Cited 0 time in webofscience Cited 0 time in scopus

Fabrication and characterization of magnetically actuated flexible microrobot based on guidewire for intravascular treatment

Title
Fabrication and characterization of magnetically actuated flexible microrobot based on guidewire for intravascular treatment
Translated Title
혈관 질환 치료를 위한 가이드와이어(Guidewire)기반의 의료용 마이크로로봇 제작 및 성능평가
Authors
Lee, Jeong Hun
DGIST Authors
Lee, Jeong Hun; Choi, Hong Soo; Choi, Ji Woong
Advisor(s)
Choi, Hong Soo
Co-Advisor(s)
Choi, Ji Woong
Issue Date
2017
Available Date
2017-01-18
Degree Date
2017. 2
Type
Thesis
Keywords
Flexible microrobotReplica molding methodMagnetic actuationFinite element method (FEM)Intravascular treatment
Abstract
In this research, medical microrobot based on guidewire was fabricated for intravascular treatment such as chronic total occlusion (CTO). Chronic total occlusion (CTO) is totally clogged vessel disease for two or more months. Percutaneous coronary intervention (PCI) procedure is conventional treatment method using medical tools such as guidewire, balloon catheter, and stent. Guidewire takes a role to be guidance toward the lesion in human body with path of blood vessel. However, this guidewire has low controllability due to manipula-tion by operator’s hand. To increase controllability of guidewire for enhanced percutaneous coronary intervention (PCI) procedure, a flexible microrobot for medical tool was used at the guidewire. Structure of this flexible microrobot consist of the permanent magnet, beam, and connector. The proposed cylindrical microrobots were successfully fabricated by a replica molding method with polydimethylsiloxane (PDMS) material for formability, flexibility, and biocompatibility. This fabricated microrobot was attached to tip of guidewire using epoxy. Steering experiments of flexible microrobot were conducted by controlling external magnetic field. This magnetic field was generated by half-sphere type eight electromagnetic coil sys-tem (Minimag) using current control. Flexible microrobot was deformed toward all of direc-tion under magnetic field. Deformation angle of flexible microrobot is maximum almost 80 degrees at the magnetic field with 15 mT of intensity and 170 degrees of direction. Also, this results were compared with analytic solution driven by Euler-Bernoulli beam theory and fi-nite element method (FEM) analysis of multiphysics modeling. Designed microrobot for im-provement of performance of guidewire was conducted in vitro experiments in blood vessel phantom to confirm track-ability. Flexible microrobots was confirmed to success until 60 de-grees of branch angle in blood vessel phantom. Also, Flexible microrobot based on guide-wire was demonstrated in blood vessel networks phantom with multiple branch. This re-search confirmed the remotely steerable microrobot with magnetic actuation and track-ability of microrobot based on guidewire. Flexible microrobot based on guidewire was shown pos-sibility of robotic assisted percutaneous coronary intervention (PCI) for intravascular treat-ment. ⓒ 2017 DGIST
Table Of Contents
1. INTRODUCTION 10-- 1.1 Chronic Total Occlusion (CTO) 10-- 1.2 Conventional surgery for treatment of blood vessel diseas-es 12-- 1.3 Micro-/nano-robots for biomedical applica-tion 15-- 1.4 Soft Material for flexible micro-robots 19-- 1.5 Related research for remotely actuated guidewire (GW) and cathe-ter 22-- 1.5.1 Exterior control system for intravascular treat-ment 22-- 1.5.2 Interior control system for intravascular treat-ment 24-- 2. DESIGN AND MECHANISM 29-- 2.1 Medical microrobots based on guidewire (GW) 29-- 2.2 Mechanism of flexible microrobots 30-- 2.3 Design points of flexible microrobots based on guidewire (GW) 32-- 3. FABRICATION 33-- 3.1 Fabrication of Metal and PDMS mold for replica molding meth-od 33-- 3.1.1 Wire-cutting manufactured metal mold 33-- 3.1.2 Fabrication of PDMS mold using hydrophilic coating and surface treat-ment 34-- 3.2 Fabrication of flexible microrobot 36-- 4. EXPERIMENTS 38-- 4.1 Multiphysics modeling of flexible microrobots for FEM analy-sis 38-- 4.1.1 Geometry and material property of multiphysics model-ing 39-- 4.1.2 Boundary conditions (B.C) of multiphysics model-ing 40-- 4.1.3 Parameter for analysis of multiphysics model-ing 41-- 4.2 Experimental environ-ments 42-- 4.2.1 Magnetic field genera-tor 42-- 4.2.2 Steering experiment of flexible microrobots under external magnetic field 43-- 4.2.3 In vitro experiments in branch and vascular networks mod-el 45-- 5. RESULTS 48-- 5.1 FEM result of flexible microrobots using multi-physics model-ing 48-- 5.2 Steering function of magnetically actuated flexible micro-robots 52-- 5.2.1 Three dimensional (3D) movement of flexible micro-robot 52-- 5.2.2 Characterization of flexible micro-robot 54-- 5.3 Track-ability of flexible micro-robots 56-- 5.3.1 Tracking function of flexible microrobots in single branch phan-tom 56-- 5.3.2 Tracking function of flexible microrobots in blood vessel network phan-tom 59-- 5.4 A robotic assisted percutaneous coronary intervention procedure 61-- 5.4.1 Integrated system for robotic assisted PCI proce-dure 61-- 5.4.2 In vitro experiment with flexible microrobot and integrated sys-tem 62-- 6. DISCUS-SIONS 63-- 7. CONCLUSIONS 65-- 7.1 Conclu-sion 65-- 7.2 Future work 66-- 7.2.1 Beating environment in vitro mode 66
URI
http://dgist.dcollection.net/jsp/common/DcLoOrgPer.jsp?sItemId=000002322452
http://hdl.handle.net/20.500.11750/1514
DOI
10.22677/thesis.2322452
Degree
Master
Department
Robotics Engineering
University
DGIST
Files:
Collection:
Robotics EngineeringThesesMaster


qrcode mendeley

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE