Cerebrospinal Fluid Purification System

Abstract

The present invention provides methods and systems for conditioning cerebrospinal fluid (CSF). The methods provide for efficiently removing target compounds from CSF. The systems provide for a multilumen flow path and exchange of a majority volume portion of CSF in the CSF space. The removal and / or delivery of specific compounds can be tailored to the pathology of the specific disease. The removal is targeted and specific, for example, through the use of specific size-exclusion thresholds, antibodies against specific toxins, and other chromatographic techniques, as well as delivery and / or removal of targeted therapeutic agents. The invention finds use as a diagnostic, therapeutic and drug delivery platform for a variety of diseases affecting the CNS by accessing the CSF space. Exemplified disease conditions treatable by the present CSF processing systems and methods include, but are not limited to: Cerebral Vasospasm, Guillain Bane Syndrome, illustrating multi-lumen lumbar approach Alzheimer's, Parkinson's, Huntington's, Multiple Sclerosis, Amyotrophic Lateral Sclerosis, Spinal Cord Injury, Traumatic Brain Injury, Stroke, Cancer affecting the brain or spinal cord, Prion disease, Encephalitis from various causes, Meningitis from various causes, diseases secondary to enzymatic or metabolic imbalances, Biological Warfare, etc. For the first time, the present invention offers patients a disease-modifying, disruptive technology treatment platform that addresses the known disease pathogenesis of a number of neurologic conditions to which there are presently limited and ineffective treatment options.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS[0001]The present application claims the benefit of U.S. Provisional Application No. 60 / 828,745, filed on Oct. 9, 2006, the entire disclosure of which is hereby incorporated herein by reference for all purposes.FIELD OF THE INVENTION[0002]The invention pertains generally to medical devices and methods. More particularly, the present invention relates to devices, systems methods and kits for removal of toxins from the cerebrospinal fluid (CSF). More specifically, the method and system can be used to diagnose and treat disorders affecting the central nervous system (CNS) by measuring and modifying the chemical composition of CSF.BACKGROUND OF THE INVENTION[0003]Others have described devices for the handling and / or removal of cerebrospinal fluid (CSF) to and from a patient.[0004]For example, several patents disclose various methods for diverting or shunting CSF from the CSF space (ventricle, spinal column) to another portion of the body (e.g., ab...

AI Technical Summary

Benefits of technology

[0041]In some embodiments, the methods further comprise the step of mixing the conditioned CSF with unconditioned CSF as the conditioned CSF is returned to the CSF space. In some embodiments, the methods comprise inducing a turbulent flow as the conditioned CSF is returned which enhances mixing. For example, the turbulent flow can be created by introducing a multilumen catheter comprising one or more helical flow paths, textured (e.g., ribbed or bumped) flow paths, a T-separated flow path, bellows, balloons, fins, and / or multiple exit ports (e.g., side holes or side vents). Turbulent flow can also be induced by high pressure injection (i.e., “jetting”) or directed outflow.

[0042]In some embodiments, the conditioning comprises removing a targeted molecule (e.g., protein, peptide, oligopeptide) from the CSF. For example, the conditioning can comprise one or more separation processes selected from the group consisting of biospecific affinity (e.g., antibodies, nucleic acids, receptors, enzymes), immunoaffinity, cationic exchange, anionic exchange, hydrophobicity and various size exclusion thresholds.

Problems solved by technology

Others have described administering therapeutic agents to the CSF space, but do not disclose removing the CSF.

Others disclose removing CSF, but generally do not administer therapeutic agent or any other fluid.

Devices exist having both input and output catheters for administering therapeutic agents or synthetic CSF and removing endogenous CSF, but the close spatial placement of the inflow and outflow catheters do not allow for flow of CSF throughout the cerebrospinal fluid space or full CSF exchange that provides access to the complete intracranial and intraspinal CSF volume.

Such an apparatus is unnatural in that it requires flushing the entire system with an artificially produced solution rather than removing the toxins of interest from the patient's endogenous CSF, requires liters of instilled replacement fluid to be delivered on a regular basis, is neither targeted nor focused for removal of specific toxins of interest and is only practical in an acute setting where liters of fluid could be instilled.

Various devices aimed at accessing the CSF or indirectly targeting the nervous system exist, however there exists no CSF purification system that allows for the direct, targeted, logical and disease-specific removal of one or more of target compounds or the use of a dual or multi-lumen catheter that influences or controls CSF flow, mixing and efficiency of turnover.

Such a system has several inherent limitations.

The rate at which the concentration of toxic species is lowered is mediated by passive flow, is very slow, addresses only a fraction (milliliters) of the total CSF volume per hour, is not targeted or focused in removing specific items of interest and does not prevent reabsorption of toxic species back into the systemic circulation and thereby back into the CSF.

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