Cerebral Spinal Fluid Shunt System with Dual Lumen Distal Catheter Redundancy to Minimize Revision Surgery

Abstract Significance: Cerebral spinal fluid (CSF) shunt failure resulting in revision surgery is a major problem for hydrocephalus patients. Up to 50% of shunts fail within two years of implant. A NIH funded expert panel has identified improved shunt design as a research priority to improve hydrocephalic patient outcomes. Occlusion is the most common CSF shunt failure mode, and little has changed with shunt failure rates over several decades of use. Innovation: The proposed product is a dual lumen distal catheter providing modular redundancy, a well-known principle for increasing reliability by duplicating critical components. This catheter design automatically reroutes flow through a pristine back-up channel upon occlusion of the primary channel, eliminating the need for surgical shunt revision. This technological innovation is low cost, low risk, and easy to implement novel shunt design compatible with current CSF shunt protocols. Hypothesis: Redundancy of the distal catheter flow channel can extend the working life of CSF shunts. Longer shunt life will reduce patient morbidity by preventing excessive intracranial pressures and by minimizing the need for costly revision surgery. Preliminary Data: Applicant has performed bench experiments demonstrating proof of concept for the dual lumen distal catheter. SBIR Phase I Project Objective: Develop a CSF shunt that minimizes the need for revision surgery. Aim 1: Freeze dual lumen distal catheter design for feasibility testing. Distal catheter design will be finalized to meet human use requirements based on (a) Aim 1 expert design input and CSF shunt supplier input (b) bench and in vitro design studies. Milestone: Design studies of dual lumen distal catheter prototypes will demonstrate the potential for meeting functional requirements. Aim 2: Dual lumen distal catheter feasibility testing. The objective is to generate test data demonstrating feasibility for SBIR Phase II further research, which will focus on distal catheter design verification testing for FDA submissions and clinical studies. Aim 1 distal catheters connected to currently marketed and FDA cleared CSF shunt valve and proximal catheter components will be assessed with results reported as descriptive analysis. The test devices will be sterilized and aged prior to testing. Aim 1 distal catheter design will be evaluated first with bench and in vitro tests (n=10 catheters per GLP test) and subsequently in vivo (n=16 catheters per GLP-like experiment) with four test animals. This feasibility testing will include commonly accepted functional requirements outlined in ISO 7197 as well as bench and in vitro testing of rerouting mechanism performance. Milestone: The dual lumen distal catheters will demonstrate feasibility by meeting functional test success criteria. .Narrative This project objective is to develop a Cerebral Spinal Fluid (CSF) shunt that minimizes the need for revision surgery that is a major problem for hydrocephalic patients with cerebral spinal fluid (CSF) shunts failing within the first and second year after implant. The proposed CSF shunt technological innovation is a low cost, low risk and easy to implement shunt design change compatible with current CSF shunt protocols that has the potential to minimize CSF shunt revision surgery.