학술논문
A novel ventriculoperitoneal shunt flow sensor based on electrically induced spatial variation in cerebrospinal fluid charge density.
Document Type
Academic Journal
Author
Zarrin DA; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States.; Jafari M; Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, United States.; Kim W; Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, United States.; Colby GP; Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA, United States.
Source
Publisher: Frontiers Media S.A Country of Publication: Switzerland NLM ID: 101632513 Publication Model: eCollection Cited Medium: Print ISSN: 2296-4185 (Print) Linking ISSN: 22964185 NLM ISO Abbreviation: Front Bioeng Biotechnol Subsets: PubMed not MEDLINE
Subject
Language
English
ISSN
2296-4185
Abstract
Introduction: Ventriculoperitoneal (VP) shunts divert cerebrospinal fluid (CSF) out of cerebral ventricles in patients with hydrocephalus or elevated intracranial pressure (ICP). Despite high failure rates, there exist limited clinically viable solutions for long-term and continuous outpatient monitoring of CSF flow rate through VP shunts. We present a novel, low-power method for sensing analog CSF flow rate through a VP shunt premised on induced spatial electrical charge variation. Methods: Two geometric variants of the proposed sensing mechanism were prototyped: linear wire (P1) and cylindrical (P2) electrodes. Normal saline was gravity-driven through P1 and a commercially available shunt system in series. True flow rates were measured using a high-precision analytical balance. Subsequently, artificial CSF was driven by a programmable syringe pump through P2. Flow rate prediction models were empirically derived and tested. Sensor response was also assessed during simulated obstruction trials. Finally, power consumption per flow measurement was measured. Results: P1 (17 mm long) and P2 (22 mm long) averaged 7.2% and 4.2% error, respectively, in flow rate measurement from 0.01 to 0.90 mL/min. Response curves exhibited an appreciably flattened profile during obstruction trials compared to non-obstructed states. P2 consumed 37.5 µJoules per flow measurement. Conclusion: We propose a novel method for accurately sensing CSF flow rate through a VP shunt and validate this method at the benchtop with normal saline and artificial CSF over a board range of flows (0.01-0.90 mL/min). The sensing element is highly power efficient, compact, insertable into existing shunt and valve assemblies, and does not alter CSF flow mechanics.
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2024 Zarrin, Jafari, Kim and Colby.)
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
(Copyright © 2024 Zarrin, Jafari, Kim and Colby.)