrospectively investigated the factors that induced the rapid deterioration of myelopathy symptoms in patients with spinal AV shunts. We treated 33 patients with myelopathy with spinal AV shunts at our institutions, eight of whom experienced rapid deterioration (within 24 hours: 24.2%). Of these, three were related to the body movement or particular postures associated with playing golf, 30 minutes of Japanese straight sitting, and massage care. One patient showed deterioration after embolization for a tracheal aneurysm. The remaining four patients received steroid pulse therapy (high-dose steroid infusion) shortly before the rapid deterioration. These symptoms stopped progressing after cessation of steroid use. While positional or physical factors contributing to myelopathy deterioration might exist, we could not identify specific factors in this study. Nevertheless, rapid deterioration was frequently observed after high-dose steroid use. We must take care not to administer high-dose steroids for myelopathy caused by spinal AV shunt disease.

Neurosurgical versus endovascular treatment of spinal dural arteriovenous fistulas: a multicenter study of 195 patients

OBJECTIVE

The purpose of the present study was to compare the treatment success rates of primary neurosurgical and endovascular treatments in patients with spinal dural arteriovenous fistulas (dAVFs).

METHODS

Data from 199 consecutive patients with thoracic and lumbosacral spinal dAVFs were collected from 18 centers. Angiographic and clinical findings, the rate of initial treatment failure or recurrence by procedures, risk factors for treatment failure, complications, and neurological outcomes were statistically analyzed.

RESULTS

Spinal dAVFs were frequently detected in the thoracic region (81%), fed by a single feeder (86%), and shunted into an intradural vein via the dura mater. The fistulous connection between the feeder(s) and intradural vein was located at a single spinal level in 195 patients (98%) and at 2 independent levels in 4 patients (2%). Among the neurosurgical (n = 145), and endovascular (n = 50) treatment groups of single dAVFs (n = 195), the rate of initial treatment failure or recurrence was significantly higher in the index endovascular treatment group (0.68% and 36%). A multivariate analysis identified endovascular treatment as an independent risk factor with significantly higher odds of initial treatment failure or recurrence (OR 69; 95% CI 8.7-546). The rate of complications did not significantly differ between the two treatment groups (4.1% for neurosurgical vs 4.0% for endovascular treatment). With a median follow-up of 26 months, improvements of ≥ 1 point in the modified Rankin Scale (mRS) score and Aminoff-Logue gait and Aminoff-Logue micturition grades were observed in 111 (56%), 121 (61%), and 79 (40%) patients, respectively. Independent risk factors for lack of improvement in the Aminoff-Logue gait grades were multiple treatments due to initial treatment failure or recurrence (OR 3.1) and symptom duration (OR 1.02).

CONCLUSIONS

Based on data obtained from the largest and most recently assessed multicenter cohort, the present study shows that primary neurosurgery is superior to endovascular treatment for the complete obliteration of spinal dAVFs by a single procedure.

Microsurgical versus endovascular treatment of spinal epidural arteriovenous fistulas with intradural venous drainage: a multicenter study of 81 patients

OBJECTIVE

Spinal arteriovenous shunts are rare vascular lesions and are classified into 4 types (types I-IV). Due to rapid advances in neuroimaging, spinal epidural AVFs (edAVFs), which are similar to type I spinal dural AVFs (dAVFs), have recently been increasingly reported. These 2 entities have several important differences that influence the treatment strategy selected. The purposes of the present study were to compare angiographic and clinical differences between edAVFs and dAVFs and to provide treatment strategies for edAVFs based on a multicenter cohort.

METHODS

A total of 280 consecutive patients with thoracic and lumbosacral spinal dural arteriovenous fistulas (dAVFs) and edAVFs with intradural venous drainage were collected from 19 centers. After angiographic and clinical comparisons, the treatment failure rate by procedure, risk factors for treatment failure, and neurological outcomes were statistically analyzed in edAVF cases.

RESULTS

Final diagnoses after an angiographic review included 199 dAVFs and 81 edAVFs. At individual centers, 29 patients (36%) with edAVFs were misdiagnosed with dAVFs. Spinal edAVFs were commonly fed by multiple feeding arteries (54%) shunted into a single or multiple intradural vein(s) (91% and 9%) through a dilated epidural venous plexus. Preoperative modified Rankin Scale (mRS) and Aminoff-Logue gait and micturition grades were worse in patients with edAVFs than in those with dAVFs. Among the microsurgical (n = 42), endovascular (n = 36), and combined (n = 3) treatment groups of edAVFs, the treatment failure rate was significantly higher in the index endovascular treatment group (7.5%, 31%, and 0%, respectively). Endovascular treatment was found to be associated with significantly higher odds of initial treatment failure (OR 5.72, 95% CI 1.45-22.6). In edAVFs, the independent risk factor for treatment failure after microsurgery was the number of intradural draining veins (OR 17.9, 95% CI 1.56-207), while that for treatment failure after the endovascular treatment was the number of feeders (OR 4.11, 95% CI 1.23-13.8). Postoperatively, mRS score and Aminoff-Logue gait and micturition grades significantly improved in edAVFs with a median follow-up of 31 months.

CONCLUSIONS

Spinal epidural AVFs with intradural venous drainage are a distinct entity and may be classified as type V spinal vascular malformations. Based on the largest multicenter cohort, this study showed that primary microsurgery was superior to endovascular treatment for initial treatment success in patients with spinal edAVFs.