Access to the brain parenchyma using endovascular techniques and a micro-working channel

Area of Science:

• Neurosurgery
• Vascular Surgery
• Biomaterials Science

Background:

• Surgical access to the central nervous system (CNS) carries risks.
• Emerging therapies require advanced CNS access methods.
• Minimally invasive endovascular approaches warrant investigation.

Purpose of the Study:

• To assess the feasibility of creating an endovascular parenchymal micro-working channel to the CNS.
• To evaluate the long-term biocompatibility of a nitinol securing plug used in the trans-vessel wall technique.

Main Methods:

• Trans-vessel wall interventions were performed in macaque monkeys using a clinical angiography suite.
• Contrast agents and methylene blue were injected to test the micro-working channel.
• Nitinol plugs were implanted in swine for a 1-year biocompatibility study.

Main Results:

• The trans-vessel wall technique successfully created a micro-working channel for parenchymal and subarachnoid infusion in monkeys without acute bleeding.
• The nitinol plugs in swine were endothelialized and dislodged with minimal capsule formation.
• No arterial stenosis was observed in swine after 1 year, with normal animal behavior and blood results.

Conclusions:

• The trans-vessel wall technique is a viable method for brain intervention, enabling delivery and sampling via a micro-working channel.
• Nitinol implants demonstrate excellent biocompatibility when placed through arterial walls, unlike traditional stent placements.
• This endovascular approach offers a promising alternative to surgical CNS access with favorable long-term outcomes.