Methods and devices for treatment of vascular defects

Abstract

Devices and methods for treatment of a patient's vasculature with some embodiments configured for delivery with a microcatheter for treatment of the cerebral vasculature of a patient. Some embodiments include thin permeable membranes configured to occlude blood flow therethrough.

Description

FIELD OF THE INVENTIONGenerally, embodiments of devices and methods herein are directed to blocking a flow of fluid through a tubular vessel or into a small interior chamber of a saccular cavity within a mammalian body. More specifically, embodiments herein are directed to devices and methods for treatment of a vascular defect of a patient including some embodiments directed specifically to the treatment of cerebral aneurysms of patients.BACKGROUNDThe mammalian circulatory system is comprised of a heart, which acts as a pump, and a system of blood vessels which transport the blood to various points in the body. Due to the force exerted by the flowing blood on the blood vessel the blood vessels may develop a variety of vascular defects. One common vascular defect known as an aneurysm results from the abnormal widening of the blood vessel. Typically, vascular aneurysms are formed as a result of the weakening of the wall of a blood vessel and subsequent ballooning and expansion of the ...

AI Technical Summary

Benefits of technology

Some embodiments of a device for treatment of a patient's vasculature include an expandable body support structure. The expandable body support structure may include a low profile radially constrained state with an elongated tubular configuration that includes a first end, a second end, a longitudinal axis and elongate flexible struts disposed substantially parallel to each other with first ends thereof secured to a first ring and second ends thereof secured to a second ring. The first and second rings may be disposed substantially concentric to the longitudinal axis, and a middle portion of the expandable body may have a first transverse dimension with a low profile suitable for delivery from a microcatheter. The expandable body may also have an expanded relaxed state

Problems solved by technology

Due to the force exerted by the flowing blood on the blood vessel the blood vessels may develop a variety of vascular defects.

If, for example, an aneurysm is present within an artery of the brain, and the aneurysm should burst with resulting cranial hemorrhaging, death could occur.

Unfortunately, surgical techniques for treating these conditions include major surgery procedures which often require extended periods of time under anesthesia involving high risk to the patient.

Vaso-occlusive coils are commonly used to treat cerebral aneurysms but suffer from several limitations including poor packing density, compaction due to hydrodynamic pressure from blood flow, poor stability in wide-necked aneurysms and complexity and difficulty in the deployment thereof as most aneurysm treatments with this approach require the deployment of multiple coils.

In the treatment of cerebral aneurysms, covered stents or stent-grafts have seen very limited use due to the likelihood of inadvertent occlusion of small perforator vessels that may be near the vascular defect being treated.

In addition, current uncovered stents are generally not sufficient as a stand-alone treatment.

Thus, they do not block enough flow to cause clotting of the blood in the aneurysm and are thus generally used in combination with vaso-occlusive devices, such as the coils discussed above, to achieve aneurysm occlusion.

A number of aneurysm neck bridging devices with defect spanning portions or regions have been attempted, however, none of these devices have had a significant measure of clinical success or usage.

A major limitation in their adoption and clinical usefulness is the inability to position the defect spanning portion to assure coverage of the neck.

Existing stent delivery systems that are neurovascular compatible (i.e. deliverable through a microcatheter and highly flexible) do not have the necessary rotational positioning capability.

Another limitation of many aneurysm bridging devices described in the prior art is the poor flexibility.

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