Fourth ventricular subarachnoid stent for Chiari malformation type I-associated persistent syringomyelia

Area of Science:

• Neurosurgery
• Neurology
• Medical Devices

Background:

• Chiari malformation type I (CM-I) with syringomyelia is often treated with posterior fossa decompression.
• Persistent syringomyelia after decompression is uncommon and difficult to manage.
• Fourth ventricular subarachnoid stents are a preferred option for persistent syrinx with arachnoid scarring.

Purpose of the Study:

• Evaluate the safety and efficacy of fourth ventricle stents for persistent CM-I-associated syringomyelia.
• Assess dynamic syrinx dimension changes and stent durability.
• Report clinical outcomes and complications associated with stent placement.

Main Methods:

• Retrospective review of 13 patients with persistent CM-I-associated syringomyelia undergoing fourth ventricle stent placement.
• Data collected on demographics, clinical presentation, outcomes, and MRI findings.
• Maximal syrinx area calculated from T2-weighted MRI scans (preoperative, immediate, and late postoperative).

Main Results:

• Significant mean syrinx area reduction from 114.1 mm² to 24.5 mm² (p < 0.001).
• Average syrinx area reduction of 75.0% at a mean follow-up of 19.7 months.
• Variable resolution: 30.8% near-complete, 50% partial, 14.3% minimal reduction. One case of catheter migration.

Conclusions:

• Fourth ventricular subarachnoid stent placement is a safe and effective treatment for persistent CM-I-associated syringomyelia.
• The procedure significantly reduces mean syrinx area, with improved outcomes over longer follow-up.
• Stenting offers a viable therapeutic option for complex syringomyelia cases post-decompression.